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Study Objective: Increased regulatory requirements for sterilization in recent years have prompted a widespread transition from reusable to single-use laryngoscopes. The purpose of this study was to determine if the transition from metallic reusable to metallic single-use laryngoscopes impacted the performance of direct laryngoscopy at an academic medical center., Design: Single-site retrospective cohort study., Setting: General anesthetic cases requiring tracheal intubation., Patients: Adult patients undergoing non-emergent procedures., Interventions: Data were collected two years before and two years after a transition from metallic reusable to metallic single-use laryngoscopes., Measurements: The primary outcome was need for intubation rescue with an alternate device. Secondary outcomes were difficult laryngeal view (modified Cormack-Lehane grade ≥ 2b) and hypoxemia (SpO 2  < 90% for >30 s) during direct laryngoscopy intubations. Subgroup analyses for rapid sequence induction, Macintosh blades, Miller blades, and patients with difficult airway risk factors (Obstructive Sleep Apnea, Mallampati ≥3, Body Mass Index >30 kg/m 2 ) were performed., Main Results: In total, 72,672 patients were included: 35,549 (48.9%) in the reusable laryngoscope cohort and 37,123 (51.1%) in the single-use laryngoscope cohort. Compared with reusable laryngoscopes, single-use laryngoscopes were associated with fewer rescue intubations with an alternate device (covariates-adjusted odds ratio [OR] 0.81 95% CI 0.66-0.99). Single-use laryngoscopes were also associated with lower odds of difficult laryngeal view (OR 0.86; 95% CI 0.80-0.93). Single use laryngoscopes were not associated with hypoxemia during the intubation attempt (OR 1.03; 95% CI 0.88-1.20). Similar results were observed for subgroup analyses including rapid sequence induction, Macintosh blades, Miller blades, and patients with difficult airway risk factors., Conclusions: Metallic single-use laryngoscopes were associated with less need for rescue intubation with alternate devices and lower incidence of poor laryngeal view compared to reusable metallic laryngoscopes., Competing Interests: Declaration of Competing Interest None., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Background: During the COVID-19 pandemic, anesthesiologists were redeployed as transplant ICU intensivists and a postanesthesia care unit was converted to a novel transplant ICU. This study compared the outcomes of patients undergoing liver transplantation under the new model with the prepandemic model., Methods: Adult patients who underwent liver transplantation at an urban tertiary care center in the United States from December 28, 2015, through May 1, 2020, were identified and grouped according to date of procedure. Peri-COVID cases included transplants that were performed after March 3, 2020. Transplants performed before March 3, 2020, served as pre-COVID controls., Results: A total of 523 liver transplant patients (30 study cases, 493 controls) were included. Kaplan-Meier survival analysis showed no significant difference in novel transplant ICU length of stay (N-TLOS) (median LOS 3.8 vs. 4.5 days, log-rank p = 0.60) and hospital length of stay (HLOS) (median LOS 14.2 vs. 14.5 days, log-rank p = 0.66). Cox proportional hazards regression with inverse probability of treatment weighting showed no difference in N-TLOS (hazard ratio [HR] 0.91, 95% confidence interval [CI] 0.67-1.23, p = 0.55) or HLOS (HR 0.90, 95% CI 0.65-1.25, p = 0.52). In addition, there were no significant differences (pre-COVID vs. COVID) in time to extubation (median [interquartile range] 28.7 [20.6-50.7] vs. 26.8 [17.4-40.8] hours, p = 0.35), one-year patient survival (12.0% vs. 6.7%, p = 0.055), one-year graft survival (13.4% vs. 6.7%, p = 0.43), and readmission to the ICU (15.0% vs. 20.0%, p = 0.68)., Conclusion: Care provided by non-intensivist anesthesiologists to patients undergoing orthotopic liver transplantation during a pandemic emergency resulted in outcomes similar to those of care provided by intensivists., (Copyright © 2022 The Joint Commission. Published by Elsevier Inc. All rights reserved.)

