24 results on '"Abbott, Kevin"'
Search Results
2. Courtship strategies of male insects: when is learning advantageous?
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Dukas, Reuven, Clark, Colin W., and Abbott, Kevin
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Insects -- Analysis ,Zoology and wildlife conservation - Abstract
To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.anbehav.2006.05.002 Byline: Reuven Dukas, Colin W. Clark, Kevin Abbott Abstract: Experiments indicating learning in the context of courtship in fruit flies challenge the prevailing views that male insects are either indiscriminate or rely on innate rules for courtship. We investigated the conditions favouring learning during courtship in insects by using a model that compared a learning strategy to two alternatives, indiscriminate courtship and innate selectivity. Our analyses indicated that, under the two conditions of high encounter rates with females and long courtship durations, indiscriminate courtship resulted in much lower lifetime mating success than either selectivity or learning. Learning had moderate advantages over selectivity when encounter rates with females were high, when a large proportion of females were sexually receptive, and when acceptance rates by sexually receptive females were high. We predict that species in which such conditions commonly occur are most likely to show learning in the context of male courtship. Author Affiliation: (a) Animal Behaviour Group, Department of Psychology, Neuroscience & Behaviour, McMaster University, Canada (a ) Department of Mathematics, University of British Columbia, Canada Article History: Received 12 December 2005; Revised 4 March 2006; Accepted 5 May 2006 Article Note: (miscellaneous) MS. number: A10320
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- 2006
3. Honeybees consider flower danger in their waggle dance
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Abbott, Kevin R. and Dukas, Reuven
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Honeybee ,Zoology and wildlife conservation - Abstract
To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.anbehav.2009.05.029 Byline: Kevin R. Abbott, Reuven Dukas Abstract: Like most animals, honeybees, Apis mellifera, possess a suite of antipredatory adaptations used to defend their colony against intruders and to avoid flowers associated with predation risk. Honeybees also possess a remarkable ability to communicate the direction, distance and relative profitability of flower patches to hivemates using the well-studied waggle dance. Here we show that honeybees returning from foraging on dangerous flowers are less likely to perform the waggle dance and engage in fewer waggle runs than foragers returning from equally rewarding, safe flowers. Our results indicate that experienced foragers effectively steer naA[macron]ve recruits away from dangerous flowers and raise interesting questions as to how information about the reward and risk properties of patches are integrated into the waggle dance. Author Affiliation: Department of Psychology, Neuroscience and Behaviour, McMaster University, Canada Article History: Received 14 March 2009; Revised 9 April 2009; Accepted 18 May 2009 Article Note: (miscellaneous) MS. number: A09-00170
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- 2009
4. Acetylcysteine In Diabetes (AID): A randomized study of acetylcysteine for the prevention of contrast nephropathy in diabetics
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Coyle, Louis C., Rodriguez, Antonio, Jeschke, Robert E., Simon-Lee, Anabela, Abbott, Kevin C., and Taylor, Allen J.
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Kidney diseases -- Prevention ,Diabetes -- Research ,Diabetics ,Acetylcysteine ,Health - Abstract
To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ahj.2006.02.002 Byline: Louis C. Coyle, Antonio Rodriguez, Robert E. Jeschke, Anabela Simon-Lee, Kevin C. Abbott, Allen J. Taylor Abstract: Patients with diabetes mellitus (DM) are at increased risk of contrast-associated nephropathy irrespective of their baseline creatinine (Cr). We tested the efficacy of N-acetylcysteine (NAC) relative to hydration in unselected patients (irrespective of baseline Cr) with DM. Author Affiliation: Cardiology Service, Walter Reed Army Medical Center, Washington, DC Article History: Received 24 May 2005; Accepted 5 February 2006 Article Note: (footnote) The opinions or assertions herein are the private views of the authors and are not to be construed as reflecting the views of the United States Army, United States Navy, or the Department of Defense.
