302 results on '"Todd A. Mackenzie"'
Search Results
2. Association between fat‐infiltrated axillary lymph nodes on screening mammography and cardiometabolic disease
- Author
-
Qingyuan Song, Roberta M. diFlorio‐Alexander, Sohum D. Patel, Ryan T. Sieberg, Michael J. Margron, Saif M. Ansari, Margaret R. Karagas, Todd A. Mackenzie, and Saeed Hassanpour
- Subjects
cardiometabolic disease ,ectopic fat ,lymph node ,screening mammography ,Internal medicine ,RC31-1245 - Abstract
Abstract Objective Ectopic fat deposition within and around organs is a stronger predictor of cardiometabolic disease status than body mass index (BMI). Fat deposition within the lymphatic system is poorly understood. This study examined the association between the prevalence of cardiometabolic disease and ectopic fat deposition within axillary lymph nodes (LNs) visualized on screening mammograms. Methods A cross‐sectional study was conducted on 834 women presenting for full‐field digital screening mammography. The status of fat‐infiltrated LNs was assessed based on the size and morphology of axillary LNs from screening mammograms. The prevalence of cardiometabolic disease was retrieved from the electronic medical records, including type 2 diabetes mellitus (T2DM), hypertension, dyslipidemia, high blood glucose, cardiovascular disease, stroke, and non‐alcoholic fatty liver disease. Results Fat‐infiltrated axillary LNs were associated with a high prevalence of T2DM among all women (adjusted odds ratio: 3.92, 95% CI: [2.40, 6.60], p‐value < 0.001) and in subgroups of women with and without obesity. Utilizing the status of fatty LNs improved the classification of T2DM status in addition to age and BMI (1.4% improvement in the area under the receiver operating characteristic curve). Conclusion Fat‐infiltrated axillary LNs visualized on screening mammograms were associated with the prevalence of T2DM. If further validated, fat‐infiltrated axillary LNs may represent a novel imaging biomarker of T2DM in women undergoing screening mammography.
- Published
- 2022
- Full Text
- View/download PDF
3. Quantifying differences in packaged food and drink purchases among households with diet-related cardiometabolic multi-morbidity: a cross-sectional analysis
- Author
-
Iben M. Ricket, Jeremiah R. Brown, Todd A. MacKenzie, Yu Ma, Dhruv Grewal, Kusum L. Ailawadi, and Jennifer A. Emond
- Subjects
Diet-related cardiometabolic multi-morbidity ,Packaged food, and drinks ,Energy and nutrient-density ,Diet and multi-morbidity ,Public aspects of medicine ,RA1-1270 - Abstract
Abstract Background Diet is important for chronic disease management, with limited research understanding dietary choices among those with multi-morbidity, the state of having 2 or more chronic conditions. The objective of this study was to identify associations between packaged food and drink purchases and diet-related cardiometabolic multi-morbidity (DRCMM). Methods Cross-sectional associations between packaged food and drink purchases and household DRCMM were investigated using a national sample of U.S. households participating in a research marketing study. DRCMM households were defined as household head(s) self-reporting 2 or more diet-related chronic conditions. Separate multivariable logistic regression models were used to model the associations between household DRCMM status and total servings of, and total calories and nutrients from, packaged food and drinks purchased per month, as well as the nutrient density (protein, carbohydrates, and fat per serving) of packaged food and drinks purchased per month, adjusted for household size. Results Among eligible households, 3795 (16.8%) had DRCMM. On average, households with DRCMM versus without purchased 14.8 more servings per capita, per month, from packaged foods and drinks (p
- Published
- 2022
- Full Text
- View/download PDF
4. Can diverse population characteristics be leveraged in a machine learning pipeline to predict resource intensive healthcare utilization among hospital service areas?
- Author
-
Iben M. Ricket, Todd A. MacKenzie, Jennifer A. Emond, Kusum L. Ailawadi, and Jeremiah R. Brown
- Subjects
Public aspects of medicine ,RA1-1270 - Abstract
Abstract Background Super-utilizers represent approximately 5% of the population in the United States (U.S.) and yet they are responsible for over 50% of healthcare expenditures. Using characteristics of hospital service areas (HSAs) to predict utilization of resource intensive healthcare (RIHC) may offer a novel and actionable tool for identifying super-utilizer segments in the population. Consumer expenditures may offer additional value in predicting RIHC beyond typical population characteristics alone. Methods Cross-sectional data from 2017 was extracted from 5 unique sources. The outcome was RIHC and included emergency room (ER) visits, inpatient days, and hospital expenditures, all expressed as log per capita. Candidate predictors from 4 broad groups were used, including demographics, adults and child health characteristics, community characteristics, and consumer expenditures. Candidate predictors were expressed as per capita or per capita percent and were aggregated from zip-codes to HSAs using weighed means. Machine learning approaches (Random Forrest, LASSO) selected important features from nearly 1,000 available candidate predictors and used them to generate 4 distinct models, including non-regularized and LASSO regression, random forest, and gradient boosting. Candidate predictors from the best performing models, for each outcome, were used as independent variables in multiple linear regression models. Relative contribution of variables from each candidate predictor group to regression model fit were calculated. Results The median ER visits per capita was 0.482 [IQR:0.351–0.646], the median inpatient days per capita was 0.395 [IQR:0.214–0.806], and the median hospital expenditures per capita was $2,302 [1$,544.70-$3,469.80]. Using 1,106 variables, the test-set coefficient of determination (R2) from the best performing models ranged between 0.184–0.782. The adjusted R2 values from multiple linear regression models ranged from 0.311–0.8293. Relative contribution of consumer expenditures to model fit ranged from 23.4–33.6%. Discussion Machine learning models predicted RIHC among HSAs using diverse population data, including novel consumer expenditures and provides an innovative tool to predict population-based healthcare utilization and expenditures. Geographic variation in utilization and spending were identified.
- Published
- 2022
- Full Text
- View/download PDF
5. Association between chiropractic care and use of prescription opioids among older medicare beneficiaries with spinal pain: a retrospective observational study
- Author
-
James M. Whedon, Sarah Uptmor, Andrew W. J. Toler, Serena Bezdjian, Todd A. MacKenzie, and Louis A. Kazal
- Subjects
Opioids ,Analgesics ,Chiropractic ,Spinal pain ,Medicare ,Spinal manipulation ,RZ201-275 ,Diseases of the musculoskeletal system ,RC925-935 - Abstract
Abstract Background The burden of spinal pain can be aggravated by the hazards of opioid analgesics, which are still widely prescribed for spinal pain despite evidence-based clinical guidelines that identify non-pharmacological therapies as the preferred first-line approach. Previous studies have found that chiropractic care is associated with decreased use of opioids, but have not focused on older Medicare beneficiaries, a vulnerable population with high rates of co-morbidity and polypharmacy. The purpose of this investigation was to evaluate the association between chiropractic utilization and use of prescription opioids among older adults with spinal pain. Methods We conducted a retrospective observational study in which we examined a nationally representative multi-year sample of Medicare claims data, 2012–2016. The study sample included 55,949 Medicare beneficiaries diagnosed with spinal pain, of whom 9,356 were recipients of chiropractic care and 46,593 were non-recipients. We measured the adjusted risk of filling a prescription for an opioid analgesic for up to 365 days following diagnosis of spinal pain. Using Cox proportional hazards modeling and inverse weighted propensity scoring to account for selection bias, we compared recipients of both primary care and chiropractic to recipients of primary care alone regarding the risk of filling a prescription. Results The adjusted risk of filling an opioid prescription within 365 days of initial visit was 56% lower among recipients of chiropractic care as compared to non-recipients (hazard ratio 0.44; 95% confidence interval 0.40–0.49). Conclusions Among older Medicare beneficiaries with spinal pain, use of chiropractic care is associated with significantly lower risk of filling an opioid prescription.
- Published
- 2022
- Full Text
- View/download PDF
6. Association of Sex With the Use and Outcomes of Carotid Revascularization: A Cohort Study
- Author
-
Niveditta Ramkumar, Bjoern D. Suckow, Shipra S. Arya, Todd A. Mackenzie, Art Sedrakyan, Philip P. Goodney, and Jeremiah R. Brown
- Subjects
carotid artery stenting ,carotid endarterectomy ,carotid stenosis ,disparities ,health services research ,sex ,Neurology. Diseases of the nervous system ,RC346-429 ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Background Stroke is a leading cause of death that disproportionately affects women. Treating carotid stenosis with carotid artery stenting (CAS) or carotid endarterectomy (CEA) can prevent ischemic stroke. Yet, the sex‐specific use and long‐term outcomes of these interventions remain unclear. Thus, we sought to investigate sex‐based differences in the treatment and outcomes of carotid stenosis. Methods We analyzed carotid revascularizations in the Vascular Quality Initiative, a national clinical registry. Patients were linked to Medicare claims to identify long‐term outcomes. Our study cohort included patients undergoing index CAS or CEA between 2005 and 2015 who were fee‐for‐service Medicare beneficiaries aged 65+. The primary exposure was sex, and the primary outcome was stroke. Using log‐binomial regression, we estimated the relative risk for CAS treatment accounting for clustering by center. Cox proportional hazards regression was used to estimate the hazard ratio for stroke. We used inverse probability‐weighted risk adjustment based on patient demographics, comorbidities, and disease severity for all analyses. Results In our cohort of 22 341 eligible patients, 39% were women, 13% underwent CAS, and the median survival time was 2.6 years (interquartile range: 1.0–3.4 years). After risk adjustment, women were less likely to undergo CAS than men (adjusted relative risk, 0.89; [95% CI, 0.83–0.96]; P=0.003). Women undergoing carotid revascularization had a 24% increased risk of stroke (adjusted HR, 1.24; [95% CI, 1.10–1.39]; P=0.001) within 5 years of surgery. The higher stroke rate in women was noted following both carotid endarterectomy (adjusted HR, 1.22; [95% CI, 1.07–1.38]; P=0.003) and CAS (adjusted HR, 1.40; [95% CI, 1.06–1.83]; P=0.014). This effect was most pronounced for symptomatic treatment, where women undergoing CEA had a 3% higher risk‐adjusted 5‐year cumulative incidence of stroke (13% versus 10%, Gray's P=0.002). Conclusion Compared with men, women had a higher incidence of postoperative stroke after carotid revascularization, regardless of treatment type. Sex disparities in postrevascularization stroke rates may give rise to concern given the widespread use of revascularization for managing carotid stenosis.
- Published
- 2022
- Full Text
- View/download PDF
7. Time dependent hazard ratio estimation using instrumental variables without conditioning on an omitted covariate
- Author
-
Todd A. MacKenzie, Pablo Martinez-Camblor, and A. James O’Malley
- Subjects
Causal inference ,Censoring ,Semi-parametric model ,Marginal model ,Medicine (General) ,R5-920 - Abstract
Abstract Background Estimation that employs instrumental variables (IV) can reduce or eliminate bias due to confounding. In observational studies, instruments result from natural experiments such as the effect of clinician preference or geographic distance on treatment selection. In randomized studies the randomization indicator is typically a valid instrument, especially if the study is blinded, e.g. no placebo effect. Estimation via instruments is a highly developed field for linear models but the use of instruments in time-to-event analysis is far from established. Various IV-based estimators of the hazard ratio (HR) from Cox’s regression models have been proposed. Methods We extend IV based estimation of Cox’s model beyond proportionality of hazards, and address estimation of a log-linear time dependent hazard ratio and a piecewise constant HR. We estimate the marginal time-dependent hazard ratio unlike other approaches that estimate the hazard ratio conditional on the omitted covariates. We use estimating equations motivated by Martingale representations that resemble the partial likelihood score statistic. We conducted simulations that include the use of copulas to generate potential times-to-event that have a given marginal structural time dependent hazard ratio but are dependent on omitted covariates. We compare our approach to the partial likelihood estimator, and two other IV based approaches. We apply it to estimation of the time dependent hazard ratio for two vascular interventions. Results The method performs well in simulations of a stepwise time-dependent hazard ratio, but illustrates some bias that increases as the hazard ratio moves away from unity (the value that typically underlies the null hypothesis). It compares well to other approaches when the hazard ratio is stepwise constant. It also performs well for estimation of a log-linear hazard ratio where no other instrumental variable approaches exist. Conclusion The estimating equations we propose for estimating a time-dependent hazard ratio using an IV perform well in simulations. We encourage the use of our procedure for time-dependent hazard ratio estimation when unmeasured confounding is a concern and a suitable instrumental variable exists.