Study Objective: To elucidate the association between delayed extubation, postoperative complications, and episode-based resource utilization., Design: Retrospective Propensity-Matched Cohort Study., Setting: Single Large Academic Medical Center., Patients: The computerized anesthetic records of 17,223 patients undergoing spine surgery from January 2006 through November 2016 were reviewed for this study. The records of 11,421 patients met inclusion criteria for final analysis, with 527 subjects who had delayed extubation following their procedure., Interventions: Delayed extubation, defined as patients not extubated prior to leaving the operating room., Measurements: Computerized anesthetic records of spine surgery patients were analyzed retrospectively. Corresponding Medicare Severity Diagnosis Related Group numbers (MS-DRGs) were then identified, as well as associated lengths of stay and costs of care. We compared hospital-acquired International Classification of Diseases-9 (ICD-9) and ICD-10 postoperative complication codes linked to each record to assess differences in outcome., Main Results: Increasing medical and surgical complexity is associated with delayed extubation. Using propensity score matching, delayed extubation was independently associated with a higher likelihood of any postoperative complication (Odds Ratio [OR]: 1.79; 95% Confidence Interval [CI]: 1.23-2.61); major complications (OR: 2.22; 95% CI: 1.31-3.76); prolonged length of hospital stay (Hazard Ratio [HR]: 0.82 (0.72, 0.95), p = 0.006); prolonged Intensive Care Unit (ICU) stay (HR: 0.68 (0.61, 0.76), p < 0.001); and were less likely to be discharged home (OR: 1.40 (1.02, 1.92), p = 0.036). Propensity score matching demonstrated that anesthesiologist handoff was not independently associated with any of the examined adverse outcomes., Conclusions: Delayed extubation after spine surgery was associated with a statistically significant increased incidence of postoperative complications as well as increased hospital episode-based resource utilization in the form of increased hospital length of stay, ICU length of stay, post-acute care at a facility, and higher cost of hospitalization. Although anesthesiologist handoff was associated with delayed extubation, it was not independently associated with postoperative complications when propensity score matching was applied., (Published by Elsevier Inc.)

Background: Intrathecal morphine is a popular and effective regional technique for pain control after open liver resection, but its delayed analgesic onset makes it less useful for the intraoperative period. The aim of this retrospective study was to compare the analgesic efficacy and other secondary benefits of the addition of hyperbaric bupivacaine to intrathecal morphine ± fentanyl. We hypothesized that bupivacaine could serve as an analgesic "bridge" prior to the onset of intrathecal morphine/fentanyl thereby lowering opioid consumption and enhancing recovery., Methods: Cumulative intraoperative and postoperative opioid consumption as well as other intra- and postoperative variables were collected and compared between groups receiving intrathecal morphine alone or intrathecal morphine ± hyperbaric bupivacaine., Results: Sixty-eight patients were selected for inclusion. Cumulative intraoperative morphine consumption was significantly reduced in the bupivacaine group while other intraoperative parameters such as intravenous fluids, blood loss, and vasopressors did not differ. There was a statistically significant improvement in time to first bowel movement in the experimental group., Discussion: The intraoperative opioid sparing effects and improved time to bowel function with the addition of hyperbaric bupivacaine to intrathecal morphine may make this technique an easy and low risk method of enhancing recovery after open liver resection., (Copyright © 2021 International Hepato-Pancreato-Biliary Association Inc. Published by Elsevier Ltd. All rights reserved.)