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- 2006
5. Cardiovascular risk assessment among potential kidney transplant candidates: approaches and controversies.
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Lentine KL, Hurst FP, Jindal RM, Villines TC, Kunz JS, Yuan CM, Hauptman PJ, Abbott KC, Lentine, Krista L, Hurst, Frank P, Jindal, Rahul M, Villines, Todd C, Kunz, Jeffrey S, Yuan, Christina M, Hauptman, Paul J, and Abbott, Kevin C
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Cardiovascular disease is the most common cause of death after kidney transplantation. However, uncertainties regarding the optimal assessment of cardiovascular risk in potential transplant candidates have produced controversy and inconsistency in pretransplantation cardiac evaluation practices. In this review, we consider the evidence supporting cardiac evaluation in kidney transplant candidates, generally focused on coronary artery disease, according to the World Health Organization principles for screening. The importance of pretransplant cardiac evaluation is supported by the high prevalence of coronary artery disease and the incidence and adverse consequences of acute coronary syndromes in this population. Testing for coronary artery disease may be performed noninvasively by using modalities that include nuclear myocardial perfusion studies and dobutamine stress echocardiography. These tests have prognostic value for mortality, but imperfect sensitivity and specificity for detecting angiographically defined coronary artery disease in patients with end-stage renal disease. Associations of angiographically-defined coronary artery disease with subsequent survival also are inconsistent, likely because plaque instability is more critical for infarction risk than angiographic stenosis. The efficacy and best methods of myocardial revascularization have not been examined in large contemporary clinical trials in patients with end-stage renal disease. Biomarkers, such as cardiac troponin, have prognostic value in end-stage renal disease, but require further study to determine clinical applications in directing more expensive and invasive cardiac evaluation. [ABSTRACT FROM AUTHOR]
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- 2010
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6. The impact of kidney transplantation on heart failure risk varies with candidate body mass index.
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Lentine, Krista L., Xiao, Huiling, Brennan, Daniel C., Schnitzler, Mark A., Villines, Todd C., Abbott, Kevin C., Axelrod, David, Snyder, Jon J., and Hauptman, Paul J.
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Background: The relationship of body mass index (BMI) with heart failure (HF) risk before and after kidney transplant is not well described. Methods: We examined United States Renal Data System records for 67,591 kidney transplant candidates (1995-2004) with Medicare insurance and BMI data at listing. Heart failure diagnoses were ascertained from Medicare billing claims. Body mass index was categorized per World Health Organization criteria. We modeled time-dependent associations (adjusted hazard ratio, aHR) of transplant with HF risk after listing compared with waiting in each BMI group by multivariable, stratified Cox regression. The time-dependent exposure variables partitioned relative risk of HF after transplant versus waiting into early (≤90 days) and late (>90 days) posttransplant periods. Results: The BMI distribution of listed candidates was as follows: 3.7% under, 40.4% normal, 32.0% over, 16.2% obese, and 7.7% morbidly obese weight. The prevalence of HF among patients awaiting transplant reached 57.4% by 3 years. Deceased-donor transplant was associated with increased early HF risk compared with continued waiting—aHRs ranged from 2.23 for normal-BMI to 2.82 for morbidly obese patients. However, transplant reduced the risk of HF in the late posttransplant period from 54% (aHR 0.46) in normal-BMI to 32% (aHR 0.68) for morbidly obese patients. Relative benefits were largest for normal-weight candidates who received live-donor transplants (aHR 0.31). Conclusions: Heart failure risk improves in obese patients in the long term after kidney transplant, but not as much as for nonobese patients. There is need for close monitoring and for new strategies to reduce HF risk in obese patients before and after transplant. [Copyright &y& Elsevier]
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- 2009
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7. Acute respiratory distress syndrome following renal transplantation. (Critical care outcomes: 2:30pm-4:00pm)
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Shorr, Andrew F., Abbott, Kevin C., and Agadoa, Lawrence Y.
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Health - Abstract
PURPOSE: Acute respiratory distress syndrome (ARDS) is associated with significant morbidity and mortality. Patients undergoing renal transplantation (RT) may be at increased risk for developing ARDS because the immunosuppression needed [...]
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- 2002
8. Epidemiology of Dialysis Patients and Heart Failure Patients.
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Kalantar-Zadeh, Kamyar, Abbott, Kevin C., Kronenberg, Florian, Anker, Stefan D., Horwich, Tamara B., and Fonarow, Gregg C.
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HEART failure patients ,HEMODIALYSIS patients ,CARDIOVASCULAR diseases risk factors ,PROTEIN-energy malnutrition ,CACHEXIA ,HYPERCHOLESTEREMIA ,HYPERTENSION ,OBESITY ,HOMOCYSTEINE ,EPIDEMIOLOGY - Abstract
The epidemiology of maintenance dialysis patients and heart failure patients has striking similarities. Both groups have a high prevalence of comorbid conditions, a high hospitalization rate, a low self-reported quality of life, and an excessively high mortality risk, mostly because of cardiovascular causes. Observational studies in both dialysis and heart failure patients have indicated the lack of a significant association between the traditional cardiovascular risk factors and mortality, or the existence of a paradoxic or reverse association, in that obesity, hypercholesterolemia, and hypertension appear to confer survival advantages. The time discrepancy between the 2 sets of risk factors, that is, overnutrition (long-term killer) versus undernutrition (short-term killer) may explain the overwhelming role of malnutrition, inflammation, and cachexia in causing the reverse epidemiology, which may exist in more than 20 million Americans. We have reviewed the opposing views about the concept of reverse epidemiology in dialysis and heart failure patients, the recent Die Deutsche Diabetes Dialyze study findings, and the possible role of racial disparities. Contradictory findings on hyperhomocysteinemia in dialysis patients are reviewed in greater details as a possible example of publication bias. Additional findings related to intravenous iron and serum ferritin, calcium, and leptin levels in dialysis patients may enhance our understanding of the new paradigm. The association between obesity and increased death risk in kidney transplanted patients is reviewed as an example of the reversal of reverse epidemiology. Studying the epidemiology of dialysis patients as the archetypical population with such paradoxic associations may lead to the development of population-specific guidelines and treatment strategies beyond the current Framingham cardiovascular risk factor paradigm. [ABSTRACT FROM AUTHOR]
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- 2006
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9. Differing Manifestations of Hepatitis C and Tacrolimus on Hospitalized Diabetes Mellitus Occurring after Kidney Transplantation
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Abbott, Kevin C., Bernet, Victor J., Agodoa, Lawrence Y., and Yuan, Christina M.
