Introduction: The aims of this study were to quantify the incidence of cardiovascular events and identify the clinical relevance of modifiable variables.
Materials and methods: The 1729 patients who underwent renal transplantation from 1981 to 2004 were evaluated in an observational, prospective follow-up study with no exclusions. A cardiovascular event was defined as the presence of ischemic cardiac disease (chest pain-myocardial infarction), cardiac insufficiency, arrhythmia (auricular fibrillation), peripheral vascular disease, or cerebrovascular accident. A survival analysis was performed using the Kaplan-Meier method. A Cox regression analysis was applied. Having identified the predictive variables of cardiovascular events, the population attributable fraction (PAF) and the etiological fraction (EF) were estimated. A risk score was calculated using Cox regression coefficients.
Results: The accumulated incidence of cardiovascular events was 22.2%, with an incidence rate of 468.6 x 10,000 follow-up years. From the Cox regression model, the variables with an independent effect close to statistical significance to predict cardiovascular events were as follows: recipient age (RR = 1.05), smoking at the time of the transplantation (RR = 2.1), left ventricle hypertrophy during follow-up (RR = 2.4), prior diabetes mellitus, and obesity (body mass index >or=30). At the time of transplantation, 41.7% were smokers. During follow-up, a clear difference was observed in the incidence rates of cardiovascular events between smokers and nonsmokers. Similar phenomena were observed for left ventricle hypertrophy and obesity. The resulting scores ranged between 0 and 5. The area under the ROC curve of the score for the prediction of cardiovascular events was 0.74.
Conclusion: The incidence of cardiovascular events was consistent with the literature. A series of modifiable variables of major clinical relevance exist to decrease the frequency of cardiovascular events following renal transplantation.