- Published
- 2021
- Full Text
- View/download PDF
8. Feasibility and acceptability of a technology-based, rural weight management intervention in older adults with obesity
- Author
-
John A. Batsis, Curtis L. Petersen, Matthew M. Clark, Summer B. Cook, David Kotz, Tyler L. Gooding, Meredith N. Roderka, Rima I. Al-Nimr, Dawna Pidgeon, Ann Haedrich, K. C. Wright, Christina Aquila, and Todd A. Mackenzie
- Subjects
Weight ,Telehealth ,Disparities ,Geriatrics ,RC952-954.6 - Abstract
Abstract Background Older adults with obesity residing in rural areas have reduced access to weight management programs. We determined the feasibility, acceptability and preliminary outcomes of an integrated technology-based health promotion intervention in rural-living, older adults using remote monitoring and synchronous video-based technology. Methods A 6-month, non-randomized, non-blinded, single-arm study was conducted from October 2018 to May 2020 at a community-based aging center of adults aged ≥65 years with a body mass index (BMI) ≥30 kg/m2. Weekly dietitian visits focusing on behavior therapy and caloric restriction and twice-weekly physical therapist-led group strength, flexibility and balance training classes were delivered using video-conferencing to participants in their homes. Participants used a Fitbit Alta HR for remote monitoring with data feedback provided by the interventionists. An aerobic activity prescription was provided and monitored. Results Mean age was 72.9±3.9 years (82% female). Baseline anthropometric measures of weight, BMI, and waist circumference were 97.8±16.3 kg, 36.5±5.2 kg/m2, and 115.5±13.0 cm, respectively. A total of 142 participants were screened (n=27 ineligible), and 53 consented. There were nine dropouts (17%). Overall satisfaction with the trial (4.7+ 0.6, scale: 1 (low) to 5 (high)) and with Fitbit (4.2+ 0.9) were high. Fitbit was worn an average of 81.7±19.3% of intervention days. In completers, mean weight loss was 4.6±3.5 kg or 4.7±3.5% (p
- Published
- 2021
- Full Text
- View/download PDF
9. A new efficient method to detect genetic interactions for lung cancer GWAS
- Author
-
Jennifer Luyapan, Xuemei Ji, Siting Li, Xiangjun Xiao, Dakai Zhu, Eric J. Duell, David C. Christiani, Matthew B. Schabath, Susanne M. Arnold, Shanbeh Zienolddiny, Hans Brunnström, Olle Melander, Mark D. Thornquist, Todd A. MacKenzie, Christopher I. Amos, and Jiang Gui
- Subjects
Genetic interactions ,Machine learning ,Genome-wide association study ,Lung cancer ,Internal medicine ,RC31-1245 ,Genetics ,QH426-470 - Abstract
Abstract Background Genome-wide association studies (GWAS) have proven successful in predicting genetic risk of disease using single-locus models; however, identifying single nucleotide polymorphism (SNP) interactions at the genome-wide scale is limited due to computational and statistical challenges. We addressed the computational burden encountered when detecting SNP interactions for survival analysis, such as age of disease-onset. To confront this problem, we developed a novel algorithm, called the Efficient Survival Multifactor Dimensionality Reduction (ES-MDR) method, which used Martingale Residuals as the outcome parameter to estimate survival outcomes, and implemented the Quantitative Multifactor Dimensionality Reduction method to identify significant interactions associated with age of disease-onset. Methods To demonstrate efficacy, we evaluated this method on two simulation data sets to estimate the type I error rate and power. Simulations showed that ES-MDR identified interactions using less computational workload and allowed for adjustment of covariates. We applied ES-MDR on the OncoArray-TRICL Consortium data with 14,935 cases and 12,787 controls for lung cancer (SNPs = 108,254) to search over all two-way interactions to identify genetic interactions associated with lung cancer age-of-onset. We tested the best model in an independent data set from the OncoArray-TRICL data. Results Our experiment on the OncoArray-TRICL data identified many one-way and two-way models with a single-base deletion in the noncoding region of BRCA1 (HR 1.24, P = 3.15 × 10–15), as the top marker to predict age of lung cancer onset. Conclusions From the results of our extensive simulations and analysis of a large GWAS study, we demonstrated that our method is an efficient algorithm that identified genetic interactions to include in our models to predict survival outcomes.
- Published
- 2020
- Full Text
- View/download PDF
10. Using Satellite Images and Deep Learning to Identify Associations Between County-Level Mortality and Residential Neighborhood Features Proximal to Schools: A Cross-Sectional Study
- Author
-
Joshua J. Levy, Rebecca M. Lebeaux, Anne G. Hoen, Brock C. Christensen, Louis J. Vaickus, and Todd A. MacKenzie
- Subjects
deep learning ,satellite images ,mortality ,remote sensing ,public health ,Public aspects of medicine ,RA1-1270 - Abstract
What is the relationship between mortality and satellite images as elucidated through the use of Convolutional Neural Networks?Background: Following a century of increase, life expectancy in the United States has stagnated and begun to decline in recent decades. Using satellite images and street view images, prior work has demonstrated associations of the built environment with income, education, access to care, and health factors such as obesity. However, assessment of learned image feature relationships with variation in crude mortality rate across the United States has been lacking.Objective: We sought to investigate if county-level mortality rates in the U.S. could be predicted from satellite images.Methods: Satellite images of neighborhoods surrounding schools were extracted with the Google Static Maps application programming interface for 430 counties representing ~68.9% of the US population. A convolutional neural network was trained using crude mortality rates for each county in 2015 to predict mortality. Learned image features were interpreted using Shapley Additive Feature Explanations, clustered, and compared to mortality and its associated covariate predictors.Results: Predicted mortality from satellite images in a held-out test set of counties was strongly correlated to the true crude mortality rate (Pearson r = 0.72). Direct prediction of mortality using a deep learning model across a cross-section of 430 U.S. counties identified key features in the environment (e.g., sidewalks, driveways, and hiking trails) associated with lower mortality. Learned image features were clustered, and we identified 10 clusters that were associated with education, income, geographical region, race, and age.Conclusions: The application of deep learning techniques to remotely-sensed features of the built environment can serve as a useful predictor of mortality in the United States. Although we identified features that were largely associated with demographic information, future modeling approaches that directly identify image features associated with health-related outcomes have the potential to inform targeted public health interventions.
- Published
- 2021
- Full Text
- View/download PDF
11. Association of Magnet Status With Hospitalization Outcomes for Ischemic Stroke Patients
- Author
-
Kimon Bekelis, Symeon Missios, and Todd A. MacKenzie
- Subjects
center of excellence ,ischemic stroke ,magnet recognition ,public reporting ,SPARCS ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
BackgroundIt is not clear whether Magnet recognition by the American Nurses Credentialing Center (nursing excellence program) is associated with improved patient outcomes. We investigated whether hospitalization in a Magnet hospital is associated with improved outcomes for patients with ischemic stroke. Methods and ResultsWe performed a cohort study of patients with ischemic stroke from 2009 to 2013, who were registered in the New York Statewide Planning and Research Cooperative System database. Propensity‐score‐adjusted multivariable regression models were used to adjust for known confounders, with mixed effects methods to control for clustering at the facility level. An instrumental variable analysis was used to control for unmeasured confounding and simulate the effect of a randomized trial. During the study period, 176 557 patients were admitted for ischemic stroke, and met the inclusion criteria. Of these, 32 092 (18.2%) were hospitalized in Magnet hospitals, and 144 465 (81.8%) in non‐Magnet institutions. Instrumental variable analysis demonstrated that hospitalization in Magnet hospitals was associated with lower case‐fatality (adjusted difference, −23.9%; 95% CI, −29.0% to −18.7%), length of stay (adjusted difference, −0.4; 95% CI, −0.8 to −0.1), and rate of discharge to a facility (adjusted difference, −16.5%; 95% CI, −20.0% to −13.0%) in comparison to non‐Magnet hospitals. The same associations were present in propensity‐score‐adjusted mixed effects models. ConclusionsUsing a comprehensive all‐payer cohort of patients with ischemic stroke in New York State, we identified an association of treatment in Magnet hospitals with lower case‐fatality, discharge to a facility, and length of stay. Further research into the factors contributing to the superiority of Magnet hospitals in stroke care is warranted.
- Published
- 2017
- Full Text
- View/download PDF
12. Consistency of Hemoglobin A1c Testing and Cardiovascular Outcomes in Medicare Patients With Diabetes
- Author
-
Philip P. Goodney, Karina A. Newhall, Kimon Bekelis, Daniel Gottlieb, Richard Comi, Sushela Chaudrain, Adrienne E. Faerber, Todd A. Mackenzie, and Jonathan S. Skinner
- Subjects
cardiovascular outcomes ,diabetes mellitus ,health disparities ,health outcomes ,hemoglobin A1c ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
BackgroundAnnual hemoglobin A1c testing is recommended for patients with diabetes mellitus. However, it is unknown how consistently patients with diabetes mellitus receive hemoglobin A1c testing over time, or whether testing consistency is associated with adverse cardiovascular outcomes. Methods and ResultsWe identified 1 574 415 Medicare patients (2002–2012) with diabetes mellitus over the age of 65. We followed each patient for a minimum of 3 years to determine their consistency in hemoglobin A1C testing, using 3 categories: low (testing in 0 or 1 of 3 years), medium (testing in 2 of 3 years), and high (testing in all 3 years). In unweighted and inverse propensity‐weighted cohorts, we examined associations between testing consistency and major adverse cardiovascular events, defined as death, myocardial infarction, stroke, amputation, or the need for leg revascularization. Overall, 70.2% of patients received high‐consistency testing, 17.6% of patients received medium‐consistency testing, and 12.2% of patients received low‐consistency testing. When compared to high‐consistency testing, low‐consistency testing was associated with a higher risk of adverse cardiovascular events or death in unweighted analyses (hazard ratio [HR]=1.21; 95% CI, 1.20–1.23; P
- Published
- 2016
- Full Text
- View/download PDF
13. Acute Kidney Injury Risk Prediction in Patients Undergoing Coronary Angiography in a National Veterans Health Administration Cohort With External Validation
- Author
-
Jeremiah R. Brown, Todd A. MacKenzie, Thomas M. Maddox, James Fly, Thomas T. Tsai, Mary E. Plomondon, Christopher D. Nielson, Edward D. Siew, Frederic S. Resnic, Clifton R. Baker, John S. Rumsfeld, and Michael E. Matheny
- Subjects
angiography ,angioplasty ,catheterization ,contrast media ,kidney ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Background Acute kidney injury (AKI) occurs frequently after cardiac catheterization and percutaneous coronary intervention. Although a clinical risk model exists for percutaneous coronary intervention, no models exist for both procedures, nor do existing models account for risk factors prior to the index admission. We aimed to develop such a model for use in prospective automated surveillance programs in the Veterans Health Administration. Methods and Results We collected data on all patients undergoing cardiac catheterization or percutaneous coronary intervention in the Veterans Health Administration from January 01, 2009 to September 30, 2013, excluding patients with chronic dialysis, end‐stage renal disease, renal transplant, and missing pre‐ and postprocedural creatinine measurement. We used 4 AKI definitions in model development and included risk factors from up to 1 year prior to the procedure and at presentation. We developed our prediction models for postprocedural AKI using the least absolute shrinkage and selection operator (LASSO) and internally validated using bootstrapping. We developed models using 115 633 angiogram procedures and externally validated using 27 905 procedures from a New England cohort. Models had cross‐validated C‐statistics of 0.74 (95% CI: 0.74–0.75) for AKI, 0.83 (95% CI: 0.82–0.84) for AKIN2, 0.74 (95% CI: 0.74–0.75) for contrast‐induced nephropathy, and 0.89 (95% CI: 0.87–0.90) for dialysis. Conclusions We developed a robust, externally validated clinical prediction model for AKI following cardiac catheterization or percutaneous coronary intervention to automatically identify high‐risk patients before and immediately after a procedure in the Veterans Health Administration. Work is ongoing to incorporate these models into routine clinical practice.
