Endocrine Abstracts

Background: The myocardium is a target tissue for vitamin D, that was shown to exert several effects on cardiac contractility and calcium homeostasis. We aimed to elucidate whether insufficient vitamin D status is associated with heart failure and sudden cardiac death (SCD).

Methods and Results: We measured 25-hydroxyvitamin D [25(OH)D] in 3299 Caucasian patients that were all routinely referred to coronary angiography at baseline (1997–2000). 25(OH)D was not associated with the prevalence of coronary artery disease (CAD) but was negatively correlated with N-terminal pro-B-type natriuretic peptide (NT-pro-BNP), and was an independent predictor for higher NYHA classes and impaired left ventricular function. During a median follow-up time of 7.75 years, 116 patients died due to heart failure, 90 due to myocardial infarction and 118 due to SCD. After adjustment for cardiovascular risk factors, the Cox proportional hazard ratios (with 95% confidence intervals) for death due to heart failure and for SCD were 2.84 (1.20–6.74) and 5.05 (2.13–11.97), respectively, when comparing patients with severe vitamin D deficiency [25(OH)D<10 ng/ml)] with the normal range group [25(OH)D≥30 ng/ml]. 25(OH)D was not independently associated with the risk for fatal myocardial infarction. For all statistical analyses we obtained similar results for 25(OH)D and for 1,25-dihydroxyvitamin D [1,25(OH)2D].

Conclusions: Low levels of 25(OH) and 1,25(OH)2D are independently associated with heart failure and SCD but not with fatal myocardial infarction and prevalent CAD, suggesting that possible cardioprotective effects of vitamin D might directly affect the cardiomyocytes and less the coronary vessels.