Traditional risk factors do not adequately explain coronary heart disease (CHD) risk after kidney transplantation. We used a large, multicenter database to compare traditional and nontraditional CHD risk factors, and to develop risk-prediction equations for kidney transplant patients in standard clinical practice. We retrospectively assessed risk factors for CHD (acute myocardial infarction, coronary artery revascularization or sudden death) in 23 575 adult kidney transplant patients from 14 transplant centers worldwide. The CHD cumulative incidence was 3.1%, 5.2% and 7.6%, at 1, 3 and 5 years posttransplant, respectively. In separate Cox proportional hazards analyses of CHD in the first posttransplant year (predicted at time of transplant), and predicted within 3 years after a clinic visit occurring in posttransplant years 1-5, important risk factors included pretransplant diabetes, new onset posttransplant diabetes, prior pre-and posttransplant cardiovascular disease events, estimated glomerular filtration rate, delayed graft function, acute rejection, age, sex, race and duration of pretransplant end-stage kidney disease. The risk-prediction equations performed well, with the time-dependent c-statistic greater than 0.75. Traditional risk factors (e.g. hypertension, dyslipidemia and cigarette smoking) added little additional predictive value. Thus, transplant-related risk factors, particularly those linked to graft function, explain much of the variation in CHD after kidney transplantation. (4,5), and several nontraditional risk factors are reported to be associated with CHD after kidney transplantation (2,4,(6)(7)(8)(9)(10)(11)(12)
Materials and Methods
the discriminatory ability of the prediction model was not significantly improved by adding these Framingham risk factors and the prediction model performed much better than the Framingham Heart Study equation (Figure 2). We also examined CHD risk in the subset of patients from the 7 (of 14)
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American Journal of Transplantation 2010; 10: 338-353Predicting Posttransplant CHD
Figure 1: Predicted probability of coronary heart disease (dark line) with 95% confidence interval (lighter lines), and distribution of risk scores in the Patient Outcomes after Renal Transplant population (bars). (Panel A) Prediction of coronary heart disease in the first year posttransplant from variables available at the time of transplant (Table 1). (Panel B) Prediction of coronary heart disease in the first year posttransplant from variables available at the time of transplant and during the first week after transplant (Table 2). (Panel C) Prediction of coronary heart disease within 3 years after a visit occurring 1-5 years posttransplant (Table 3). study centers that routinely collected information on smoking status at the time of transplant (n = 9785 with 361 CHD events; Table A.4). Smoking status did not independently predict CHD, significantly affect which variables predicted CHD events, or affect the discriminatory ability of the prediction model (data not shown). Smokers were...