Relationship Between Dietary Vitamin D and Deaths From Stroke and Coronary Heart Disease: The Japan Collaborative Cohort Study.

Background and purpose: There is growing evidence about the importance of vitamin D for cardiovascular health. Therefore, we examined the relationship between dietary vitamin D intake and risk of mortality from stroke and coronary heart disease in Japanese population.

Methods: A prospective study encompassing 58 646 healthy Japanese adults (23 099 men and 35  547 women) aged of 40 to 79 years in whom dietary vitamin D intake was determined via a self-administered food frequency questionnaire. The median follow-up period was 19.3 years (1989-2009). The hazard ratios and 95% confidence intervals of mortality were calculated using categories of vitamin D intake.

Results: During 965 970 person-years of follow-up, 1514 stroke and 702 coronary heart disease deaths were documented. Vitamin D intake was inversely associated with risk of mortality from total stroke especially intraparenchymal hemorrhage but not from coronary heart disease; the multivariable hazard ratios (95% confidence intervals) for the highest (≥440 IU/d) versus lowest (<110 IU/D) categories of vitamin D intake were 0.70 (0.54-0.91; P for trend=0.04) for total stroke and 0.66 (0.46-0.96; P for trend=0.04) for intraparenchymal hemorrhage.

Conclusions: Dietary vitamin D intake seems to be inversely associated with mortality from stroke.