Pre-transplant cardiovascular risks and adverse outcomes in patients after receiving kidney transplantation

Kidney transplantation (KT) has been reported to significantly improve the survival rate of patients with end-stage renal disease, but the long-term risk for major adverse cardiovascular and cerebrovascular events (MACCE) or mortality remains uncertain. Our study aimed to evaluate the association between cardiovascular risk factors and adverse outcomes in patients after KT. Using raw data from the National Health Insurance Research Database in Taiwan, we included 3,562 adult patients (1997–2013) who underwent uncomplicated KT. The median follow-up was 7.7 years (IQR 4.8–10.6), with a total of 28,267 person-years. Patients were censored at the date of the primary event, death, or December 31, 2013, whichever occurred first. We evaluated adverse outcomes, including non-fatal acute myocardial infarction (AMI), non-fatal stroke, and/or all-cause death, as primary events during the observation period (up to 17 years). The association of cardiovascular risk factors before KT was assessed using multivariate Cox proportional hazards models, adjusted for age, sex, and other available baseline factors. We also performed Kaplan–Meier analysis to estimate the cumulative risk. Among these patients, 225 (6.3%) were aged over 60 years, and 1,895 (53.2%) were male. All-cause death occurred in 703 patients (19.7%), non-fatal AMI in 125 (3.5%), and non-fatal stroke in 104 (2.9%). Only 853 patients (23.9%) had a waiting time for KT of < 1 year. Logistic regression analysis showed that only diabetes (OR = 2.085, 95% CI: 1.749–2.484, P < 0.001), AMI (OR = 2.568, 95% CI: 1.621–4.070, P < 0.001), and stroke before KT (OR = 4.376, 95% CI: 2.720–7.041, P < 0.001) were significantly associated with primary events, whereas hypertension and dyslipidemia were not. Consistently, the fully adjusted Cox model showed that diabetes (HR = 1.560, 95% CI: 1.338–1.819, P < 0.001), AMI (HR = 1.692, 95% CI: 1.188–2.410, P = 0.004), and stroke before KT (HR = 2.226, 95% CI: 1.612–3.074, P < 0.001) were independently associated with the composite primary event. Pre-transplant diabetes, AMI, and stroke were associated with increased risks of MACCE and all-cause mortality after KT. These findings support preoperative cardiovascular risk stratification in KT candidates.