- Published
- 2015
- Full Text
- View/download PDF
14. Application of machine learning on colonoscopy screening records for predicting colorectal polyp recurrence.
- Author
-
Lia Harrington, Arief A. Suriawinata, Todd A. MacKenzie, and Saeed Hassanpour
- Published
- 2018
- Full Text
- View/download PDF
15. Association between sex and long‐term outcomes of endovascular treatment for peripheral artery disease
- Author
-
Niveditta Ramkumar, Bjoern D. Suckow, Christian‐Alexander Behrendt, Todd A. Mackenzie, Art Sedrakyan, Jeremiah R. Brown, and Philip P. Goodney
- Subjects
Radiology, Nuclear Medicine and imaging ,General Medicine ,Cardiology and Cardiovascular Medicine - Published
- 2023
16. An Efficient Survival Multifactor Dimensionality Reduction Method for Detecting Gene-Gene Interactions of Lung Cancer Onset Age.
- Author
-
Jennifer Luyapan, Xuemei Ji, Dakai Zhu 0003, Todd A. MacKenzie, Christopher I. Amos, and Jiang Gui
- Published
- 2018
- Full Text
- View/download PDF
17. <scp>Sarcopenia Definition</scp> Outcome Consortium – defined Weakness and Risk of Falls: The National Health and Aging Trends Survey
- Author
-
John A. Batsis, Christian Haudenschild, Rebecca S. Crow, Meredith Gilliam, and Todd A. Mackenzie
- Subjects
General Medicine - Published
- 2023
18. Natural Language Processing for Extracting Colorectal Polyp Information from Electronic Medical Records.
- Author
-
Lia Harrington, Arief A. Suriawinata, Todd A. MacKenzie, John H. Higgins, and Saeed Hassanpour
- Published
- 2018
19. CCR Translation for This Article from MicroRNA-10b Expression Correlates with Response to Neoadjuvant Therapy and Survival in Pancreatic Ductal Adenocarcinoma
- Author
-
Murray Korc, Lorenzo F. Sempere, Edward J. Gutmann, Daniel S. Longnecker, Erin E. Klein, Todd A. Mackenzie, J. Marc Pipas, Stuart R. Gordon, Timothy B. Gardner, and Meir Preis
- Abstract
CCR Translation for This Article from MicroRNA-10b Expression Correlates with Response to Neoadjuvant Therapy and Survival in Pancreatic Ductal Adenocarcinoma
- Published
- 2023
20. Association between fat‐infiltrated axillary lymph nodes on screening mammography and cardiometabolic disease
- Author
-
Roberta M. diFlorio-Alexander, Qingyuan Song, Ryan T Sieberg, Sohum D Patel, Saeed Hassanpour, Saif M Ansari, Todd A. MacKenzie, Michael J Margron, and Margaret R. Karagas
- Subjects
medicine.medical_specialty ,Nutrition and Dietetics ,Receiver operating characteristic ,Axillary lymph nodes ,business.industry ,Medical record ,Endocrinology, Diabetes and Metabolism ,Fatty liver ,Odds ratio ,Disease ,medicine.disease ,medicine.anatomical_structure ,Internal medicine ,medicine ,business ,Stroke ,Dyslipidemia - Abstract
ObjectiveEctopic fat deposition within and around organs is a stronger predictor of cardiometabolic disease status than body mass index. Fat deposition within the lymphatic system is poorly understood. This study examined the association between the prevalence of cardiometabolic disease and ectopic fat deposition within axillary lymph nodes (LNs) visualized on screening mammograms.MethodsA cross-sectional study was conducted on 834 women presenting for full-field digital screening mammography. The status of fat-infiltrated LNs was assessed based on the size and morphology of axillary LNs from screening mammograms. The prevalence of cardiometabolic disease was retrieved from the electronic medical records, including type 2 diabetes mellitus (T2DM), hypertension, dyslipidemia, high blood glucose, cardiovascular disease, stroke, and non-alcoholic fatty liver disease.ResultsFat-infiltrated axillary LNs were associated with a high prevalence of T2DM among all women (adjusted odds ratio: 3.92, 95% CI: [2.40, 6.60], p-value < 0.001) and in subgroups of women with and without obesity. Utilizing the status of fatty LNs improved the classification of T2DM status in addition to age and BMI (1.4% improvement in the area under the receiver operating characteristic curve).ConclusionFat-infiltrated axillary LNs visualized on screening mammograms were associated with the prevalence of T2DM. If further validated, fat-infiltrated axillary LNs may represent a novel imaging biomarker of T2DM in women undergoing screening mammography.
- Published
- 2022
21. Mendelian randomization in the multivariate general linear model framework
- Author
-
Ethan M. Lange, Dustin M. Long, Todd A. MacKenzie, Inmaculada Aban, Marguerite R. Irvin, Phillip H. Allman, Gary Cutter, Hemant K. Tiwari, Amit Patki, and Leslie A. Lange
- Subjects
General linear model ,Multivariate statistics ,Models, Genetic ,Epidemiology ,Smoking ,Instrumental variable ,Mendelian Randomization Analysis ,Causality ,Exponential family ,Null (SQL) ,Statistics ,Mendelian randomization ,Linear Models ,Range (statistics) ,Humans ,Genetics (clinical) ,Mathematics ,Statistical hypothesis testing - Abstract
Mendelian randomization (MR) is an application of instrumental variable (IV) methods to observational data in which the IV is a genetic variant. MR methods applicable to the general exponential family of distributions are currently not well characterized. We adapt a general linear model framework to the IV setting and propose a general MR method applicable to any full-rank distribution from the exponential family. Empirical bias and coverage are estimated via simulations. The proposed method is compared to several existing MR methods. Real data analyses are performed using data from the REGARDS study to estimate the potential causal effect of smoking frequency on stroke risk in African Americans. In simulations with binary variates and very weak instruments the proposed method had the lowest median [Q1 , Q3 ] bias (0.10 [-3.68 to 3.62]); compared with 2SPS (0.27 [-3.74 to 4.26]) and the Wald method (-0.69 [-1.72 to 0.35]). Low bias was observed throughout other simulation scenarios; as well as more than 90% coverage for the proposed method. In simulations with count variates, the proposed method performed comparably to 2SPS; the Wald method maintained the most consistent low bias; and 2SRI was biased towards the null. Real data analyses find no evidence for a causal effect of smoking frequency on stroke risk. The proposed MR method has low bias and acceptable coverage across a wide range of distributional scenarios and instrument strengths; and provides a more parsimonious framework for asymptotic hypothesis testing compared to existing two-stage procedures.
- Published
- 2021
22. Clinically significant serrated polyp detection rates and risk for postcolonoscopy colorectal cancer: data from the New Hampshire Colonoscopy Registry
- Author
-
Joseph C, Anderson, William, Hisey, Todd A, Mackenzie, Christina M, Robinson, Amitabh, Srivastava, Reinier G S, Meester, Lynn F, Butterly, and Public Health
- Subjects
Adenoma ,Polyps ,SDG 3 - Good Health and Well-being ,Gastroenterology ,Colonic Polyps ,Humans ,New Hampshire ,Radiology, Nuclear Medicine and imaging ,Colonoscopy ,Registries ,Colorectal Neoplasms - Abstract
Background and Aims: Higher adenoma detection rates reduce the risk of postcolonoscopy colorectal cancer (PCCRC). Clinically significant serrated polyps (CSSPs; defined as any sessile serrated polyp, traditional serrated adenoma, large [≥1 cm] or proximal hyperplastic polyp >5 mm) also lead to PCCRC, but there are no data on associated CSSP detection rates (CSSDRs). We used data from the New Hampshire Colonoscopy Registry (NHCR) to investigate the association between PCCRC risk and endoscopist CSSDR. Methods: We included NHCR patients with 1 or more follow-up events: either a colonoscopy or a colorectal cancer (CRC) diagnosis identified through linkage with the New Hampshire State Cancer Registry. We defined our outcome, PCCRC, in 3 time periods: CRC diagnosed 6 to 36 months, 6 to 60 months, or all examinations (6 months or longer) after an index examination. We excluded patients with CRC diagnosed at or within 6 months of the index examination, with incomplete examinations, or with inflammatory bowel disease. The exposure variable was endoscopist CSSDR at the index colonoscopy. Cox regression was used to model the hazard of PCCRC on CSSDR controlling for age, sex, index findings, year of examination, personal history of colorectal neoplasia, and having more than 1 surveillance examination. Results: One hundred twenty-eight patients with CRC diagnosed at least 6 months after their index examination were included. Our cohort included 142 endoscopists (92 gastroenterologists). We observed that the risk for PCCRC 6 months or longer after the index examination was significantly lower for examinations performed by endoscopists with CSSDRs of 3% to
- Published
- 2022
23. Association between cervical artery dissection and spinal manipulative therapy -a medicare claims analysis
- Author
-
James M Whedon, Curtis L Petersen, Zhongze Li, William J Schoelkopf, Scott Haldeman, Todd A MacKenzie, and Jon D Lurie
- Subjects
Manipulation, Spinal ,Vertebral Artery Dissection ,Carotid Artery Diseases ,Insurance Claim Review ,Humans ,Arteries ,Geriatrics and Gerontology ,Medicare ,United States ,Aged ,Ischemic Stroke - Abstract
Background Cervical artery dissection and subsequent ischemic stroke is the most serious safety concern associated with cervical spinal manipulation. Methods We evaluated the association between cervical spinal manipulation and cervical artery dissection among older Medicare beneficiaries in the United States. We employed case-control and case-crossover designs in the analysis of claims data for individuals aged 65+, continuously enrolled in Medicare Part A (covering hospitalizations) and Part B (covering outpatient encounters) for at least two consecutive years during 2007–2015. The primary exposure was cervical spinal manipulation; the secondary exposure was a clinical encounter for evaluation and management for neck pain or headache. We created a 3-level categorical variable, (1) any cervical spinal manipulation, 2) evaluation and management but no cervical spinal manipulation and (3) neither cervical spinal manipulation nor evaluation and management. The primary outcomes were occurrence of cervical artery dissection, either (1) vertebral artery dissection or (2) carotid artery dissection. The cases had a new primary diagnosis on at least one inpatient hospital claim or primary/secondary diagnosis for outpatient claims on at least two separate days. Cases were compared to 3 different control groups: (1) matched population controls having at least one claim in the same year as the case; (2) ischemic stroke controls without cervical artery dissection; and (3) case-crossover analysis comparing cases to themselves in the time period 6–7 months prior to their cervical artery dissection. We made each comparison across three different time frames: up to (1) 7 days; (2) 14 days; and (3) 30 days prior to index event. Results The odds of cervical spinal manipulation versus evaluation and management did not significantly differ between vertebral artery dissection cases and any of the control groups at any of the timepoints (ORs 0.84 to 1.88; p > 0.05). Results for carotid artery dissection cases were similar. Conclusion Among Medicare beneficiaries aged 65 and older who received cervical spinal manipulation, the risk of cervical artery dissection is no greater than that among control groups.