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HEPATITIS C , *TACROLIMUS , *DIABETES , *KIDNEY transplantation - Abstract
Purpose: Previous studies suggest the association of recipient hepatitis C seropositivity (HCV+) and use of tacrolimus (TAC) with post-transplant diabetes mellitus (PTDM) may differ by manifestations of type I or type II diabetes, but this has not been assessed in the era of current immunosuppression. Methods: We performed a retrospective cohort study of 10,342 Medicare primary renal transplantation recipients without evidence of diabetes at the time of listing in the United States Renal Data System between January 1, 1998 and July 31, 2000, followed until December 31, 2000. Outcomes were hospitalizations for a primary diagnosis of diabetic ketoacidosis (DKA) or hyperglycemic hyperosmolar syndrome (HHS). Cox regression analysis was used to calculate adjusted hazard ratios (AHR) for time to DKA or HHS, stratified by diabetes status at the time of transplant. Results: In Cox regression analysis, use of TAC at discharge was independently associated with shorter time to DKA (AHR, 1.88; 95% CI, 1.05–3.37, p =0.034) but not HHS. In contrast, recipient HCV+ was independently associated with shorter time to HHS (AHR, 3.90; 1.59–9.60, p =.003), but not DKA. There was no interaction between TAC and HCV+ for either outcome. Conclusion: These results confirm earlier findings that TAC and HCV+ may mediate the risk of PTDM through different mechanisms, even in the modern era. [Copyright &y& Elsevier]
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- 2005
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10. Survival advantages of obesity in dialysis patients.
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Kalantar-Zadeh, Kamyar, Abbott, Kevin C., Salahudeen, Abdulla K., Kilpatrick, Ryan D., and Horwich, Tamara B.
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In the general population, a high body mass index (BMI; in kg/m
2 ) is associated with increased cardiovascular disease and all-cause mortality. However, the effect of overweight (BMI: 25-30) or obesity (BMI: >30) in patients with chronic kidney disease (CKD) undergoing maintenance hemodialysis (MHD) is paradoxically in the opposite direction; ie, a high BMI is associated with improved survival. Although this "reverse epidemiology" of obesity or dialysis-risk-paradox is relatively consistent inMHDpatients, studies in CKD patients undergoing peritoneal dialysis have yielded mixed results. Growing confusion has developed among physicians, some of whom are no longer confident about whether to treat obesity in CKD patients. A similar reverse epidemiology of obesity has been described in geriatric populations and in patients with chronic heart failure (CHF). Possible causes of the reverse epidemiology of obesity include a more stable hemodynamic status, alterations in circulating cytokines, unique neurohormonal constellations, endotoxinlipoprotein interaction, reverse causation, survival bias, time discrepancies among competitive risk factors, and malnutritioninflammation complex syndrome. Reverse epidemiology may have significant clinical implications in the management of dialysis, CHF, and geriatric patients, ie, populations with extraordinarily high mortality. Exploring the causes and consequences of the reverse epidemiology of obesity in dialysis patients can enhance our insights into similar paradoxes observed for other conventional risk factors, such as blood pressure and serum cholesterol and homocysteine concentrations, and in other populations such as those with CHF, advanced age, cancer, or AIDS. Weight-gaining interventional studies in dialysis patients are urgently needed to ascertain whether they can improve survival and quality of life. [ABSTRACT FROM AUTHOR]- Published
- 2005
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11. CLINICAL NEPHROLOGY - EPIDEMIOLOGY - CLINICAL TRIALS Body mass index, dialysis modality, and survival: Analysis of the United States Renal Data System Dialysis Morbidity and Mortality Wave II Study.
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Abbott, Kevin C., Glanton, Christopher W., Trespalacios, Fernando C., Oliver, David K., Ortiz, Maria I., Agodoa, Lawrence Y., Cruess, David F., and Kimmel, Paul L.