Objective: Older adults with type 2 diabetes (T2D) are at increased risk for depression, cognitive decline, and dementia compared to those without T2D. Little is known about the association of simultaneous changes in depression symptoms and cognitive decline over time., Methods: Subjects (n=1021; mean age 71.6 [SD=4.6]; 41.2% female) were initially cognitively normal participants of the Israel Diabetes and Cognitive Decline study who underwent evaluations of depression and cognition approximately every 18 months. Cognitive tests were summarized into four cognitive domains: episodic memory, attention/working memory, executive functions, and semantic categorization. The average of the z-scores of the four domains defined global cognition. Depression symptoms were assessed using the Geriatric Depression Scale, 15-item version. We fit a random coefficients model of changes in depression and in cognitive functions, adjusting for baseline sociodemographic and cardiovascular variables., Results: Higher number of depression symptoms at baseline was significantly associated with lower baseline cognitive scores in global cognition (estimate = -0.1175, SE = 0.021, DF = 1,014, t = -5.59; p < 0.001), executive functions (estimate = -0.186, SE = 0.036, DF = 1,013, t = -5.15; p = <0.001), semantic categorization (estimate = -0.155, SE = 0.029, DF = 1,008, t = -5.3; p < 0.001), and episodic memory (estimate = -0.08165, SE = 0.027, DF = 1,035, t = -2.92; p = 0.0036), but not with rate of decline in any cognitive domain. During follow-up, a larger increase in number of depression symptoms, was associated with worse cognitive outcomes in global cognition (estimate = -0.1053, SE = 0.027, DF = 1,612, t = -3.77; p = 0.0002), semantic categorization (estimate = -0.123, SE = 0.036, DF = 1,583, t = -3.36; p = 0.0008), and in episodic memory (estimate = -0.165, SE = 0.055, DF = 1,622, t = -3.02; p = 0.003), but the size of this effect was constant over time., Conclusion: In elderly with T2D, increase in depression symptoms over time is associated with parallel cognitive decline, indicating that the natural course of the two conditions progresses concurrently and suggesting common underlying mechanisms"., (Copyright © 2020 American Association for Geriatric Psychiatry. Published by Elsevier Inc. All rights reserved.)

Background: Cardiopulmonary resuscitation (CPR) requires effective chest compressions and ventilations to circulate and oxygenate blood. It has been established that a 2-handed mask seal is superior when providing bag-valve-mask (BVM) ventilations. However a 1-handed technique remains the standard with which health care providers are trained to perform 2-rescuer CPR., Objectives: We sought to determine if a modified 2-rescuer CPR technique that incorporates a 2-handed mask seal during ventilations can be accomplished without compromising chest compression quality during a simulated cardiac arrest., Methods: Medical student volunteers were divided into an "intervention" arm, with 1 rescuer creating a 2-handed mask seal and the second rescuer performing chest compressions followed by that second rescuer squeezing the BVM bag to deliver ventilations during compression pauses, and a "control" arm, in which standard 2-rescuer CPR was performed. Both arms received a brief CPR refresher following a standard script. The 2 rescuer teams then performed 2 rounds of CPR on a manikin while being video recorded. Data were collected from real-time evaluation and post hoc video analysis., Results: Forty-seven pairs of students enrolled in the study. There were no statistically significant differences between the intervention and control arms for median (interquartile range [IQR]) compression fraction (72% [69.5-75.7%] vs. 73.2% [69.1-76.1%]; p = 1.0), median time to complete 2 rounds of CPR (207.8 s [198.5-222.9 s] vs. 214.7 s [201.3-219.5 s]; p = 0.625), median hands-off time (49.8 s [46.2-63.0 s] vs. 55.4 s [50.4-65.2 s]; p = 0.278), or median time for 30 compressions (15.2 s [14.3-15.9 s] vs. 15.4 s [14.6-16.3 s]; p = 0.452)., Conclusion: Two-rescuer CPR incorporating a 2-handed face mask seal can be performed effectively without impacting chest compression quality during simulated cardiac arrest., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background: Few perioperative studies have assessed subjective cognitive complaint (SCC) in combination with neuropsychological testing. New nomenclature guidelines require both SCC and objective decline on cognitive testing. The objective of our study was to compare SCC and neuropsychological testing in an elderly surgical cohort., Methods: This was a secondary analysis of a prospective cohort trial at a single urban medical centre. We included patients older than 65 yr, undergoing major non-cardiac surgery with general anaesthesia. Those with dementia or inability to consent were excluded, as were those undergoing emergency, cardiac, or intracranial procedures. Patients completed a neuropsychiatry battery before and 3 months after surgery. SCC was defined utilising the single question: 'do you feel that surgery and anaesthesia have impacted your clarity of thought?' Objective cognitive decline was defined as 1 standard deviation decline from the baseline of the cohort., Results: Of the 120 patients who completed assessments, 16/120 (13%) had SCC after surgery, and 41/120 (34%) had objective decline. The sensitivity of SCC in relation to objective decline was 24% and specificity was 92%. Of the patients with SCC, 43.8% were screened positive for depression after surgery compared with 4.9% without SCC; P=0.001., Conclusions: Many patients with objective cognitive decline did not report SCC. There appears to be a relationship between SCC and depression. The use of SCC in surgical patients to define postoperative neurocognitive disorders needs to be better delineated., Clinical Trial Registration: NCT02650687., (Copyright © 2019 British Journal of Anaesthesia. Published by Elsevier Ltd. All rights reserved.)