- Published
- 2022
24. Abstract 245: Increased Prevalence Of Children With Congenital Heart Disease In Colorado From 2012 - 2019
- Author
-
Devin M Parker, Jeremiah R Brown, Meagan E Stabler, Allen D Everett, and Todd A MacKenzie
- Subjects
Cardiology and Cardiovascular Medicine - Abstract
Introduction: Congenital heart defects (CHD) are the most common birth defects and are estimated to affect almost 1% of births per year in the US. Most CHD prevalence estimates are based on data from population-based birth defects surveillance systems and these estimates are inconsistent due to varied definitions. It is therefore important to derive high-quality, population-based estimates of the prevalence of CHD to help care for this vulnerable population. Methods: We analyzed all payer claims data (APCD) from Colorado from 2012-2019. Children with CHD were identified by applying CHD ICD-9 and ICD-10 diagnoses codes from the Society of Thoracic Surgeons (STS) International Society for Nomenclature of Paediatric and Congenital Heart Disease (ISNPCHD) harmonized cardiac codes. We included children with CHD < 18 years of age who resided in Colorado, had a documented zip code, and had at least one ambulatory healthcare claim. We analyzed the test for linear trends in the proportion of CHD diagnoses from 2012-2019 with the Cochran-Armitage (Z) test. Differences among patient characteristics and CHD diagnosis were tested using the Pearson Chi-square test and Wilcoxon rank sum tests as appropriate. Results: Overall the current study analyzed 1,565,438 children with 36,567 CHD diagnoses (i.e. 23.4 per 1,000 live births), comprising 2.3% of the pediatric population. Between 2012 and 2019 the statewide rate of children diagnosed with CHD significantly increased from 21.9 to 32.3 per 1,000 children per year (Z: 5.38; p Conclusion: The current study is the first population-level analysis of pediatric CHD in the US and these findings suggest that the statewide CHD prevalence rate has increased significantly since 2012. Children with CHD are a priority population for quality improvement in pediatrics given their growing prevalence and corresponding risk of adverse outcomes.
- Published
- 2022
25. Discussion on 'Instrumental variable estimation of the causal hazard ratio' by Linbo Wang, Eric Tchetgen Tchetgen, Torben Martinussen, and Stijn Vansteelandt
- Author
-
A. James O'Malley, Pablo Martínez‐Camblor, and Todd A. MacKenzie
- Subjects
Statistics and Probability ,General Immunology and Microbiology ,Applied Mathematics ,General Medicine ,General Agricultural and Biological Sciences ,General Biochemistry, Genetics and Molecular Biology - Published
- 2022
26. DAR-901 vaccine for the prevention of infection with Mycobacterium tuberculosis among BCG-immunized adolescents in Tanzania: A randomized controlled, double-blind phase 2b trial
- Author
-
Wendy Wieland-Alter, Robert D. Arbeit, Isaac Maro, Lisa V. Adams, Albert Magohe, Chris Bailey-Kellogg, Jamila Said, Susan Tvaroha, Christiaan A. Rees, Keiko Nakamura, Patricia Munseri, Mecky Matee, Todd A. MacKenzie, Maryam Amour, C. Robert Horsburgh, Kisali Pallangyo, and C. Fordham von Reyn
- Subjects
medicine.medical_specialty ,Tuberculosis ,Adolescent ,030231 tropical medicine ,Interferon gamma release assay ,Disease ,Placebo ,Tanzania ,Mycobacterium tuberculosis ,03 medical and health sciences ,0302 clinical medicine ,Immune system ,Internal medicine ,parasitic diseases ,medicine ,Humans ,030212 general & internal medicine ,Abscess ,General Veterinary ,General Immunology and Microbiology ,biology ,Tuberculin Test ,business.industry ,Public Health, Environmental and Occupational Health ,biology.organism_classification ,medicine.disease ,Infectious Diseases ,Cohort ,BCG Vaccine ,Molecular Medicine ,business ,Interferon-gamma Release Tests - Abstract
Background SRL172 prevented disease due to Mycobacterium tuberculosis in a Phase 3 trial. DAR-901 represents a scalable manufacturing process for SRL172. We sought to determine if DAR-901 would prevent infection with M. tuberculosis among BCG-primed adolescents age 13–15 years in Tanzania. Methods Adolescents with a negative T- SPOT.TBR interferon gamma release assay (IGRA) were randomized 1:1 to three intradermal injections of DAR-901 or saline placebo at 0, 2 and 4 months. Repeat IGRAs were performed at 2 months, and at 1, 2, and 3 years. The primary efficacy outcome was time to new TB infection (IGRA conversion to positive); the secondary outcome was time to persistent TB infection (IGRA conversion with repeat positive IGRA). Results Among 936 participants screened 667 were eligible and randomized to their first dose of vaccine or placebo (safety cohort). At 2 months, 625 participants remained IGRA-negative and were scheduled for the additional two doses (efficacy cohort). DAR-901 was safe and well-tolerated. One DAR-901 recipient developed a vaccine site abscess. Neither the primary nor secondary endpoints differed between the two treatment arms (p = 0.90 and p = 0.20, respectively). DAR-901 IGRA converters had median responses to ESAT-6 of 50.1 spot-forming cells (SFCs) vs. 19.6 SFCs in placebo IGRA converters (p = 0.03). Conclusions A three-dose series of 1 mg DAR-901 was safe and well-tolerated but did not prevent initial or persistent IGRA conversion. DAR-901 recipients with IGRA conversion demonstrated enhanced immune responses to ESAT-6. Since protection against disease may require different immunologic responses than protection against infection a trial of DAR-901 to prevent TB disease is warranted. Trial Registration. The trial is registered at ClinicalTrials.gov as NCT02712424.
- Published
- 2020
27. Novel integration of governmental data sources using machine learning to identify super-utilization among U.S. counties
- Author
-
Iben M. Ricket, Michael E. Matheny, Todd A. MacKenzie, Jennifer A. Emond, Kusum L. Ailawadi, and Jeremiah R. Brown
- Subjects
Artificial Intelligence ,Medicine (miscellaneous) ,Health Informatics ,Computer Science Applications - Published
- 2023
28. Cardiac Biomarkers Predict Long-term Survival After Cardiac Surgery
- Author
-
Devin M. Parker, Jeremiah R. Brown, David J. Malenka, Jeffrey P. Jacobs, Niveditta Ramkumar, Todd A. MacKenzie, Richard B. Berman, Donald S. Likosky, and Anthony W. DiScipio
- Subjects
Male ,Pulmonary and Respiratory Medicine ,medicine.medical_specialty ,030204 cardiovascular system & hematology ,Article ,03 medical and health sciences ,0302 clinical medicine ,Interquartile range ,Internal medicine ,Natriuretic Peptide, Brain ,medicine ,Humans ,Hospital Mortality ,Postoperative Period ,Prospective Studies ,Cardiac Surgical Procedures ,Protein Precursors ,Prospective cohort study ,Survival rate ,Survival analysis ,Aged ,business.industry ,Proportional hazards model ,Receptors, Interleukin-1 ,Middle Aged ,Interleukin-1 Receptor-Like 1 Protein ,Peptide Fragments ,United States ,Cardiac surgery ,Survival Rate ,030228 respiratory system ,Cohort ,Biomarker (medicine) ,Female ,Surgery ,Cardiology and Cardiovascular Medicine ,business ,Biomarkers ,Follow-Up Studies ,Forecasting - Abstract
Cardiac biomarkers soluble ST-2 (sST-2) and N-terminal prohormone B-type natriuretic peptide (NT-proBNP) may be associated with long-term survival after cardiac surgery. This study explored the relationship between long-term survival after cardiac surgery and serum biomarker levels.Patients undergoing cardiac surgery from 2004 to 2007 were enrolled in a prospective biomarker cohort in the Northern New England Cardiovascular Disease Study Group Registry. Preoperative serum biomarker levels, postoperative serum biomarker levels, and the change in serum biomarker levels were categorized by quartile. The study used Kaplan-Meier survival analysis and Cox regression models adjusted for variables in the American College of Cardiology Foundation-Society of Thoracic Surgeons Collaboration on the Comparative Effectiveness of Revascularization Strategy (ASCERT) long-term survival calculator to study the association of biomarker levels with long-term survival. After Kaplan-Meier analysis, quartiles 2 and 3 were found to have similar survival and were therefore combined into 1 category.In the study cohort (n = 1648), median follow-up time was 8.5 years (interquartile range, 7.6-9.7 years), during which there were 227 deaths. The 10-year survival rate was 86%. Kaplan-Meier survival analysis demonstrated a significant (P.001) difference across quartiles of each biomarker level measurement. After adjustment, preoperative levels, postoperative levels, and the change in biomarker levels in quartile 4 (highest serum levels or change) were significantly predictive of worse survival (hazard ratio range, 1.77-2.89; all P.05) compared with quartile 1; however, levels of sST-2 and NT-proBNP in quartiles 2 and 3 demonstrated a nonstatistically significant trend with long-term survival.Elevated preoperative and postoperative levels of sST-2 or NT-proBNP and large changes in these biomarkers' levels are associated with an increased risk of worse survival after cardiac surgery. These biomarkers can be used for risk stratification or assessing postsurgical prognosis.
- Published
- 2019
29. Clip Closure Does Not Reduce Risk of Bleeding After Resection of Large Serrated Polyps: Results From a Randomized Trial
- Author
-
Seth D. Crockett, Mouen Khashab, Douglas K. Rex, Ian S. Grimm, Matthew T. Moyer, Amit Rastogi, Todd A. Mackenzie, Heiko Pohl, Firas H. Al-Kawas, Fadi Antaki, Harry R. Aslanian, Pooja A. Elias, B. Joseph Elmunzer, Jeffrey A. Gill, Stuart R. Gordon, Muhammad K. Hasan, Mouen A. Khashab, Ryan J. Law, John M. Levenick, Abraham Mathew, Oswaldo Ortiz, Maria Pellise, Douglas Pleskow, Daniel von Renteln, and Omid Sanaei
- Subjects
Adenoma ,Adenomatous Polyps ,Hepatology ,Endoscopic Mucosal Resection ,Gastroenterology ,Colonic Polyps ,Humans ,Colonoscopy ,Postoperative Hemorrhage ,Colorectal Neoplasms - Abstract
Serrated polyps are important colorectal cancer precursors and are most commonly located in the proximal colon, where post-polypectomy bleeding rates are higher. There is limited clinical trial evidence to guide best practices for resection of large serrated polyps (LSPs).In a multicenter trial, patients with large (≥20 mm) non-pedunculated polyps undergoing endoscopic mucosal resection (EMR) were randomized to clipping of the resection base or no clipping. This analysis is stratified by histologic subtype of study polyp(s), categorized as serrated [sessile serrated lesions (SSLs) or hyperplastic polyps (HPs)] or adenomatous, comparing clip vs control groups. The primary outcome was severe post-procedure bleeding within 30 days of colonoscopy.A total of 179 participants with 199 LSPs (191 SSLs and 8 HPs) and 730 participants with 771 adenomatous polyps were included in the study. Overall, 5 patients with LSPs (2.8%) experienced post-procedure bleeding compared with 42 (5.8%) of those with adenomas. There was no difference in post-procedure bleeding rates between patients in the clip vs control group among those with LSPs (2.3% vs 3.3%, respectively, difference 1.0%; P = NS). However, among those with adenomatous polyps, clipping was associated with a lower risk of post-procedure bleeding (3.9% vs 7.6%, difference 3.7%; P = .03) and overall serious adverse events (5.5% vs 10.6%, difference 5.1%; P = .01).The post-procedure bleeding risk for LSPs removed via EMR is low, and there is no discernable benefit of prophylactic clipping of the resection base in this group. This study indicates that the benefit of endoscopic clipping following EMR may be specific for2 cm adenomatous polyps located in the proximal colon.gov, Number: NCT01936948.
