Associations of Serum 25(OH)D With Risk of Recurrent Cardiovascular Events in Individuals With Coronary Heart Disease

Abstract

Context: Few studies have examined the relationship between vitamin D and the risk of recurrent cardiovascular (CV) events in people with coronary heart disease (CHD).

Objective: This study aimed to investigate the associations of serum 25-hydroxyvitamin D (25(OH)D) concentration and the vitamin D receptor (VDR) polymorphisms with the risk of recurrent CV events in individuals with established CHD.

Methods: A total of 22 571 participants with CHD were included from the UK Biobank. Recurrent CV events, including myocardial infarction (MI), heart failure (HF), stroke, and CV disease mortality, were identified from electronic health records. Cox proportional-hazard models were used to calculate hazard ratios (HRs) and 95% CIs.

Results: The median (interquartile range) of serum 25(OH)D concentration was 44.8 nmol/L (range, 30.3-61.4 nmol/L), and 58.6% of participants had 25(OH)D below 50 nmol/L. During a median follow-up of 11.2 years, a total of 3998 recurrent CV events were documented. After multivariable adjustment, there was a nonlinear inverse relationship between serum 25(OH)D and recurrent CV events (P nonlinearity <.01), and the decreasing risk gradually leveled off at around 50 nmol/L. Compared with participants with serum 25(OH)D less than 25.0 nmol/L, the HRs (95% CIs) for participants with serum 25(OH)D of 50.0 to 74.9 nmol/L were 0.64 (0.58-0.71) for recurrent CV events, 0.78 (0.65-0.94) for MI, 0.66 (0.57-0.76) for HF, and 0.66 (0.52-0.84) for stroke. In addition, these associations were not modified by genetic variants in the VDR.

Conclusion: In people with established CHD, higher serum 25(OH)D concentrations were nonlinearly associated with a lower risk of recurrent CV events, with a potential threshold around 50 nmol/L. These findings highlight the importance of maintaining adequate vitamin D status in the prevention of recurrent CV events among individuals with CHD.

Keywords: cohort study; coronary heart disease; recurrent cardiovascular events; vitamin D.