Role of cytomegalovirus infection after kidney transplantation on the subsequent risk of atherosclerotic and thrombotic events

Background and aims: Whether cytomegalovirus (CMV) infection increases the risk of cardiovascular complications after kidney transplantation (KT) through different indirect effects remains controversial. Methods: We analyzed the incidence of post-transplant atherosclerotic (PAEs) and thrombotic events (PTEs) in 465 KT recipients according to the previous exposure to any level or high-level (≥1,000 IU/mL) CMV viremia (either asymptomatic or clinical disease) by means of landmark analysis beyond days 30, 180 and 360 after transplantation. Proportional hazards models were constructed with death and graft loss as competing risks. Results: After a median of 722 days, the cumulative incidences of PAE and PTE were 6.0% each. Most PAEs (53.6%) occurred beyond post-transplant day 360, whereas most PTEs (60.7%) were diagnosed between days 30–180.The incidence of PAE beyond day 180 was higher among patients with previous CMV viremia compared to those without (two-year rates: 4.7% versus 0.4%; P-value = 0.035). This difference was more pronounced in recipients developing high-level viremia (6.3% versus 0.7%, respectively; P-value = 0.013). After multivariate adjustment for age, pre-transplant cardiovascular risk, antiplatelet and statin therapy and graft function, however, associations were not maintained either for any-level (hazard ratio [HR]: 1.84; 95% confidence interval [CI]: 0.48–7.05) or high-level CMV viremia (HR: 2.84; 95% CI: 0.78–10.36). No significant differences were found in the remaining landmark analyses (days 30 or 360) or for the outcome of PTE either. Conclusions: Our study does not support that CMV infection independently contributes to the risk of PAE or PTE after KT.