- Published
- 2021
30. Improvement of sepsis identification through multi-year comparison of sepsis and early warning scores
- Author
-
Irina Perreard, Michael S. Calderwood, Susan P. McGrath, and Todd A. MacKenzie
- Subjects
Male ,medicine.medical_specialty ,Organ Dysfunction Scores ,Risk Assessment ,Sensitivity and Specificity ,Sepsis ,Trauma Centers ,False positive paradox ,medicine ,Humans ,Single institution ,Cause of death ,Aged ,Retrospective Studies ,Warning system ,business.industry ,Sequential organ failure assessment ,Reproducibility of Results ,General Medicine ,Middle Aged ,medicine.disease ,Sepsis group ,ROC Curve ,Early Warning Score ,Case-Control Studies ,Emergency medicine ,Emergency Medicine ,Female ,business ,General deterioration - Abstract
Background Sepsis remains a leading cause of death among inpatients. Scoring systems designed to identify inpatients with sepsis currently have limited effectiveness. This single institution, retrospective, case-control study aims to improve sepsis decision support tool performance using temporal analyses of sepsis-specific and general deterioration scoring systems. Methods Sequential Organ Failure Assessment, National Early Warning Scores (NEWS), and Modified Early Warning Scores were calculated using four years of inpatient data. Sensitivity and specificity analyses compared performance of each score, calculated as a function of both various score cut-off values and time before sepsis diagnosis using established proxies for identifying clinical suspicion for sepsis. Results NEWS had the best sensitivity-specificity performance (AUROC 82.7) when examining various score cutoffs and time intervals during which diagnosis criteria were met. Comparison of false positives/negatives with various score thresholds showed a low rate of false positives with a NEWS of 7. Score trends in the hours leading up to sepsis criteria being met showed a marked increase for the sepsis group while for the cases there was a decrease during a comparable period. Conclusions Temporal analyses of scores for patients coded as having sepsis provides novel insights into patterns of deterioration. The methods and results provide practical details demonstrating how general deterioration algorithms can be used to alert trained responders to potential cases of sepsis to improve sepsis recognition and treatment opportunities.
- Published
- 2021
31. The practice of cranial neurosurgery and the malpractice liability environment in the United States.
- Author
-
Kimon Bekelis, Symeon Missios, Kendrew Wong, and Todd A MacKenzie
- Subjects
Medicine ,Science - Abstract
The potential imbalance between malpractice liability cost and quality of care has been an issue of debate. We investigated the association of malpractice liability with unfavorable outcomes and increased hospitalization charges in cranial neurosurgery.We performed a retrospective cohort study involving patients who underwent cranial neurosurgical procedures from 2005-2010, and were registered in the National Inpatient Sample (NIS) database. We used data from the National Practitioner Data Bank (NPDB) from 2005 to 2010 to create measures of volume and size of malpractice claim payments. The association of the latter with the state-level mortality, length of stay (LOS), unfavorable discharge, and hospitalization charges for cranial neurosurgery was investigated.During the study period, there were 189,103 patients (mean age 46.4 years, with 48.3% females) who underwent cranial neurosurgical procedures, and were registered in NIS. In a multivariable regression, higher number of claims per physician in a state was associated with increased ln-transformed hospitalization charges (beta 0.18; 95% CI, 0.17 to 0.19). On the contrary, there was no association with mortality (OR 1.00; 95% CI, 0.94 to 1.06). We observed a small association with unfavorable discharge (OR 1.09; 95% CI, 1.06 to 1.13), and LOS (beta 0.01; 95% CI, 0.002 to 0.03). The size of the awarded claims demonstrated similar relationships. The average claims payment size (ln-transformed) (Pearson's rho=0.435, P=0.01) demonstrated a positive correlation with the risk-adjusted hospitalization charges but did not demonstrate a correlation with mortality, unfavorable discharge, or LOS.In the present national study, aggressive malpractice environment was not correlated with mortality but was associated with higher hospitalization charges after cranial neurosurgery. In view of the association of malpractice with the economics of healthcare, further research on its impact is necessary.
- Published
- 2015
- Full Text
- View/download PDF
32. Surgical Clipping versus Endovascular Intervention for the Treatment of Subarachnoid Hemorrhage Patients in New York State.
- Author
-
Kimon Bekelis, Symeon Missios, Shannon Coy, Redi Rahmani, Robert J Singer, and Todd A MacKenzie
- Subjects
Medicine ,Science - Abstract
Randomized trials have demonstrated a survival benefit for endovascular treatment of ruptured cerebral aneurysms. We investigated the association of surgical clipping and endovascular coiling with outcomes in subarachnoid hemorrhage (SAH) patients in a real-world regional cohort.We performed a cohort study involving patients with ruptured cerebral aneurysms, who underwent surgical clipping, or endovascular coiling from 2009-2013 and were registered in the Statewide Planning and Research Cooperative System (SPARCS) database. An instrumental variable analysis was used to investigate the association of treatment technique with outcomes.Of the 4,098 patients undergoing treatment, 2,585 (63.1%) underwent coiling, and 1,513 (36.9%) underwent clipping. Using an instrumental variable analysis, we did not identify a difference in inpatient mortality [marginal effect (ME), -0.56; 95% CI, -1.03 to 0.02], length of stay (LOS) (ME, 1.72; 95% CI, -3.39 to 6.84), or the rate of 30-day readmissions (ME, -0.30; 95% CI, -0.82 to 0.22) between the two treatment techniques for patients with SAH. Clipping was associated with a higher rate of discharge to rehabilitation (ME, 0.63; 95% CI, 0.24 to 1.01). In sensitivity analysis, mixed effect regression, and propensity score adjusted regression models demonstrated identical results.Using a comprehensive all-payer cohort of patients in New York State presenting with aneurysmal SAH we did not identify an association of treatment method with mortality, LOS or 30-day readmission. Clipping was associated with a higher rate of discharge to rehabilitation.
- Published
- 2015
- Full Text
- View/download PDF
33. Multicenter, Open-Label, Phase II Study of Bendamustine and Rituximab Followed by 90-Yttrium (Y) Ibritumomab Tiuxetan for Untreated Follicular Lymphoma (Fol-BRITe)
- Author
-
Cristiana A Costa, Todd A. MacKenzie, Anne W. Beaven, Sara R Metzler, Bonnie Toaso, Eric S. Winer, Lynn Shaw, Bassem I. Zaki, Helen Ryan, Youdinghuan Chen, Stephanie P. Yen, Frederick Lansigan, and Darcie Findley
- Subjects
Adult ,Male ,0301 basic medicine ,Bendamustine ,Cancer Research ,medicine.medical_specialty ,medicine.medical_treatment ,Ibritumomab tiuxetan ,Follicular lymphoma ,Phases of clinical research ,Gastroenterology ,Drug Administration Schedule ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,Antineoplastic Combined Chemotherapy Protocols ,Bendamustine Hydrochloride ,Humans ,Medicine ,Prospective Studies ,Progression-free survival ,Lymphoma, Follicular ,Aged ,Chemotherapy ,business.industry ,Remission Induction ,Antibodies, Monoclonal ,Chemoradiotherapy ,Middle Aged ,Radioimmunotherapy ,medicine.disease ,Progression-Free Survival ,030104 developmental biology ,Oncology ,Tolerability ,030220 oncology & carcinogenesis ,Female ,Rituximab ,business ,medicine.drug - Abstract
Purpose: Bendamustine and rituximab (BR) has been established as a superior frontline therapy over R-CHOP in the treatment of follicular lymphoma (FL). Yttrium-90 Ibritumomab tiuxetan (90YIT) is an effective consolidation strategy after chemotherapy induction. This prospective, single-arm, multicenter, phase II trial evaluated the response rate, progression-free survival (PFS), and tolerability of BR followed by consolidation with 90YIT in patients with untreated FL. Patients and Methods: The study included grade 1 to 3a FL patients aged ≥18 years, chemotherapy-naïve, and requiring treatment for stage II–IV disease. Study treatment included an initial rituximab treatment, followed by four cycles of BR. Patients were eligible for consolidation with 90YIT, 6 to 12 weeks after BR, if they obtained at least a partial response after induction had adequate count recovery and bone marrow infiltration < 25%. Results: Thirty-nine patients were treated. Eighty-two percent had an intermediate or high-risk Follicular Lymphoma International Prognostic Index score, and 6 of 39 (15%) were grade 3a. The response rate was 94.8%, and the complete response(CR)/CR unconfirmed (CRu) rate was 77% in the intention-to-treat analysis. The conversion rate from PR to CR/Cru after 90YIT was 81%. After median follow-up of 45 months, the PFS was 0.71 (95% confidence interval, 0.57–0.89). Conclusions: This report demonstrates that four cycles of BR followed by consolidation with 90YIT achieve high response rates that are durable. In addition, consolidation with 90YIT results in a high conversion rate of PR to CR/CRu. A short course of BR followed by 90YIT is a safe and effective regimen for frontline treatment of FL.
