Vitamin D deficiency is a predictor of reduced survival in patients with heart failure; vitamin D supplementation improves outcome

Vitamin D deficiency is a highly prevalent, global phenomenon. The prevalence in heart failure (HF) patients and its effect on outcome are less clear. We evaluated vitamin D levels and vitamin D supplementation in patients with HF and its effect on mortality. 25-Hydroxyvitamin D [25(OH)D] levels were evaluated in HF patients from a health maintenance organization (HMO), and compared them with those of the rest of the members of the HMO. Patients with HF (n 3009) had a lower median 25(OH)D level compared with the control group (n 46 825): 36.9 nmol/L (interquartile range 23.255.9) vs. 40.7 nmol/L (26.756.9), respectively, P 0.00001. The percentage of patients with vitamin D deficiency [25(OH)D 25 nmol/L] was higher in patients with HF compared with the control group (28 vs. 22, P 0.00001). Only 8.8 of the HF patients had optimal 25(OH)D levels (epsilon 75 nmol/L). Median clinical follow-up was 518 days. Cox regression analysis demonstrated that vitamin D deficiency was an independent predictor of increased mortality in patients with HF [hazard ratio (HR) 1.52, 95 confidence interval (CI) 1.211.92, P 0.001] and in the control group (HR 1.91, 95 CI 1.482.46, P 0.00001). Vitamin D supplementation was independently associated with reduced mortality in HF patients (HR 0.68, 95 CI 0.540.85, P 0.0001). Parameters associated with vitamin D deficiency in HF patients were decreased previous solar radiation exposure, body mass index, diabetes, female gender, pulse, and decreased calcium and haemoglobin levels. Vitamin D deficiency is highly prevalent in HF patients and is a significant predictor of reduced survival. Vitamin D supplementation was associated with improved outcome.