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KIDNEY diseases , *OBESITY , *HEMODIALYSIS patients , *REGRESSION analysis , *MORTALITY , *SURVIVAL analysis (Biometry) - Abstract
Body mass index, dialysis modality, and survival: Analysis of the United States Renal Data System Dialysis Morbidity and Mortality Wave II Study. Background. The impact of obesity on survival in end-stage renal disease (ESRD) patients as related to dialysis modality (i.e., a direct comparison of hemodialysis with peritoneal dialysis) has not been assessed adjusting for differences in medication use, follow-up ≥2 years, or accounting for changes in dialysis modality. Methods. We performed a retrospective cohort study of the United States Renal Data System (USRDS) Dialysis Morbidity and Mortality Wave II Study (DMMS) patients who started dialysis in 1996, and were followed until October 31 2001. Cox regression analysis was used to model adjusted hazard ratios (AHR) for mortality for categories of body mass index (BMI), both as quartiles and as ≥30 kg/m2 vs. lower. Because such a large proportion of peritoneal dialysis patients changed to hemodialysis during the study period (45.5%), a sensitivity analysis was performed calculating survival time both censoring and not censoring on the date of change from peritoneal dialysis to hemodialysis. Results. There were 1675 hemodialysis and 1662 peritoneal dialysis patients. Among hemodialysis patients, 5-year survival for patients with BMI ≥30 kg/m2 was 39.8% vs. 32.3% for lower BMI ( P < 0.01 by log-rank test). Among peritoneal dialysis patients, 5-year survival for patients with BMI ≥30 kg/m2 was 38.7% vs. 40.4% for lower BMI ( P > 0.05 by log-rank test). In adjusted analysis, BMI ≥ 30 kg/m2 was associated with improved survival in hemodialysis patients (AHR 0.89; 95% CI 0.81, 0.99; P= 0.042) but not peritoneal dialysis patients (AHR = 0.99; 95% CI, 0.86, 1.15; P= 0.89). Results were not different on censoring of change from peritoneal dialysis to hemodialysis. Conclusion. We conclude that any survival advantage associated with obesity among chronic dialysis patients is significantly less likely for peritoneal dialysis patients, compared to hemodialysis patients. [ABSTRACT FROM AUTHOR]
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- 2004
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12. Hospitalized avascular necrosis after renal transplantation in the United States.
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Abbott, Kevin C., Oglesby, Robert J., and Agodoa, Lawrence Y.
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KIDNEY transplantation , *NECROSIS - Abstract
Hospitalized avascular necrosis after renal transplantation in the United States. Background. The national incidence of and risk factors for hospitalized avascular necrosis (AVN) in renal transplant recipients has not been reported. Methods. This historical cohort study consisted of 42,096 renal transplant recipients enrolled in the United States Renal Data System (USRDS) between 1 July 1994 and 30 June 1998. The data source was USRDS files through May 2000. Associations with hospitalizations for a primary diagnosis of AVN (ICD-9 codes 733.4x) within three years after renal transplant were assessed in an intention-to-treat design by Cox regression analysis. Results. Recipients had a cumulative incidence of 7.1 episodes/1000 person-years from 1994 to 1998. The two-year incidence of AVN did not change significantly over time. Eighty-nine percent of the cases of AVN were due to AVN of the hip (733.42) and 60.2% of patients with AVN underwent total hip arthroplasty (THA); these percentages did not change significantly over time. In the Cox regression analysis, an earlier year of transplant, African American race [adjusted hazard ratio (AHR), 1.65, 95% confidence interval (CI) 1.33 to 2.03], allograft rejection (AHR 1.67, 95% CI 1.35 to 2.07), peritoneal dialysis (vs. hemodialysis; AHR 1.44, 95% CI 1.15 to 1.81), and diabetes (AHR 0.41, 95% CI 0.27 to 0.64) were the only factors independently associated with hospitalizations for AVN. Conclusions. The incidence of AVN did not decline significantly over time in the renal transplant population. Patients with allograft rejection, African American race, peritoneal dialysis and earlier date of transplant were at the highest risk of AVN, while diabetic recipients were at a decreased risk. [ABSTRACT FROM AUTHOR]
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- 2002
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13. Hospitalizations for Cytomegalovirus Disease after Renal Transplantation in the United States
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Abbott, Kevin C., Hypolite, Iman O., Viola, Rebecca, Poropatich, Ronald K., Hshieh, Paul, Cruess, David, Hawkes, Clifton A., and Agodoa, Lawrence Y.