Purpose: MRI-negative epilepsy patients could benefit from advanced imaging techniques such as high-resolution diffusion magnetic resonance imaging (dMRI). Our aim was to perform hippocampal subfield-specific tractography and quantify connectivity of the subfields in MRI-negative patients. Abnormal connectivity of the hippocampal subfields may help inform seizure focus hypothesis and provide information to guide surgical intervention., Methods: Hippocampal structural imaging and dMRI was acquired in 25 drug resistant MRI-negative patients and 25 healthy volunteers. The hippocampi of each subject was segmented on high-resolution structural images and dMRI-based probabilistic tractography was performed in each subfield. The degrees of connectivity and fiber densities of the hippocampal subfields were quantified and compared between epilepsy patients and healthy volunteers., Results: We were able to perform subfield-specific hippocampal tractography in each subject that participated in this study. These methods identified some hippocampal subfields that are abnormally connected in MRI-negative patients. In particular patients suspected of left temporal seizure focus exhibited increased connectivity of certain ipsilateral subfields, especially the subiculum, presubiculum, and parasubiculum, and reduced connectivity of some contralateral subfields, such as CA1 and subiculum., Conclusions: Our data suggest that the hippocampal subfields are connected in distinct ways in different types of epilepsy. These results may provide important information that could help inform seizure focus hypothesis and in the surgical treatment of MRI-negative patients. These observations suggest that high-resolution dMRI-based tractography of the hippocampal subfields can detect subtle abnormalities in otherwise normal-appearing MRI-negative patients., (Copyright © 2018 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.)

Objective: The American Society of Anesthesiologists physical status (ASA-PS) is associated with increased morbidity and mortality in the perioperative period. When surgeries are scheduled by surgeons and their staff at our large institution a presumed ASA-PS is chosen. This is because our institution (and, anecdotally, others in our hospital system and elsewhere), recognizing the relationship between higher ASA-PS and poorer postoperative outcomes, requires all patients with higher ASA-PS levels (≥3) to undergo enhanced preoperative workup. The patients may not, however, necessarily be seen in the anesthesia clinic prior to surgery. As a result, patients are assigned a presumed ASA-PS by a non-anesthesia provider (e.g., surgeons and physician extenders) that may not reflect the ASA-PS chosen by the anesthesiologist on the day of surgery. Errors in the accuracy of the ASA-PS prior to surgery lead to unnecessary and costly preoperative testing, delays in operative procedures, and potential case cancellations. Our study aimed to determine whether there are significant differences in the assignment of ASA-PS by non-anesthesia providers when compared to anesthesia providers., Design: We administered an IRB-approved survey asking the ASA-PS of 20 hypothetical case vignettes to 229 clinicians in various departments. Responses by non-anesthesia providers were compared to the consensus of the department of anesthesiology., Setting: Faculty office spaces and conferences., Patients: No patients, physicians only., Interventions: Survey administration., Measurements: ASA-PS scores acquired from surveys., Main Results: Residents and faculty in the department of anesthesiology demonstrated no statistical difference in the median ASA score in 19/20 case scenarios. All other departments were statistically different when compared to the department of anesthesiology (p<0.05). The probability of a department either over- or under-rating the ASA-PS was calculated, and is summarized in Fig. 3. All departments, except anesthesiology, had a 30-40% chance of under-rating the ASA-PS of the patients in the clinical vignettes., Conclusions: Non-anesthesia providers assign ASA-PS with significantly less accuracy than do anesthesia providers, even when adjusted for multiple comparisons. Surgical and procedural departments were found to consistently under-rate the ASA-PS of patients in our clinical vignettes., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Objectives: This study sought to identify possible anatomic predictors of acute type B aortic dissection (AAD) in hypertensive patients using multidetector computed tomography angiography (CTA)., Background: Although hypertension remains one of the most significant