Abstract
BACKGROUND: Debate exists about the relationship between hypovitaminosis D and cardiovascular (CVD) risk. METHODS: This study investigated baseline (n=2,271) 25-hydroxyvitamin D (25(OH)D) and baseline and 4 year (n=1,957) CVD risk in a cohort of Finnish middle-aged male smokers. RESULTS: The prevalences of measured hypertension, high pulse rate, diabetes, and coronary heart disease were 63%, 16%, 5%, and 10% at baseline and were 64%, 20%, 6%, and 16% at 4 years after baseline. The mean 25(OH)D was 41±18 nmol/L. At baseline, systolic blood pressure (β = -0.048; P = 0.02), and pulse rate (β = -0.043; P = 0.04) were both associated with lower 25(OH)D levels but not coronary heart disease or diabetes prevalence. On remeasuring CVD risk 4 years after baseline, the only significant association with baseline 25(OH)D levels was high pulse rate (β = -0.077; P = 0.001). In addition, a higher 25(OH)D level at baseline was associated with a change in pulse rate (β = -0.055; P = 0.01). These trends for hypertension (baseline) and high pulse rate (baseline and 4 years after baseline) were also seen on adjusted categorical analysis (P trend < 0.05). CONCLUSIONS: Vitamin D deficiency at baseline was associated with hypertension in Finnish male smokers, but not after 4 years. These results are consistent with recent findings in other large cohort studies with measured blood pressure. Change in pulse rate over time continued to be significantly associated with lower 25(OH)D baseline levels; this new finding should be investigated further.