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KIDNEY transplantation , *CYTOMEGALOVIRUS diseases , *DISEASE risk factors - Abstract
PURPOSE: Risk factors, sites, and mortality of hospitalized cytomegalovirus (CMV) disease in renal transplant recipients have not been studied in a national population.METHODS: Therefore, 33,479 renal transplant recipients in the United States Renal Data System from 1 July 1, 1994 to June 30, 1997 were analyzed in an historical cohort study of patients with a primary discharge diagnosis of CMV disease (ICD9 Code 078.5x).RESULTS: Renal transplant recipients had an incidence density of hospitalized CMV disease of 1.26/100 person years, and 79% of hospitalizations for CMV disease occurred in the first six months post transplant. The leading manifestation of hospitalized infection was pneumonia (17%). In logistic regression analysis controlling for transplant era, pre-transplant dialysis ⩾ 6 months, maintenance mycophenolate mofetil (MMF) therapy, and allograft rejection, but not induction antibody therapy, were significantly associated with hospitalized CMV disease. Compared with recipients with negative CMV serology (R-) who had donor kidneys with negative CMV serology (D−), D+/R− had the highest risk of hospitalization for CMV disease [adjusted odds ratio (AOR) 5.19, 95% confidence interval (CI) 3.89–6.93] followed by D+/R+ recipients, whereas D−/R+ were not at significantly increased risk. In Cox Regression analysis the relative risk of death associated with hospitalized CMV disease was 1.32 (95% CI 1.02–1.71).CONCLUSIONS: Even in modern era, renal transplant recipients were at high risk for hospitalizations for CMV disease, which were associated with decreased patient survival. Current prophylactic measures have apparently not reduced the high risk of D+/R− recipients. Prolonged pre-transplant dialysis and maintenance MMF should also be considered risk factors for hospitalized CMV infection, and prospective trials of prophylactic antiviral therapy should be performed in these subgroups. [Copyright &y& Elsevier]
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- 2002
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14. Hospitalized Congestive Heart Failure after Renal Transplantation in the United States
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Abbott, Kevin C., Hypolite, Iman O., Hshieh, Paul, Cruess, David, Taylor, Allen J., and Agodoa, Lawrence Y.
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HEART failure , *KIDNEY transplantation , *DIABETES - Abstract
PURPOSE: African Americans have increased risk for congestive heart failure (CHF) compared to Caucasians in the general population, but the risk of CHF in African American renal transplant recipients has not been studied in a national renal transplant population.METHODS: Therefore, 33,479 renal transplant recipients in the United States Renal Data System (USRDS) from 1 July, 1994 to 30 June, 1997 were analyzed in an historical cohort study of the incidence, associated factors, and mortality of hospitalizations with a primary discharge diagnosis of CHF [International Classification of Diseases-9 (ICD9) Code 428.x].RESULTS: African American renal transplant recipients had increased age-adjusted risk of hospitalizations for congestive heart failure compared to African Americans in the general population [rate ratio 4.60, 95% confidence interval (CI) 4.59–4.62]. In logistic regression analysis, African American recipients had increased risk of congestive heart failure after renal transplantation, independent of other factors. Among other significant factors associated with congestive heart failure, the strongest were graft loss and allograft rejection. No maintenance immunosuppressive medications were associated with CHF. In Cox regression analysis patients hospitalized for CHF had increased all-cause mortality compared with all other recipients (hazard ratio 3.69, 95% CI, 2.23–6.10), but African American recipients with CHF were not at significantly increased risk of mortality compared to Caucasian recipients with CHF.CONCLUSIONS: African Americans recipients were at high risk for CHF after transplant independent of other factors. The reasons for this increased risk should be the subject of further study. All potential transplant recipients should receive particular attention for the diagnosis and prevention of CHF in the transplant evaluation process, which includes preservation of allograft function. [Copyright &y& Elsevier]
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- 2002
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15. The paradox of the "body mass index paradox" in dialysis patients: associations of adiposity with inflammation.
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Beddhu, Srinivasan, Ramkumar, Nirupama, Samore, Matthew H., Kalantar-Zadeh, Kamyar, Abbott, Kevin C., and Salahudeen, Abdulla K.
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- 2005
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16. Re: Ought dialysis patients with atrial fibrillation be treated with oral anticoagulants?
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Abbott, Kevin C.
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- 2005
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17. Reverse epidemiology and obesity in maintenance dialysis patients.
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Abbott, Kevin C.
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OBESITY , *HEMODIALYSIS patients , *GANGRENE - Abstract
The authors cite several studies to support a uniform effect of obesity on survival. However, there have been some American studies that show the effect of obesity on survival in chronic dialysis patients is far from uniform. The specific cause of death that was significantly more common among obese women was death due to infection, predominantly vascular access infection and extremity gangrene. Therefore, "reverse epidemiology" notwithstanding, an opportunity to improve the health of patients on chronic dialysis. Similar approaches may successfully lead to reversal of the reverse epidemiology and a return to traditional epidemiology.