- Published
- 2019
34. Influence of child-targeted fast food TV advertising exposure on fast food intake: A longitudinal study of preschool-age children
- Author
-
Lauren P. Cleveland, Keith M. Drake, Kristy Hendricks, Jennifer E. Carroll, Todd A. MacKenzie, Jennifer L. Harris, Jennifer A. Emond, Linda J. Titus, Meghan R Longacre, Kelly Gaynor, and Madeline A. Dalton
- Subjects
Adult ,Male ,Parents ,0301 basic medicine ,Longitudinal study ,Restaurants ,Child Behavior ,030209 endocrinology & metabolism ,Diet Surveys ,Article ,Childhood obesity ,Fast food intake ,Eating ,03 medical and health sciences ,symbols.namesake ,0302 clinical medicine ,Advertising ,medicine ,Humans ,New Hampshire ,Longitudinal Studies ,Poisson regression ,General Psychology ,Consumption (economics) ,Preschool child ,030109 nutrition & dietetics ,Nutrition and Dietetics ,Potential risk ,Feeding Behavior ,medicine.disease ,Diet ,Child, Preschool ,symbols ,Fast Foods ,Female ,Television ,Psychology - Abstract
INTRODUCTION: Fast food (FF) advertising is a potential risk factor for FF consumption among children, yet the impact of such advertising on children’s FF intake has not been assessed in a longitudinal, naturalistic study. Whether parents’ FF consumption mitigates advertising effects is also unknown. METHODS: One-year, longitudinal study among 624 preschool-age children, 3–5 years old, and one parent each recruited from New Hampshire, 2014–2015. Parents completed six online surveys every eight weeks and, at each, reported the number of times their children consumed FF in the past week. Each child’s advertisement exposure was determined by counting the brand-specific FF advertisements aired within the programs they viewed on children’s TV networks during the study. At baseline, parents reported the frequency of their own FF consumption. Data were analyzed in 2017–2018. RESULTS: Three FF brands targeted TV advertising to children during the study: McDonald’s, Wendy’s and Subway. Few children were exposed to child-targeted advertising for Wendy’s or Subway. Results from adjusted Poisson regression models focused on McDonald’s showed a differential effect of advertisement exposure on children’s McDonald’s intake in the past week (any or mean intake) by parental FF consumption (P
- Published
- 2019
35. The impact of frequent cystoscopy on surgical care and cancer outcomes among patients with low‐risk, non–muscle‐invasive bladder cancer
- Author
-
Douglas J. Robertson, Philip P. Goodney, Kristine E. Lynch, Todd A. MacKenzie, David S. Han, Brenda E. Sirovich, John D. Seigne, Zhongze Li, and Florian R. Schroeck
- Subjects
Cancer Research ,medicine.medical_specialty ,Bladder cancer ,medicine.diagnostic_test ,business.industry ,Surgical care ,Urology ,Cancer ,Retrospective cohort study ,Cystoscopy ,medicine.disease ,Cystoscopies ,Article ,03 medical and health sciences ,0302 clinical medicine ,Oncology ,030220 oncology & carcinogenesis ,medicine ,030212 general & internal medicine ,business ,Non muscle invasive ,Veterans Affairs - Abstract
BACKGROUND: Surveillance recommendations for patients with low-risk non-muscle-invasive bladder cancer (NMIBC) are based on limited evidence. Our objective was to add to the evidence by assessing outcomes after frequent versus recommended cystoscopic surveillance. METHODS: This is a retrospective cohort study of patients diagnosed with low-risk (low grade Ta) NMIBC from 2005 – 2011 with follow-up through 2014 from the Department of Veterans Affairs. Patients were classified as having undergone frequent versus recommended cystoscopic surveillance (>3 versus 1–3 cystoscopies in the first 2 years after diagnosis). Using propensity score adjusted models, we estimated the impact of frequent cystoscopy on the number of transurethral resections, the number of resections without cancer in the specimen, and on risk of progression to muscle-invasive cancer or bladder cancer death. RESULTS: Among 1,042 patients, 798 (77%) had more frequent cystoscopy than recommended. In adjusted analyses, the frequent cystoscopy group had twice as many transurethral resections (55 versus 26 per 100 person years; p
- Published
- 2019
36. An Instrumental Variable Procedure for Estimating Cox Models with Non-Proportional Hazards in the Presence Of Unmeasured Confounding
- Author
-
Douglas O. Staiger, Todd A. MacKenzie, Pablo Martínez-Camblor, Phillip Goodney, and A. James O'Malley
- Subjects
Statistics and Probability ,Hazard (logic) ,Proportional hazards model ,Computer science ,medicine.medical_treatment ,Instrumental variable ,Estimator ,Context (language use) ,medicine.disease ,Residual ,01 natural sciences ,010104 statistics & probability ,03 medical and health sciences ,0302 clinical medicine ,Carotid artery disease ,medicine ,Econometrics ,030212 general & internal medicine ,0101 mathematics ,Statistics, Probability and Uncertainty ,Endarterectomy - Abstract
Summary Two-stage instrumental variable methods are commonly used for estimating average causal effects in the presence of an unmeasured confounder. In the context of the proportional hazard Cox regression models, this problem has recently received attention with several methods being proposed. Previously, we developed an improved estimator under the incumbent two-stage residual inclusion procedure called ‘2SRI’ by adding a Gaussian frailty in the second stage. We now consider the more complex situation in which the treatment and the unmeasured confounders can have time varying effects, illustrating the method with the case of a step function with one prespecified change point. We prove that, in situations where the effects of the unmeasured confounder or the treatment change during the follow-up, the first stage of the 2SRI algorithm induces a frailty with time varying coefficients in the second stage, which enables incumbent methods and our previously developed procedure to be improved on. A Monte Carlo simulation study demonstrates the superior performance of the proposed extension of 2SRI that we develop. We apply the new procedure to estimate the effect of endarterectomy versus carotid artery stenting on the time to death of patients suffering from carotid artery disease by using linked vascular quality initiative registry–Medicare data.
- Published
- 2019
37. Improving Patient Safety and Clinician Workflow in the General Care Setting With Enhanced Surveillance Monitoring
- Author
-
Susan P. McGrath, Kelli A. Converse, Melissa D. Garland, Todd A. MacKenzie, and Irina Perreard
- Subjects
Quality management ,Remote patient monitoring ,Vital signs ,Health Informatics ,Workflow ,03 medical and health sciences ,Patient safety ,0302 clinical medicine ,Documentation ,Health Information Management ,030202 anesthesiology ,Information system ,Humans ,Medicine ,Oximetry ,030212 general & internal medicine ,Electrical and Electronic Engineering ,Monitoring, Physiologic ,Data collection ,Clinical Deterioration ,Vital Signs ,business.industry ,medicine.disease ,Quality Improvement ,Computer Science Applications ,Clinical Alarms ,Models, Organizational ,Patient Safety ,Medical emergency ,business - Abstract
Clinical monitoring systems have been implemented in the inpatient hospital setting for decades, with little attention given to systems analysis or assessment of impact on clinician workflow or patient care. This study provides an example of how system-level design and analysis can be applied in this domain, with specific focus on early detection of patient deterioration to mitigate failure to rescue events. Wireless patient sensors and pulse oximetry-based surveillance system monitors with advanced display and information systems capabilities were introduced to 71 general care beds in two units. Nursing workflow was redesigned to integrate use of the new system and its features into patient assessment activities. Patient characteristics, vital sign documentation, monitor alarm, workflow, and system utilization data were collected and analyzed for the period five months before and five months after implementation. Comparison unit data were also collected and analyzed for the same periods. A survey pertaining to staff satisfaction and system performance was administered after implementation. Statistical analysis was performed to examine differences in the before and after data for the target and control units. The enhanced monitoring system received high staff satisfaction ratings and significantly improved key clinical elements related to early recognition of changes in patient state, including reducing average vital signs data collection time by 28%, increasing patient monitoring time (rate ratio 1.22), and availability and accuracy of patient information. Impact on clinical alarms was mixed, with no significant increase in clinical alarms per monitored hour.
- Published
- 2019
38. sST2 as a novel biomarker for the prediction of in-hospital mortality after coronary artery bypass grafting
- Author
-
David J. Malenka, Andrew R. Bohm, Devin M. Parker, Todd A. MacKenzie, Michael E. Rezaee, Jeremiah R. Brown, Anthony W. DiScipio, and Meagan E Stabler
- Subjects
Male ,medicine.medical_specialty ,Bypass grafting ,Health, Toxicology and Mutagenesis ,Clinical Biochemistry ,030204 cardiovascular system & hematology ,Biochemistry ,Article ,03 medical and health sciences ,Percutaneous Coronary Intervention ,Postoperative Complications ,0302 clinical medicine ,Risk Factors ,Internal medicine ,medicine ,Humans ,Hospital Mortality ,Coronary Artery Bypass ,Aged ,In hospital mortality ,business.industry ,Prognosis ,Interleukin-1 Receptor-Like 1 Protein ,medicine.anatomical_structure ,Cardiovascular Diseases ,030220 oncology & carcinogenesis ,Cardiology ,Biomarker (medicine) ,Female ,business ,Biomarkers ,Artery - Abstract
OBJECTIVES: Soluble suppression of tumorgenicity 2 (sST2) biomarker is an emerging predictor of adverse clinical outcomes, but its prognostic value for in-hospital mortality after coronary artery bypass grafting (CABG) is not well understood. This study measured the association between operative sST2 levels and in-hospital mortality after CABG. METHODS: A prospective cohort of 1,560 CABG patients were analysed from the Northern New England Cardiovascular Disease Study Group Biomarker Study. The primary outcome was in-hospital mortality after CABG surgery (n=32). RESULTS: After risk adjustment, patients in the third tercile of pre-, post- and pre-to-postoperative sST2 values experienced significantly greater odds of in-hospital death compared to patients in the first tercile of sST2 values. The addition of both postoperative and pre-to-postoperative sST2 biomarker significantly improved ability to predict in-hospital mortality status following CABG surgery, compared to using the EuroSCORE II mortality model alone, (c-statistic: 0.83 [95% CI: 0.75, 0.92], p-value 0.0213) and (c-statistic: 0.83 [95% CI: 0.75, 0.92], p-value 0.0215), respectively. CONCLUSION: sST2 values are associated with in-hospital mortality after CABG surgery and postoperative and pre-to-post operative sST2 values improve prediction. Our findings suggest that sST2 can be used as a biomarker to identify adult patients at greatest risk of in-hospital death after CABG surgery.
- Published
- 2019
39. REPORTED WEIGHT CHANGE IN OLDER ADULTS AND PRESENCE OF FRAILTY
- Author
-
Alexander J. Titus, Rebecca S. Crow, Courtney J. Stevens, Summer B. Cook, Todd A. MacKenzie, Curtis L. Petersen, and John A. Batsis
- Subjects
National Health and Nutrition Examination Survey ,business.industry ,Weight change ,General Medicine ,030204 cardiovascular system & hematology ,Logistic regression ,medicine.disease ,Obesity ,03 medical and health sciences ,0302 clinical medicine ,Primary outcome ,Weight loss ,Sarcopenia ,Medicine ,030212 general & internal medicine ,medicine.symptom ,business ,Weight gain ,Demography - Abstract
Objective: A 5% change in weight is a significant predictor for frailty and obesity. We ascertained how self-reported weight change over the lifespan impacts rates of frailty in older adults. Methods: We identified 4,984 subjects ≥60 years with body composition measures from the National Health and Nutrition Examination Survey. An adapted version of Fried’s frailty criteria was used as the primary outcome. Self-reported weight was assessed at time current,1 and 10 years earlier and at age 25. Weight changes between each time point were categorized as ≥ 5%, ≤5% or neutral. Logistic regression assessed the impact of weight change on the outcome of frailty. Results: Among 4,984 participants, 56.5% were female, mean age was 71.1 years, and mean BMI was 28.2kg/m2. A weight loss of ≥ 5% had a higher association with frailty compared to current weight, age 25 (OR 2.94 [1.72,5.02]), 10 years ago (OR 1.68 [1.05,2.69]), and 1 year ago (OR 1.55 [1.02,2.36]). Weight gain in the last year was associated with increased rate of frailty (1.59 [1.09,2.32]). Conclusion: There is an association between frailty and reported weight loss over time while only weight gain in the last year has an association with frailty.
- Published
- 2019
40. Statins associate with improved mortality among patients with certain histological subtypes of lung cancer
- Author
-
Matthew Ung, Christopher I. Amos, Chao Cheng, Todd A. MacKenzie, and Tracy Onega
- Subjects
Male ,Pulmonary and Respiratory Medicine ,Oncology ,Cancer Research ,medicine.medical_specialty ,Lung Neoplasms ,Statin ,medicine.drug_class ,Adenocarcinoma ,Article ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,Humans ,Medicine ,030212 general & internal medicine ,Lung cancer ,Survival analysis ,Aged ,Proportional Hazards Models ,Retrospective Studies ,business.industry ,Proportional hazards model ,Hazard ratio ,Retrospective cohort study ,medicine.disease ,Small Cell Lung Carcinoma ,United States ,Survival Rate ,030220 oncology & carcinogenesis ,Cohort ,Carcinoma, Squamous Cell ,Female ,Hydroxymethylglutaryl-CoA Reductase Inhibitors ,business ,SEER Program - Abstract
Objectives To measure the association between statin exposure and mortality in lung cancer patients belonging to different categories of histological subtype. Materials and methods A cohort of 19,974 individuals with incident lung cancer between 2007 and 2011 was identified using the SEER-Medicare linked database. Statin exposure both pre- and post-diagnosis was analyzed to identify a possible association with cancer-specific mortality in patients stratified by histological subtype. Intention-to-treat analyses and time-dependent Cox regression models were used to calculate hazard ratios and 95% confidence intervals (95% CIs) corresponding to statin exposure both pre- and post-diagnosis, respectively. Results Overall baseline statin exposure was associated with a decrease in mortality risk for squamous-cell carcinoma patients (HR = 0.89, 95% CI = 0.82–0.96) and adenocarcinoma patients (HR = 0.87, 95% CI = 0.82–0.94), but not among those with small-cell lung cancer. Post-diagnostic statin exposure was associated with prolonged survival in squamous-cell carcinoma patients (HR = 0.68, 95% CI = 0.59–0.79) and adenocarcinoma patients (HR = 0.78, 95% CI = 0.68–0.89) in a dose-dependent manner. Conclusion There is consistent evidence indicating that baseline or post-diagnostic exposure to simvastatin and atorvastatin is associated with extended survival in non-small-cell lung cancer subtypes. These results warrant further randomized clinical trials to evaluate subtype-specific effects of certain statins in patient cohorts with characteristics similar to those examined in this study.