risk factors for AAD development, it is unlikely to be the only risk factor for AAD. Few studies have assessed anatomical predictors of AAD development., Methods: CTA of normotensive patients without AAD (group 1, n = 35), hypertensive patients without AAD (group 2, n = 37), and hypertensive patients with AAD (group 3, n = 37) were compared. The length, diameter, volume, and tortuosity of the aorta as well as arch vessel angulation were measured for each patient and normalized to group 1 averages. Stepwise logistic regression identified significant anatomical associations; the model was validated based on 1,000 bootstrapped samples., Results: The demographics of the groups were similar. The length of the proximal and entire aorta, the diameters in the proximal ascending aorta and aortic arch, and the aortic volumes were all greater (p < 0.0001, p = 0.0064 for ascending aortic diameter) in group 3 than in groups 1 and 2, as was entire aortic tortuosity (p < 0.0001). An AAD risk model was developed based on aortic arch diameter, length from the aortic root to the iliac bifurcation, and angulation of the brachiocephalic artery origin from the aorta. The bootstrap estimate of the area under the receiver operating curve was 0.974., Conclusions: Enlargement of the ascending aorta and aortic arch and increased aortic tortuosity reflect an aortopathy which enhances the probability of AAD. A model based on 3 anatomical variables demonstrates significant associations with AAD: it may allow identification by aortic imaging of the hypertensive patient most at risk, and permit implementation of aggressive medical management and consideration of pre-emptive surgery to prevent dissection., (Copyright © 2013 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Background: The best option for repair of descending thoracic and thoracoabdominal aortic aneurysms (TAAA)-whether open operation or stent grafting-is increasingly a subject of controversy. We examined the results of open surgical repair in patients aged 60 years or younger to assess the value of conventional repair in younger patients., Methods: From October 2002 to October 2010, 107 of 294 TAAA operations were in patients (75 men [70%]) aged a mean of 48 ± 9 years. Twelve patients (11%) had Marfan syndrome. Operations were elective in 101 (94%); previous aortic operations had been performed in 40 (37%). The most common indication for operation was chronic dissection, in 60 (56%); 5 (4.7%) had acute dissection, and rupture was present in 6 (5.6%). Descending repair was undertaken in 44 (41%), in 32 (73%) as an elephant trunk stage II. Deep hypothermic circulatory arrest was used in 46 (42.9%). Neurologic monitoring and cerebrospinal fluid drainage were routine. Median postoperative follow-up was 4.3 years (range, 2 days to 7.9 years)., Results: Overall 30-day mortality was 4.7%. Stroke occurred in 4 patients (3.7%) and paraplegia in 1 (0.9%). The linearized rate for reoperation for TAAA was 0.22/100 patient-years (1 patient in 448.8 patient-years). Survival at 1, 5, and 8 years was 90.5%, 89.4% and 80.5%, respectively. During follow-up, 1 patient with Ehlers-Danlos died of aortic complications at 4.5 years., Conclusions: Although direct comparison with stent grafting is limited by the diversity of patients and indications in published reports, our results suggest that open repair should be the modality of choice. Early mortality and neurologic complication rates are similar, if not superior, to endovascular repair for descending aortic and TAAAs. Open repair has proven durability and a very low rate of required reintervention, in contrast with endovascular repair., (Copyright © 2013 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: We undertook a retrospective study of the pattern of reoperations in surgical patients with Marfan disease., Methods: Between 1985 and 2008, 83 Marfan patients (60 males, 23 females) underwent 155 aortic operations in our institution. Twenty-eight patients had acute dissection (22 type A, 6 type B), and two had aortic rupture. Mean age at initial operation was 32±13 years. Operations included valve-sparing or Bentall aortic root repair, and ascending aorta, arch, descending thoracic, thoracoabdominal aorta, and infrarenal aortic replacement. Sixty-one patients whose initial operation was elective (Group I) were compared with 22 patients with initial emergency surgery (Group II)., Results: Overall, 81/83 patients ultimately underwent root/ascending repair: 64% initially and 36% at reoperation. Operative mortality in Group I was 1.6% for both initial operations and reoperations vs 9.0% and 0% in Group II. Significant