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- 2003
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18. Pediatric Urinary Stone Disease in the United States: The Urologic Diseases in America Project.
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Ward, Julia B., Feinstein, Lydia, Pierce, Casey, Lim, John, Abbott, Kevin C., Bavendam, Tamara, Kirkali, Ziya, Matlaga, Brian R., and NIDDK Urologic Diseases in America Project
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URINARY organ diseases , *DISEASE progression , *AGE differences , *BUSINESS insurance , *U.S. states , *COMPARATIVE studies , *DATABASES , *ETHNIC groups , *LONGITUDINAL method , *RESEARCH methodology , *MEDICAL cooperation , *RESEARCH , *RESEARCH funding , *URINARY calculi , *EVALUATION research , *DISEASE prevalence , *RETROSPECTIVE studies - Abstract
Objective: To examine the recent epidemiology of pediatric urinary stone disease (USD) in the United States.Methods: We utilized the 2004-2016 Optum© Clinformatics® Data Mart database, a de-identified adjudicated administrative health claims database that includes 15-18 million individuals covered annually by commercial insurance in all 50 US states. The analysis included 12,739,125 children aged 0-18 years. We calculated annual rates of USD, ambulatory visits, and procedures, and the prevalence of prescription fills.Results: The 2005-2016 USD rate was 59.5 cases per 100,000 person-years. The annual rate rose gradually from 2005 to a peak of 65.2 cases per 100,000 person-years in 2011. The USD rate increased with increasing age, and was highest among females compared to males, non-Hispanic Whites compared to other race/ethnic groups, and those residing in the South compared to other geographic regions. The overall 2005-2016 rate in the 120 days following a USD episode was 1.9 for ambulatory visits, 0.24 for surgical procedures, and 1.1 for imaging procedures. Ureteroscopy was the most common surgical procedure and CT scan was the most common imaging procedures, although ultrasound utilization increased over time. Medications were filled in 46.9% of cases, and use was lowest among males (43.1%), Asians (34.8%), and in the Northeast (34.3%). Opiate agonists were the most prevalent prescription (39.9%).Conclusion: Our study provides one of the most comprehensive examinations of pediatric USD to date, demonstrating shifting rates and treatment patterns over time, as well as differences by age, gender, race/ethnicity, and geographic region. [ABSTRACT FROM AUTHOR]- Published
- 2019
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19. Association of Race and Poverty With Mortality Among Nursing Home Residents on Maintenance Dialysis.
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Nee, Robert, Thurlow, John S., Norris, Keith C., Yuan, Christina, Watson, Maura A., Agodoa, Lawrence Y., and Abbott, Kevin C.
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TREATMENT of chronic kidney failure , *CHRONIC kidney failure , *CONFIDENCE intervals , *HEALTH services accessibility , *HEMODIALYSIS , *HEMODIALYSIS patients , *LONGITUDINAL method , *MEDICAID , *MEDICARE , *NURSING home residents , *POVERTY , *RACE , *REGRESSION analysis , *SURVIVAL , *PSYCHOSOCIAL factors , *SOCIOECONOMIC factors , *PROPORTIONAL hazards models , *RETROSPECTIVE studies ,MORTALITY risk factors - Abstract
The association of race, ethnicity, and socioeconomic factors with survival rates of nursing home (NH) residents with treated end-stage renal disease (ESRD) is unclear. We examined whether race/ethnicity, ZIP code–level, and individual-level indicators of poverty relate to mortality of NH residents on dialysis. Retrospective cohort study. Using the United States Renal Data System database, we identified 56,194 nursing home residents initiated on maintenance dialysis from January 1, 2007 through December 31, 2013, followed until May 31, 2014. We evaluated baseline characteristics of the NH cohort on dialysis, including race and ethnicity. We assessed the Medicare-Medicaid dual eligibility status as an indicator of individual-level poverty and ZIP code–level median household income (MHI) data. We conducted Cox regression analyses with all-cause mortality as the outcome variable, adjusted for clinical and sociodemographic factors including end-of-life preferences. Adjusted Cox analysis showed a significantly lower risk of death among black vs nonblack NH residents [adjusted hazard ratio (AHR) 0.91, 95% confidence interval (CI) 0.89, 0.94]. Dual-eligibility status was significantly associated with lower risk of death compared to those with Medicare alone (AHR 0.80, 95% CI 0.78, 0.82). Compared to those in higher MHI quintile levels, NH ESRD patients in the lowest quintile were significantly associated with higher risk of death (AHR 1.09, 95% CI 1.06, 1.13). Black and Hispanic NH residents on dialysis had an apparent survival advantage. This "survival paradox" occurs despite well-documented racial/ethnic disparities in ESRD and NH care and warrants further exploration that could generate new insights into means of improving survival of all NH residents on dialysis. Area-level indicator of poverty was independently associated with mortality, whereas dual-eligibility status for Medicare and Medicaid was associated with lower risk of death, which could be partly explained by improved access to care. [ABSTRACT FROM AUTHOR]
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- 2019
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20. Incidence, Predictors and Associated Outcomes of Renal Cell Carcinoma in Long-term Dialysis Patients
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Hurst, Frank P., Jindal, Rahul M., Fletcher, James J., Dharnidharka, Vikas, Gorman, Greg, Lechner, Brent, Nee, Robert, Agodoa, Lawrence Y., and Abbott, Kevin C.