- Published
- 2018
41. Prediction of Atypical Ductal Hyperplasia Upgrades Through a Machine Learning Approach to Reduce Unnecessary Surgical Excisions
- Author
-
Roberta M. diFlorio-Alexander, Saeed Hassanpour, Arief A. Suriawinata, Todd A. MacKenzie, Lia X. Harrington, and Katherine Trinh
- Subjects
0301 basic medicine ,Core needle ,Logistic regression ,Machine learning ,computer.software_genre ,Malignancy ,Cohort Studies ,Machine Learning ,03 medical and health sciences ,0302 clinical medicine ,Biopsy ,Original Report ,Humans ,Medicine ,Ductal Hyperplasia ,Medical diagnosis ,Hyperplasia ,medicine.diagnostic_test ,business.industry ,General Medicine ,medicine.disease ,Carcinoma, Intraductal, Noninfiltrating ,030104 developmental biology ,030220 oncology & carcinogenesis ,Cohort ,Hormonal therapy ,Female ,Artificial intelligence ,business ,computer - Abstract
Purpose Surgical excision is currently recommended for all occurrences of atypical ductal hyperplasia (ADH) found on core needle biopsies for malignancy diagnoses and treatment of lesions. The excision of all ADH lesions may lead to overtreatment, which results in invasive surgeries for benign lesions in many women. A machine learning method to predict ADH upgrade may help clinicians and patients decide whether combined active surveillance and hormonal therapy is a reasonable alternative to surgical excision. Methods The following six machine learning models were developed to predict ADH upgrade from core needle biopsy: gradient-boosting trees, random forest, radial support vector machine (SVM), weighted K-nearest neighbors (KNN), logistic elastic net, and logistic regression. The study cohort consisted of 128 lesions from 124 women at a tertiary academic care center in New Hampshire who had ADH on core needle biopsy and who underwent an associated surgical excision from 2011 to 2017. Results The best-performing models were gradient-boosting trees (area under the curve [AUC], 68%; accuracy, 78%) and random forest (AUC, 67%; accuracy, 77%). The top five most important features that determined ADH upgrade were age at biopsy, lesion size, number of biopsies, needle gauge, and personal and family history of breast cancer. Using the random forest model, 98% of all malignancies would have been diagnosed through surgical biopsies, whereas 16% of unnecessary surgeries on benign lesions could have been avoided (ie, 87% sensitivity at 45% specificity). Conclusion These results add to the growing body of support for machine learning models as useful aids for clinicians and patients in decisions about the clinical management of ADH.
- Published
- 2018
42. Spinal Manipulation vs Prescription Drug Therapy for Chronic Low Back Pain: Beliefs, Satisfaction With Care, and Qualify of Life Among Older Medicare Beneficiaries
- Author
-
Anupama Kizhakkeveettil, Serena Bezdjian, Eric L. Hurwitz, Andrew W.J. Toler, Daniel Rossi, Sarah Uptmor, Kayla Sagester, Maria Bangash, Todd A. MacKenzie, John D. Lurie, Ian Coulter, Scott Haldeman, and James M. Whedon
- Subjects
Manipulation, Spinal ,Prescription Drugs ,Treatment Outcome ,Quality of Life ,Humans ,Chiropractics ,Personal Satisfaction ,Medicare ,Low Back Pain ,United States ,Aged - Abstract
The objective of this study was to compare patients' perspectives on the use of spinal manipulative therapy (SMT) compared to prescription drug therapy (PDT) with regard to health-related quality of life (HRQoL), patient beliefs, and satisfaction with treatment.Four cohorts of Medicare beneficiaries were assembled according to previous treatment received as evidenced in claims data: SMT, PDT, and 2 crossover cohorts (where participants experienced both types of treatments). A total of 195 Medicare beneficiaries responded to the survey. Outcome measures used were a 0-to-10 numeric rating scale to measure satisfaction, the Low Back Pain Treatment Beliefs Questionnaire to measure patient beliefs, and the 12-item Short Form Health Survey to measure HRQoL.Recipients of SMT were more likely to be very satisfied with their care (84%) than recipients of PDT (50%; P = .002). The SMT cohort self-reported significantly higher HRQoL compared to the PDT cohort; mean differences in physical and mental health scores on the 12-item Short Form Health Survey were 12.85 and 9.92, respectively. The SMT cohort had a lower degree of concern regarding chiropractic care for their back pain compared to the PDT cohort's reported concern about PDT (P = .03).Among older Medicare beneficiaries with chronic low back pain, long-term recipients of SMT had higher self-reported rates of HRQoL and greater satisfaction with their modality of care than long-term recipients of PDT. Participants who had longer-term management of care were more likely to have positive attitudes and beliefs toward the mode of care they received.
- Published
- 2021
43. Long-Term Medicare Costs Associated With Opioid Analgesic Therapy vs Spinal Manipulative Therapy for Chronic Low Back Pain in a Cohort of Older Adults
- Author
-
James M. Whedon, Anupama Kizhakkeveettil, Andrew Toler, Todd A. MacKenzie, Jon D. Lurie, Serena Bezdjian, Scott Haldeman, Eric Hurwitz, and Ian Coulter
- Subjects
Analgesics, Opioid ,Manipulation, Spinal ,Humans ,Chiropractics ,Medicare ,Low Back Pain ,Chiropractic ,United States ,Article ,Aged - Abstract
OBJECTIVES: The purpose of this study was to compare Medicare healthcare expenditures for patients who received long-term treatment of chronic low back pain (cLBP) with either opioid analgesic therapy (OAT) or spinal manipulative therapy (SMT). METHODS: We conducted a retrospective observational study using a cohort design for analysis of Medicare claims data. The study population included Medicare beneficiaries enrolled under Medicare Parts A, B, and D from 2012 through 2016. We assembled cohorts of patients who received long-term management of cLBP with OAT or SMT (such as delivered by chiropractic or osteopathic practitioners) and evaluated the comparative effect of OAT vs SMT upon expenditures, using multivariable regression to control for beneficiary characteristics and measures of health status, and propensity score weighting and binning to account for selection bias. RESULTS: The study sample totaled 28,160 subjects, of whom 77% initiated long-term care of cLBP with OAT, and 23% initiated care with SMT. For care of low back pain specifically, average long-term costs for patients who initiated care with OAT were 58% lower than those who initiated care with SMT. However, overall long-term healthcare expenditures under Medicare were 1.87 times higher for patients who initiated care via OAT as compared to those initiated care with SMT (95% CI 1.65-2.11; p
- Published
- 2021
44. Factors associated with complete clip closure after endoscopic mucosal resection of large colorectal polyps
- Author
-
Jeffrey Gill, Maria Pellise, Stuart R. Gordon, Mouen A. Khashab, John M. Levenick, Muhammad K. Hasan, Harry R. Aslanian, Seth D. Crockett, Pooja A. Elias, Heiko Pohl, Matthew T. Moyer, Fadi Antaki, Douglas K. Pleskow, Omid Sanaei, B. Joseph Elmunzer, Amit Rastogi, Ryan Law, Oswaldo Ortiz, Abraham Mathew, Ian S. Grimm, Daniel von Renteln, Todd A. MacKenzie, Douglas K. Rex, Firas H. Al-Kawas, and Michael B. Wallace
- Subjects
Male ,medicine.medical_specialty ,Endoscopic Mucosal Resection ,Closure (topology) ,Colonic Polyps ,Endoscopic mucosal resection ,Resection ,03 medical and health sciences ,0302 clinical medicine ,Medicine ,Humans ,CLIPS ,computer.programming_language ,Aged ,business.industry ,Gastroenterology ,En bloc resection ,Polyp size ,Odds ratio ,Colonoscopy ,Surgical Instruments ,Surgery ,surgical procedures, operative ,030220 oncology & carcinogenesis ,030211 gastroenterology & hepatology ,Female ,business ,computer - Abstract
Background and study aim Delayed bleeding is a common adverse event following endoscopic mucosal resection (EMR) of large colorectal polyps. Prophylactic clip closure of the mucosal defect after EMR of nonpedunculated polyps larger than 20 mm reduces the incidence of severe delayed bleeding, especially in proximal polyps. This study aimed to evaluate factors associated with complete prophylactic clip closure of the mucosal defect after EMR of large polyps. Methods This is a post hoc analysis of the CLIP study (NCT01936948). All patients randomized to the clip group were included. Main outcome was complete clip closure of the mucosal resection defect. The defect was considered completely closed when no remaining mucosal defect was visible and clips were less than 1 cm apart. Factors associated with complete closure were evaluated in multivariable analysis. Results In total, 458 patients (age 65, 58 % men) with 494 large polyps were included. Complete clip closure of the resection defect was achieved for 338 polyps (68.4 %); closure was not complete for 156 (31.6 %). Factors associated with complete closure in adjusted analysis were smaller polyp size (odds ratio 1.06 for every millimeter decrease [95 % confidence interval 1.02–1.08]), good access (OR 3.58 [1.94–9.59]), complete submucosal lifting (OR 2.28 [1.36–3.90]), en bloc resection (OR 5.75 [1.48–22.39]), and serrated histology (OR 2.74 [1.35–5.56]). Conclusions Complete clip closure was not achieved for almost one in three resected large nonpedunculated polyps. While stable access and en bloc resection facilitate clip closure, most factors associated with clip closure are not modifiable. This highlights the need for alternative closure options and measures to prevent bleeding.
- Published
- 2020
45. Ischemic Stroke Occurs Less Frequently in Patients With COVID-19: A Multicenter Cross-Sectional Study
- Author
-
Nicos Labropoulos, Kimon Bekelis, Todd A. MacKenzie, Jonathan Skinner, Javaad Ahmad, Clemens M. Schirmer, Daniel R. Calnan, and Symeon Missios
- Subjects
Male ,medicine.medical_specialty ,Coronavirus disease 2019 (COVID-19) ,Cross-sectional study ,Original Contributions ,New York ,heart failure ,Coronary artery disease ,Clinical and Population Sciences ,Internal medicine ,Epidemiology ,medicine ,Odds Ratio ,Humans ,Mortality ,Propensity Score ,Aged ,Ischemic Stroke ,Advanced and Specialized Nursing ,Aged, 80 and over ,business.industry ,Case-control study ,COVID-19 ,Odds ratio ,Middle Aged ,medicine.disease ,infection ,Cross-Sectional Studies ,Logistic Models ,Heart failure ,Case-Control Studies ,Propensity score matching ,ComputingMethodologies_DOCUMENTANDTEXTPROCESSING ,Female ,Neurology (clinical) ,Cardiology and Cardiovascular Medicine ,business ,coronary artery disease - Abstract
Supplemental Digital Content is available in the text., Background and Purpose: The impact of coronavirus disease 2019 (COVID-19) on the occurrence of ischemic stroke has been the subject of increased speculation but has not been confirmed in large observational studies. We investigated the association between COVID-19 and stroke. Methods: We performed a cross-sectional study involving patients discharged from a healthcare system in New York State, from January to April 2020. A mixed-effects logistic regression analysis and a propensity score–weighted analysis were used to control for confounders and investigate the association of COVID-19 with ischemic stroke. Similar techniques were used to detect the impact of concurrent COVID-19 infection on unfavorable outcomes for patients with stroke. Results: Among 24 808 discharges, 2513 (10.1%) were diagnosed with COVID-19, and 566 (0.2%) presented with acute ischemic stroke. Patients diagnosed with COVID-19 were at one-quarter the odds of stroke compared with other patients (odds ratio, 0.25 [95% CI, 0.16–0.40]). This association was consistent in all age groups. Our results were robust in sensitivity analyses, including propensity score–weighted regression models. In patients presenting with stroke, concurrent infection with severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) was associated with higher case-fatality (odds ratio, 10.50 [95% CI, 3.54–31.18]) and a trend towards increased occurrence of discharge to rehabilitation (odds ratio, 2.45 [95% CI, 0.81–1.25]). Conclusions: Using a comprehensive cross-section of patients from a large NY-based healthcare system, we did not identify a positive association between ischemic stroke and COVID-19. However, patients with stroke with COVID-19 had worse outcomes compared with those without, with over a 9-fold increase in mortality. Although no definitive conclusions can be reached from our observational study, our data do not support the concerns for an epidemic of stroke in young adults with COVID-19.
