The impact of new onset diabetes on cardiovascular risks in orthotopic liver transplant recipients: findings from the COLT study

Background: Orthotopic liver transplantation (OLT) has greatly improved short-term survival for end-stage liver disease. However, cardiovascular events (CVE) still pose a significant threat to long-term post-transplant health. Aim of this study is to assess the occurrence of long-term cardiovascular events and whether it relates to new-onset diabetes after liver transplantation (NODALT). Methods: We conducted a multicentric retrospective analysis of adult OLT recipients with regular follow-up visits spanning from January 1995 to December 2020. Data collection included anamnestic, clinical, anthropometric, and laboratory data from two centers. NODALT was diagnosed following ADA guidelines. The primary outcome was incident CVE (a composite of fatal and non-fatal stroke and myocardial infarction). CVE occurrence was analyzed in relation to NODALT diagnosis, along with clinical characteristics associated with its development. Results: Ninety-three eligible Caucasian patients, with a median age of 57.0 years (IQR: 49.0–62.0, 69.9% male), were enrolled. Over the median follow-up period of 100.5 months, 29 patients (31.2%) developed NODALT, and 14 patients (15.1%) developed any CVE, with 9 being in the NODALT group. A significant association between NODALT and cardiovascular complications was confirmed by both generalized estimating equation (OR 5.31; 95% CI 1.59–17.72, p = 0.006) and Kaplan–Meier analysis (log-rank = 0.046). Metabolic syndrome and impaired fasting glucose were identified as baseline risk factors for the incident NODALT (OR 5.75; 95% CI 1.44–22.92, p = 0.013 and OR 7.29; 95% CI 1.46–36.41, p = 0.015, respectively). Conclusions: Post-OLT cardiovascular events are less frequent than previously reported but are notably linked to NODALT, highlighting the interplay between metabolic syndrome and impaired fasting glucose. Graphical Abstract: (Figure presented.)