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RENAL cell carcinoma , *DISEASE incidence , *DIALYSIS (Chemistry) , *CYSTS (Pathology) , *HEALTH outcome assessment - Abstract
We carried out an analysis of the United States Renal Data System to determine the incidence, risk factors and prognosis of renal cell carcinoma (RCC) in a national population of patients receiving incident long-term dialysis. In Cox regression, male gender, older age, end-stage renal disease caused by obstruction, tuberous sclerosis, focal segmental glomerulosclerosis, as well as acquired renal cysts, were independently associated with RCC. Most cases of RCC in incident long-term dialysis patients occurred in patients without acquired renal cysts. A diagnosis of RCC was associated with increased risk of subsequent mortality overall and in all high-risk groups. [ABSTRACT FROM AUTHOR]
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- 2011
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21. Renal cell carcinoma as a cause of end-stage renal disease in the United States: Patient characteristics and survival.
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Stiles, Kevin P., Moffatt, Michael J., Agodoa, Lawrence Y., Swanson, S. John, and Abbott, Kevin C.
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RENAL cell carcinoma , *RENAL cancer , *KIDNEY diseases , *CHRONIC kidney failure - Abstract
Renal cell carcinoma as a cause of end-stage renal disease in the United States: Patient characteristics and survival. Background. The patient characteristics and mortality associated with renal cell carcinoma (RCC) as a cause of end-stage renal disease (ESRD) have not been characterized for a national population. Methods. An historical cohort study of renal cell carcinoma (RCC) was conducted from April 1, 1995, to December 31, 1999. Included were 360,651 patients in the United States Renal Data System (USRDS) who were initiated on ESRD therapy with valid causes of ESRD. Results. Of the study population, 1646 patients (0.5%) had RCC. The mean age of patients with RCC was 66.8 ± 14.6 years versus 61.3 ± 16.4 years for patients with other causes of ESRD (P < 0.01 by Student t test). The unadjusted 3-year survival (censored at the date of renal transplantation) of patients with RCC during the study period was 23% versus 36% in all other patients [adjusted hazard ratio (AHR), 1.10, 95% confidence interval (CI) 1.02–1.19, P = 0.019 by Cox regression]. However, patients with RCC who underwent nephrectomy (bilateral or unilateral) had significantly better survival compared to RCC patients who did not (AHR, 0.73, 95% CI, 0.63–0.85, P < 0.01), and their survival was not significantly different in comparison with nondiabetic ESRD patients. Bilateral nephrectomy (vs. unilateral) was not associated with any difference in adjusted mortality. Conclusion. Among patients with ESRD, the demographics of those with RCC were similar to those of patients with RCC in the general population. Overall, patients with RCC had decreased survival compared to patients with other causes of ESRD; those who underwent nephrectomy had significantly better survival than those who did not, with survival comparable to patients with nondiabetic ESRD. [ABSTRACT FROM AUTHOR]
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- 2003
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22. Factors associated with improved short term survival in obese end stage renal disease patients.
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Glanton CW, Hypolite IO, Hshieh PB, Agodoa LY, Yuan CM, Abbott KC, Glanton, Christopher W, Hypolite, Iman O, Hshieh, Paul B, Agodoa, Lawrence Y, Yuan, Christina M, and Abbott, Kevin C
- Abstract
Purpose: In contrast to its role in the general population, obesity, defined as body mass index (BMI) > or = 30 kg/m(2), has been associated with improved survival in patients with end stage renal disease (ESRD). This apparent benefit has not been explained.Methods: Using the United States Renal Data System (USRDS), we performed an historical cohort study on 151,027 patients initiated on ESRD therapy between January 1, 1995 and June 30, 1997, who never received renal transplants, and who had information sufficient to calculate BMI. We explored the association of various comorbidities present at the time of dialysis initiation (from HCFA Form 2728) with the presence of obesity by logistic regression, and the association of obesity with patient survival, including specific causes of death, by Cox regression adjusting for factors known to be associated with survival in this population.Results: Obese patients had an unadjusted two-year survival of 68% compared with 58% for non obese patients. Obesity was independently associated with a reduced risk of mortality among chronic dialysis patients (adjusted hazard ratio (AHR) 0.75, 95% confidence interval, 0.72-0.78), after controlling for all comorbidities and risk factors. However, there were significantly adverse interactions among whites (AHR 1.22, 1.14-1.30, across all causes of death) and females (AHR 1.12, 1.04-1.20, entirely due to an increased risk of infectious death).Conclusions: Obesity in patients presenting with ESRD is associated independently with reduced all cause mortality; however, the relationship is complex and is stronger in African Americans. In addition, subgroup analysis suggests that obesity is associated with increased risk of infectious death in females. [ABSTRACT FROM AUTHOR]- Published
