Associations of serum 25-hydroxyvitamin D and vitamin D receptor polymorphisms with risks of cardiovascular disease and mortality among patients with chronic kidney disease: a prospective study

Background: Evidence regarding the relationships of serum 25-hydroxyvitamin D [25(OH)D] with cardiovascular diseases (CVD) and mortality among patients with chronic kidney disease (CKD) is limited and inconsistent. Objectives: This study aimed to investigate the associations between serum 25(OH)D and CVD incidence and mortality among patients with CKD. Methods: This prospective study included 21,507 participants with CKD and free of CVD in the UK Biobank. Incidences of total and subtypes of CVD and mortality were ascertained via electronic health records. Cox proportional hazard regression models were used to estimate the hazard ratios (HRs) and 95% confidential intervals (CIs) for CVD incidence and mortality. Results: The median serum 25(OH)D concentration was 44.0 nmol/L (interquartile range: 30.1, 60.6 nmol/L). After multivariable adjustment, compared with CKD patients with serum 25(OH)D concentrations of < 25 nmol/L, those with serum 25(OH)D >= 75 nmol/L had HRs (95% CIs) of 0.80 (0.71, 0.90) for total CVD incidence, 0.82 (0.69, 0.97) for ischemic heart disease, 0.56 (0.41, 0.77) for stroke, 0.64 (0.46, 0.88) for myocardial infarction, 0.62 (0.49, 0.80) for heart failure, 0.60 (0.43, 0.85) for CVD mortality, and 0.62 (0.52, 0.74) for all-cause mortality. In addition, these associations were not modified by vitamin D receptor polymorphisms, with no significant interaction detected. Conclusions: Higher serum 25(OH)D concentrations were significantly associated with lower risks of total and subtypes of CVD incidence and mortality among individuals with CKD. These fi ndings highlight the importance of maintaining adequate vitamin D status in the prevention of CVD and mortality in patients with CKD.