differences between Group I and Group II patients included: total reoperations (1 vs 3, p=0.05); arch operations (0 vs 1, p=0.003); descending thoracic aortic operations (0 vs 0.5, p=0.003); and total aortic segments replaced (1.6±1.0 vs 2.4±1.1, p=0.001). Survival at 5 and 10 years did not differ between Group I and II patients (87% and 71% vs 82% and 56%, p=0.19)., Conclusions: Although reoperation occurs in about half of surgical Marfan patients, reoperative mortality is low. Patients with initial elective procedures fare better than those with initial emergency surgery: they have fewer subsequent operations, fewer aortic segments replaced, and trend toward improved survival. Elective root replacement should be seriously considered in any Marfan patient with significant root dilatation., (Copyright © 2012 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Endovascular repair of descending thoracic and thoracoabdominal aortic aneurysms is an appealing alternative to the standard surgical approach, but precludes revascularization of segmental arteries (SAs). For safer surgical and endovascular repairs, an accurate prediction of the risk of paraplegia in relation to the extent of SA sacrifice is needed., Methods: From January 1994 to October 2008, 609 patients (mean age, 63 ± 14 years) underwent surgical descending thoracic or thoracoabdominal aortic aneurysm repair without SA reimplantation. Three hundred seventy-six patients (62%) were male; 159 (26%) had urgent or emergent operation; 199 (33%) had previous aortic surgery. Somatosensory- or motor-evoked potential monitoring and cerebrospinal fluid drainage were routinely performed., Results: Hospital mortality was 10.7% (65 patients). Spinal cord injury (SCI) occurred in 3.4% (21 patients). The extent of resection-expressed as the number of SAs sacrificed (p = 0.007)-and the need for visceral artery reimplantation (p = 0.03) were independent risk factors for paraplegia. Further analysis identified four risk groups (p < 0.0001): fewer than 8 SAs sacrificed (group A, SCI = 1.2%); sacrifice of 8 to 12 SAs with proximal origin in the upper thorax (group B, SCI = 3.7%); 8 to 12 SAs sacrificed beginning in the lower thorax (group C, SCI = 15.4%); and 13 or more SAs sacrificed (group D, SCI = 12.5%). This four-group model more accurately predicts SCI risk than the Crawford classification (goodness of fit c statistic: 0.748 versus 0.640)., Conclusions: The extent of SA sacrifice is the most powerful predictor of paraplegia risk. For aneurysms of moderate extent, a more distal location involving the abdominal aorta increases the risk of spinal cord injury. Sacrifice of fewer than 8 SAs is associated with a very low paraplegia risk regardless of location., (Copyright © 2010 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

In Asia, limited literature has been published on the association between daily mortality and ambient air pollution. We examined the associations of daily cause-specific mortality with daily mean concentrations of particulate matter (PM) with a mass median aerodynamic diameter less than 10 microm (PM(10)) in Wuhan, China using 4 years of data (2001-2004). There are approximately 4.5 million residents in Wuhan who live in the city core area of 201 km(2) where air pollution levels are higher and pollution ranges are wider than the majority of cities in the published literature. We use quasi-likelihood estimation within the context of the generalized additive models (GAMs) (natural spline (NS) models in R) to model the natural logarithm of the expected daily death counts as a function of the predictor variables. We found consistent PM(10) effects on mortality with the strongest effects on lag 0 day. Every 10 microg/m(3) increase in PM(10) daily concentration at lag 0 day was significantly associated with an increase in non-accidental (0.36%; 95% CI 0.19-0.53%), cardiovascular (0.51%; 95% CI 0.28-0.75%), stroke (0.44%; 95% CI 0.16-0.72%), cardiac (0.49%; 95% CI 0.08-0.89%), respiratory (0.71%; 95% CI 0.20-1.23%), and cardiopulmonary (0.46%; 95% CI 0.23-0.69%). In general, these effects were stronger among the elderly (65 years > or = 45 years) than among the young. The exploration of exposure-response relationships between PM(10) and cause-specific mortality suggests the appropriateness of assuming linear relationships, where the PM(10) concentration in Wuhan ranged from 24.8 to 477.8 microg/m(3). We conclude that there is consistent evidence of acute effects of PM(10) on cardiopulmonary mortality. A linear no threshold exposure-response relationship is suggested between PM(10) and the studied cause-specific mortality.

