Affiliation:
1. Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University Anam Hospital Korea University College of Medicine Seoul Republic of Korea
Abstract
AbstractBackgroundCurrent evidence regarding the mortality outcomes associated with calcium supplementation with or without low‐dose vitamin D is conflicting.ObjectivesTo investigate the effects of calcium supplementation with or without vitamin D on all‐cause and cause‐specific mortalities in a large‐scale cohort.MethodsThis study used data from the Korean National Health Insurance System database and National Death Registry. A total of 27,846 participants aged >55 years who had taken calcium supplements with or without vitamin D for at least 90 days (calcium supplementation only [CaO], n = 6256; calcium supplementation in combination with vitamin D [CaD], n = 21,590) were matched in a 1:1 ratio to those who did not take calcium or vitamin D supplements (control group) using propensity scores.ResultsNo difference in all‐cause mortality risk was found between the CaO and control groups: (adjusted hazard ratio [HR] = 1.00; 95% confidence interval [CI]: 0.92–1.10). However, all‐cause mortality was lower in the CaD group (HR = 0.85; 95% CI: 0.80–0.89) compared with that in the control group. Mortality risk associated with cardiovascular disease (CVD) was decreased in the CaD group when the daily vitamin D dose received was less than 1000 IU (HR = 0.72; 95% CI: 0.64–0.81). Subgroup analysis showed significant effect of vitamin D with calcium in individuals who were female, aged ≥65 years or had previous history of cancer or CVD.ConclusionIn combination with calcium, vitamin D supplementation provides better outcomes for all‐cause mortality, particularly CVD‐associated mortality, in a duration‐dependent manner.