Vitamin D status and risk of infections after liver transplantation in the Swiss Transplant Cohort Study

Abstract

MAIN PROBLEM Increasing evidence indicates a role of vitamin D in the immune system affecting response to infections. We aimed to characterize the role of vitamin D status, i.e. deficiency (25-OH vitamin D [25-OHD] < 50nmol/l) and no deficiency (25-OHD ≥ 50nmol/l) in incident infections after liver transplantation. METHODS In 135 liver transplant recipients blood samples drawn at time of liver transplantation and 6 months afterwards were used to determine 25-OHD levels. Incident infections episodes were prospectively collected within the STCS database. Poisson regression was applied to address associations between vitamin D status and incident infections. RESULTS Vitamin D deficiency was common at time of transplantation and 6 months afterwards without a significant change in median 25-OHD levels. In univariable analyses vitamin D deficiency was a risk factor for incident infections in the first 6 months post-transplant (IRR 1.52, 95% CI 1.08-2.15, P=0.018) and for bacterial infections occurring after 6 up to 30 months post-transplant (IRR 2.29, 95% CI 1.06-4.94, P=0.034). These associations were not detectable in multivariable analysis with adjustment for multiple confounders. CONCLUSIONS Efforts to optimize vitamin D supplementation in liver transplant recipients are needed. Our data question the role of vitamin D deficiency in incident infections.