- 2003
- Full Text
- View/download PDF
23. Impact of renal transplantation on survival in end-stage renal disease patients with elevated body mass index.
- Author
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Glanton, Christopher W., Kao, Tzu-Cheg, Cruess, David, Agodoa, Lawrence Y.C., and Abbott, Kevin C.
- Subjects
- *
CHRONIC kidney failure , *KIDNEY transplantation - Abstract
Impact of renal transplantation on survival in end-stage renal disease patients with elevated body mass index. Background. Cadaveric renal transplantation is associated with a survival advantage compared with dialysis patients remaining on the renal transplantation waiting list, but this advantage has not been confirmed in obese end-stage renal disease (ESRD) patients. Methods. Using data from the USRDS, we studied 7521 patients who presented with ESRD from 1 April 1995 to 29 June 1999 and later enrolled on the renal transplantation waiting list with body mass indices (BMI) ≥30 kg/m2 at the time of presentation to ESRD, and followed until 6 November 2000. Recipients of preemptive renal transplantation or organs other than kidneys were excluded. Cox non-proportional hazards regression models were used to calculate adjusted, time-dependent hazard ratios (HR) for time to death in a given patient during the study period, controlling for renal transplantation, demographics and comorbidities (Form 2728). Results. The incidence of mortality was 3.3 episodes per 100 patient-years (PY) in cadaveric renal transplantation and 1.9/100 PY in living donor renal transplantation compared with 6.6 episodes/100 PY in all patients on the transplant waiting list. In comparison to maintenance dialysis, both recipients of solitary cadaveric kidneys (HR 0.39, 95% CI 0.33 to 0.47), and recipients of living donor kidneys (HR 0.23, 95% CI 0.16 to 0.34) had statistically significant improved survival. A benefit of cadaveric renal transplantation did not apply to patients with BMI ≥41 kg/m2 (HR 0.47, 95% CI, 0.17 to 1.25, P = 0.13). Conclusions. Obese patients on the renal transplant waiting list had a significantly lower risk of mortality after renal transplantation compared with those remaining on dialysis. [ABSTRACT FROM AUTHOR]
- Published
- 2003
- Full Text
- View/download PDF
24. Incident acute coronary syndromes in chronic dialysis patients in the United States[sup 1].
- Author
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Trespalacios, Fernando C., Taylor, Allen J., Agodoa, Lawrence Y., and Abbott, Kevin C.
- Subjects
- *
ACE inhibitors , *ADRENERGIC beta blockers , *CHOLESTEROL - Abstract
Background. Patients on dialysis have a disproportionately high rate of cardiovascular disease (CVD). However, the incidence and risk factors for incident acute coronary syndromes (ACS) have not been previously assessed in dialysis patients. Methods. We analyzed the United States Renal Data System (USRDS) Dialysis Morbidity and Mortality Study (DMMS) Wave II in a historical cohort study of ACS. Data from 3374 patients who started dialysis in 1996 with valid follow-up times were available for analysis, censored at the time of renal transplantation and followed until March 2000. Cox regression analysis was used to model factors associated with time to first hospitalization for ACS (ICD9 code 410.x or 411.x) adjusted for comorbidities, demographic factors, baseline laboratory values, blood pressures and cholesterol levels, type of vascular access, dialysis adequacy, and cardioprotective medications (angiotensin-converting enzyme inhibitors, calcium channel blockers, HMG-CoA reductase inhibitors (statins), beta blockers, and aspirin). Follow-up was 2.19 ± 1.14 years. Results. The incidence of ACS was 29/1000 person-years. Factors associated with ACS were older age, the extreme high and low ranges of serum cholesterol level, history of coronary heart disease (CHD), male gender, and diabetes. No cardioprotective medications including statins had a significant association with ACS in this study. However, medications known to reduce mortality after ACS were used in less than 50% of patients with known CHD at the start of the study, and statins were used in less than 10% of patients with CHD. Conclusions. Dialysis patients had similar risk factors for ACS compared to the general population. Cardioprotective medications were not associated with a significant benefit, possibly due to their striking underutilization in this at-risk population. [ABSTRACT FROM AUTHOR]
- Published
- 2002
- Full Text
- View/download PDF
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