Dietary vitamin D intake, cardiovascular disease and cardiometabolic risk factors: a sex-based analysis from the ATTICA cohort study

Background The present study aimed to evaluate the association between dietary vitamin D intake and 10-year first fatal/nonfatal cardiovascular disease (CVD), conventional CVD risk factors and surrogate markers related to inflammation, coagulation, insulin resistance, liver and renal function. Methods The ATTICA study was conducted during 2001-2012 including 1514 men and 1528 women (aged >18 years) from the greater Athens area, Greece. Dietary assessment was based on a validated semi-quantitative food frequency questionnaire. Daily intake of vitamin D was calculated using a standardised food database. Follow-up (2011-2012) was achieved in 2020 participants (n = 317 cases). Results Ranking from first to third vitamin D tertile, CVD events were 24%, 17% and 12% for men (P = 0.002) and 14%, 10% and 11% for women (P = 0.59). Inverse associations between vitamin D and CVD in total sample [hazard ratio (HR) = 0.76 95% confidence interval (CI) = 0.60-0.97] and in men (HR = 0.66 95% CI = 0.49-0.89) were observed, and lost after adjusting for inflammation/coagulation markers; for women, no significant trends were observed. Regarding 10-year onset of conventional risk factors, inverse associations of vitamin D with hypertension in men (HR = 0.62 95% CI = 0.39-0.99) and transition to metabolically unhealthy status in women (HR = 0.69 95% CI = 0.51-0.93) were observed. Significant inverse associations for C-reactive protein, interleukin-6 and fibrinogen in both sexes, whereas these were revealed only in women for insulin resistance. Conclusions Contradicting the neutral/modest associations in vitamin-D supplementation trials, increased food-generated vitamin D may protect against hard and intermediate CVD endpoints, implying different paths between sexes.