- Published
- 2020
46. A New Efficient Method to Detect Genetic Interactions for Lung Cancer GWAS
- Author
-
Eric J. Duell, Todd A. MacKenzie, Xuemei Ji, Siting Li, Shanbeh Zienolddiny, Mark D. Thornquist, Olle Melander, Matthew B. Schabath, Christopher I. Amos, David C. Christiani, Susanne M. Arnold, Jiang Gui, Jennifer Luyapan, Dakai Zhu, Xiangjun Xiao, and Hans Brunnström
- Subjects
Adult ,Male ,lcsh:Internal medicine ,Genome-wide association study ,Lung Neoplasms ,Multifactor Dimensionality Reduction ,lcsh:QH426-470 ,Adolescent ,Genotype ,Computer science ,Single-nucleotide polymorphism ,Computational biology ,Polymorphism, Single Nucleotide ,Young Adult ,Machine learning ,Covariate ,Biomarkers, Tumor ,Genetics ,Humans ,SNP ,Genetic Predisposition to Disease ,lcsh:RC31-1245 ,Genetics (clinical) ,Survival analysis ,Aged ,Genetic association ,Aged, 80 and over ,Multifactor dimensionality reduction ,Genetic interactions ,Computational Biology ,Middle Aged ,Prognosis ,Gene Expression Regulation, Neoplastic ,Survival Rate ,lcsh:Genetics ,Technical Advance ,Case-Control Studies ,Càncer de pulmó ,Female ,Lung cancer ,Algorithms ,Genètica ,Type I and type II errors - Abstract
Background Genome-wide association studies (GWAS) have proven successful in predicting genetic risk of disease using single-locus models; however, identifying single nucleotide polymorphism (SNP) interactions at the genome-wide scale is limited due to computational and statistical challenges. We addressed the computational burden encountered when detecting SNP interactions for survival analysis, such as age of disease-onset. To confront this problem, we developed a novel algorithm, called the Efficient Survival Multifactor Dimensionality Reduction (ES-MDR) method, which used Martingale Residuals as the outcome parameter to estimate survival outcomes, and implemented the Quantitative Multifactor Dimensionality Reduction method to identify significant interactions associated with age of disease-onset. Methods To demonstrate efficacy, we evaluated this method on two simulation data sets to estimate the type I error rate and power. Simulations showed that ES-MDR identified interactions using less computational workload and allowed for adjustment of covariates. We applied ES-MDR on the OncoArray-TRICL Consortium data with 14,935 cases and 12,787 controls for lung cancer (SNPs = 108,254) to search over all two-way interactions to identify genetic interactions associated with lung cancer age-of-onset. We tested the best model in an independent data set from the OncoArray-TRICL data. Results Our experiment on the OncoArray-TRICL data identified many one-way and two-way models with a single-base deletion in the noncoding region of BRCA1 (HR 1.24, P = 3.15 × 10–15), as the top marker to predict age of lung cancer onset. Conclusions From the results of our extensive simulations and analysis of a large GWAS study, we demonstrated that our method is an efficient algorithm that identified genetic interactions to include in our models to predict survival outcomes.
- Published
- 2020
47. Developing Methods to Account for Bias from Unmeasured Sources When Analyzing Time Until a Health Event
- Author
-
Todd A. MacKenzie, Pablo Martínez-Camblor, Peter Scalia, James O'Malley, Douglas Hill, Doug Staiger, Glyn Elwyn, Philip P. Goodney, and Jesse A. Columbo
- Subjects
Computer science ,Event (relativity) ,Data mining ,computer.software_genre ,computer - Published
- 2020
48. Predicting colorectal polyp recurrence using time-to-event analysis of medical records
- Author
-
Lia X, Harrington, Jason W, Wei, Arief A, Suriawinata, Todd A, Mackenzie, and Saeed, Hassanpour
- Subjects
surgical procedures, operative ,otorhinolaryngologic diseases ,pathological conditions, signs and symptoms ,Articles ,neoplasms ,digestive system diseases - Abstract
Identifying patient characteristics that influence the rate of colorectal polyp recurrence can provide important insights into which patients are at higher risk for recurrence. We used natural language processing to extract polyp morphological characteristics from 953 polyp-presenting patients’ electronic medical records. We used subsequent colonoscopy reports to examine how the time to polyp recurrence (731 patients experienced recurrence) is influenced by these characteristics as well as anthropometric features using Kaplan-Meier curves, Cox proportional hazards modeling, and random survival forest models. We found that the rate of recurrence differed significantly by polyp size, number, and location and patient smoking status. Additionally, right-sided colon polyps increased recurrence risk by 30% compared to left-sided polyps. History of tobacco use increased polyp recurrence risk by 20% compared to never-users. A random survival forest model showed an AUC of 0.65 and identified several other predictive variables, which can inform development of personalized polyp surveillance plans.
- Published
- 2020
49. A Weight Loss Intervention Augmented by a Wearable Device in Rural Older Adults With Obesity: A Feasibility Study
- Author
-
Dawna Pidgeon, Matthew M. Clark, Curtis L. Petersen, Summer B. Cook, Francisco Lopez-Jimenez, Stephen J. Bartels, David Kotz, Rima Itani Al-Nimr, John A. Batsis, and Todd A. MacKenzie
- Subjects
Male ,Aging ,medicine.medical_specialty ,Waist ,Strength training ,THE JOURNAL OF GERONTOLOGY: Medical Sciences ,030209 endocrinology & metabolism ,Pilot Projects ,Rural Health ,03 medical and health sciences ,Wearable Electronic Devices ,0302 clinical medicine ,Weight loss ,Weight management ,Weight Loss ,Medicine ,Aerobic exercise ,Humans ,030212 general & internal medicine ,Obesity ,Exercise ,Aged ,Caloric Restriction ,business.industry ,medicine.disease ,Combined Modality Therapy ,Preferred walking speed ,Physical therapy ,Feasibility Studies ,Female ,Geriatrics and Gerontology ,medicine.symptom ,business ,Body mass index - Abstract
Background Older persons with obesity aged 65+ residing in rural areas have reduced access to weight management programs due to geographic isolation. The ability to integrate technology into health promotion interventions shows a potential to reach this underserved population. Methods A 12-week pilot in 28 older rural adults with obesity (body mass index [BMI] ≥ 30 kg/m2) was conducted at a community aging center. The intervention consisted of individualized, weekly dietitian visits focusing on behavior therapy and caloric restriction with twice weekly physical therapist-led group strengthening training classes in a community-based aging center. All participants were provided a Fitbit Flex 2. An aerobic activity prescription outside the strength training classes was provided. Results Mean age was 72.9 ± 5.3 years (82% female). Baseline BMI was 37.1 kg/m2, and waist circumference was 120.0 ± 33.0 cm. Mean weight loss (pre/post) was 4.6 ± 3.2 kg (4.9 ± 3.4%; p < .001). Of the 40 eligible participants, 33 (75%) enrolled, and the completion rate was high (84.8%). Objective measures of physical function improved at follow-up: 6-minute walk test improved: 35.7 ± 41.2 m (p < .001); gait speed improved: 0.10 ± 0.24 m/s (p = .04); and five-times sit-to-stand improved by 2.1 seconds (p < .001). Subjective measures of late-life function improved (5.2 ± 7.1 points, p = .003), as did Patient-Reported Outcome Measurement Information Systems mental and physical health scores (5.0 ± 5.7 and 4.4 ± 5.0, both p < .001). Participants wore their Fitbit 93.9% of all intervention days, and were overall satisfied with the trial (4.5/5.0, 1–5 low–high) and with Fitbit (4.0/5.0). Conclusions A multicomponent obesity intervention incorporating a wearable device is feasible and acceptable to older adults with obesity, and potentially holds promise in enhancing health.
- Published
- 2020
50. Association of Sex With Repair Type and Long-term Mortality in Adults With Abdominal Aortic Aneurysm
- Author
-
Art Sedrakyan, Bjoern D. Suckow, Todd A. MacKenzie, Jeremiah R. Brown, Philip P. Goodney, Niveditta Ramkumar, and Shipra Arya
- Subjects
Male ,medicine.medical_specialty ,MEDLINE ,Kaplan-Meier Estimate ,Aneurysm ,Sex Factors ,Risk Factors ,Internal medicine ,medicine ,Humans ,In patient ,Clinical registry ,Aorta ,Aged ,Retrospective Studies ,Surgical repair ,Aged, 80 and over ,business.industry ,Endovascular Procedures ,General Medicine ,medicine.disease ,Abdominal aortic aneurysm ,Long term mortality ,Female ,business ,Cohort study ,Aortic Aneurysm, Abdominal - Abstract
Sex-based differences exist in the prevalence and clinical presentation of abdominal aortic aneurysm (AAA). However, it is unclear if sex is associated with AAA repair type and long-term mortality.To investigate whether a sex-related difference exists in mortality risk after AAA repair owing to differences in repair type.This cohort study uses data from the Vascular Quality Initiative, a national clinical registry, and Medicare claims to investigate endovascular and surgical repair procedures performed between January 1, 2003, and September 30, 2015, in patients aged 65 years or older with AAA. The data were analyzed from October 1, 2018, to November 19, 2019.Sex of the patient.Endovascular (EVR) or open surgical AAA repair type and subsequent long-term, all-cause mortality.In this cohort study of 16 386 patients, 12 757 (77.9%) were men and 3629 (22.1%) were women. Women were more likely than men to be older (mean [SD] age, 77 [6.5] years vs 75 [6.6] years; P .001), active smokers (33% vs 28%; P .001), and to have smaller aneurysms (mean [SD] diameter, 57 [11.7] mm vs 59 [17.7] mm; P .001). Surgical AAA repair was performed in 27% (983 of 3629) of women compared with 18% (2328 of 12 757) of men (P .001). After inverse probability weighting for risk adjustment, women were more likely to receive open surgical repair than EVR repair (risk ratio, 1.65; 95% CI, 1.51-1.80). The 10-year unadjusted survival rate after EVR repair was 14% lower in women than in men (23% vs 37%; log-rank P .001), but the rates were comparable after open surgical repair (36% in men vs 32% in women; log-rank P = .22). Risk-adjusted analysis showed that women were associated with higher mortality rates after EVR repair (hazard ratio, 1.13; 95% CI, 1.03-1.24), whereas both men and women had a similar risk of death after open surgical repair (hazard ratio, 0.94; 95% CI, 0.84-1.06). After further stratification by symptom severity, higher risk of mortality among women was limited to elective EVR and open surgical repair for ruptured AAA.In this study, women were 65% more likely than men to undergo open surgical repair. After EVR repair, women were 13% more likely to die than men, although no sex-based difference in mortality was found after open surgical repair. The differential treatment benefit of EVR repair in women is concerning given the shift toward an EVR-first approach to AAA repair.
- Published
- 2020
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.