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Abstract. The prognostic utility of myocardial perfusion studies (MPS) such as thallium scintigraphy and dobutamine stress echocardiography (DSE) for stratifying cardiac risk among candidates for kidney or kidney-pancreas transplantation is uncertain. This study is a meta-analysis to determine the prognostic significance of MPS results on future myocardial infarction (MI) and cardiac death (CD) in patients with end-stage renal disease (ESRD) assessed for kidney or kidney-pancreas transplantation. MEDLINE was searched using combinations of MeSH headings and text words for transplantation, coronary artery disease, prognosis, end-stage renal disease, and noninvasive cardiac testing (nuclear scintigraphy and DSE) for primary studies. Studies were included if they reported MPS results and cardiac events in patients assessed for kidney or kidney-pancreas transplantation. Methodologic study quality and outcome data were independently abstracted in duplicate by two researchers. The relative risks (RR) of MI and CD were calculated using a random effects model. Twelve articles met all inclusion criteria; 12 studies reported CD, and 9 reported MI. In eight studies, thallium scintigraphy was used (four with pharmacologic stress, four with exercise stress), whereas four used DSE. When compared with negative tests, positive tests had a significantly increased RR of MI (2.73 [95% CI, 1.25 to 5.97]; P ϭ 0.01) and CD (2.92 [95% CI, 1.66 to 5.12]; P Ͻ 0.001). Subgroup analyses of studies of diabetic patients indicated that positive tests were associated with a RR of CD 3.95 (95% CI, 1.48 to 10.5; P ϭ 0.006) and a RR of MI 2.68 (95% CI, 0.95 to 7.57; P ϭ 0.06) when compared with negative tests. In studies evaluating mixed populations of diabetic and nondiabetic patients, positive tests were associated with a RR of CD 2.52 (95% CI, 1.25 to 5.08; P ϭ 0.01) and with a RR of MI 2.79 (95% CI, 0.85 to 9.21; P ϭ 0.09) when compared with a negative test. The presence of reversible defects was associated with an increased risk of MI in diabetic patients and of CD in both subgroups; fixed defects were associated with an increased risk of CD but not MI. It is concluded that positive MPS are useful in identifying patients with significantly increased risk of future MI and CD in both diabetic and nondiabetic ESRD patients. Cardiovascular disease is common in individuals with endstage renal disease (ESRD) and accounts for between 40 and 45% of all deaths in these patients (1,2). At the time of initiation of chronic dialysis treatment in 1999, approximately 25% of patients have a history of ischemic heart disease and about 10% have had myocardial infarction (MI) (2,3). Although the rate of death from cardiac disease in ESRD patients in the United States fell in the 8-yr period between 1991 and 1998, the incident rate of MI rose in the second and third years of treatment by 15.7% and 6.8%, respectively (4). In addition, the short-term and long-term prognosis after acute MI in ESRD patients is poor, with 40% of patients dying of cardiac causes at ...

Abstract. In population-based studies, renal transplantation has been shown to improve survival compared to dialysis patients awaiting transplantation in the United States. However, dialysis mortality in the United States is higher than in Canada. Whether transplantation offers a survival advantage in regions where dialysis survival is superior to that in the United States is uncertain. This study examines a cohort of 1156 patients who started end-stage renal disease (ESRD) therapy and were wait-listed for cadaveric renal transplantation in the province of Ontario, Canada between January 1, 1990 and December 31, 1994. Patients were followed from wait-listing for renal transplant (n = 1156), to cadaveric first renal transplant (n = 722), to death, or to study end (December 31, 1995). The annual crude mortality rates for wait-listed dialysis patients and transplanted patients were 5.0 and 3.4%, respectively. In Cox proportional hazards models, mortality in wait-listed patients was associated with increased age and diabetes, but not time from onset of ESRD to wait-listing. Factors associated with death following transplantation include older age, diabetes, and longer time spent on the waiting list before transplantation. In a time-dependent Cox regression model, the relative risk of death after transplantation compared to dialysis varied in a time-dependent manner. Covariates associated with increased risk included older age, diabetes, and time from onset of ESRD to wait-listing. The average relative risk (RR) of dying was 2.91 (95% confidence interval [CI], 1.34 to 6.32) in the first 30 d after transplantation, but was significantly lower 1 yr after transplantation (RR 0.25; 95% CI, 0.14 to 0.42), indicating a beneficial long-term effect when compared to wait-listed dialysis patients. This long-term benefit was most evident in subgroups of patients with diabetes (RR 0.38; 95% CI, 0.17 to 0.87) and glomerulonephritis (RR 0.13; 95% CI, 0.04 to 0.39) as the cause of ESRD. The survival advantage associated with renal transplantation is evident in this cohort of patients with a lower wait-listed dialysis mortality than that reported previously in the United States. The magnitude of the treatment effect is consistent across studies.