Objective: To investigate whether age-related macular degeneration (AMD) is associated with the development of myocardial infarction (MI) among elderly Americans., Design: Population-based cross-sectional and cohort study., Participants: Five percent random sample of 2000 to 2003 Medicare enrollees., Methods: The cross-sectional study included the first 2-year (2000 and 2001) enrollees who were aged > or =65 years (n = 1,519,086). The cohort study included only baseline MI-free enrollees (n = 1445677)., Main Outcome Measures: Chronic conditions (AMD and type, history of MI, hypertension, and diabetes) were defined based on any occurrence of relevant International Classification of Diseases 9 codes in relevant diagnosis fields of the baseline Medicare claim files. A total of 56611 incident MI cases were identified from the follow-up data (2002 and 2003)., Results: Baseline mean age was 76 years, with 60% women and 88% whites. The prevalence of neovascular AMD was 2.2% (2.3% in women vs. 1.7% in men and 2.3% in whites vs. 1.2% in blacks; P<0.01 for both gender and race differences). The prevalence of nonneovascular AMD was 8.8% (9.9% in women vs. 7.3% in men and 9.5% in whites vs. 4.3% in blacks; P<0.01 for both gender and race differences). Baseline age-, gender-, and race-adjusted prevalences of hypertension, diabetes, and history of MI were 75%, 33%, and 5.00%, respectively, in the neovascular AMD group. In contrast, they were 73%, 27%, and 4.68% in the nonneovascular AMD group, and 65%, 25%, and 4.54% in the non-AMD group (P<0.01 for comparing the prevalence in neovascular and nonneovascular AMD vs. non-AMD groups). Prospectively, baseline age-, gender-, race-, hypertension-, and diabetes-adjusted 2-year incident odds ratios and 95% confidence intervals of MI associated with AMD are 1.19 (1.16-1.22) for all persons with AMD, 1.26 (1.20-1.33) for neovascular AMD, and 1.18 (1.14-1.21) for nonneovascular AMD., Conclusions: AMD is associated with older age, female gender, being white, and having a history of MI, hypertension, and diabetes. Furthermore, presence of AMD, especially neovascular AMD, is prospectively associated with a higher risk of incident MI. These findings, if confirmed by other studies that control for smoking and other lifestyle covariables, suggest the possibility of shared common antecedents between MI and AMD.

We raise the concern of whether the use of a placebo group in a randomized clinical trial is sufficient to eliminate bias in the assessment of the effectiveness of a drug when enrollment into the trial prior to intervention requires diagnosis of a dichotomous disease, and the diagnostic test is subject to uncertainty. Due to misclassification and the regression effect, the observed difference in the proportions of diseased individuals between the treatment and placebo groups at follow-up will be equal to the true difference multiplied by the positive predictive value at screening and the difference between the sensitivity and the false-positive value at follow-up. Thus, measurement error of disease status before and after administering the intervention attenuates the intervention effect. Validation data corresponding to both the screening and follow-up conditions are necessary to provide additional information on the validity of the diagnostic test. Proper statistical analysis should include such data for an accurate portrayal of the effectiveness of the treatment., (Copyright 2002 Elsevier Science Inc.)