Calcium Intake And The Risk Of Stroke

Objective: Prospective cohort studies have suggested that dietary calcium intake is associated with the risk of stroke; however, the results are inconsistent. We conducted a meta-analysis of published studies to assess the relationship between calcium intake from diet and the risk of stroke. Methods: We searched MEDLINE, EMBASE, and OVID for relevant studies until January 1, 2013. Included for analysis were prospective cohort studies that reported relative risks with 95% confidence intervals (CI) for the association between calcium intake from diet and the stroke risk. Categorical, heterogeneity, publication bias, and subgroup analyses were performed. Results: There were 492,755 participants from ten studies, with 9,329 cases of stroke. For the highest versus lowest category of dietary calcium intake, the relative risk of total stroke was 0.87 (95% CI: 0.73-1.00). The pooled relative risk was 0.80 (95% CI: 0.62-0.98) for ischemic stroke, 0.95 (95% CI: 0.59-1.33) for intracerebral hemorrhage; and 0.96 (95% CI: 0.60-1.33) for subarachnoid hemorrhage. An inverse association between dietary calcium intake and stroke risk was observed in Asian populations (RR 0.68, 95% CI: 0.56-0.80) and participants with < 800 mg/d average dietary calcium intake (RR 0.74, 95% CI: 0.64-0.85). Conclusion: High dietary calcium intake was associated with a reduced risk of stroke, especially in ischemic stroke, Asian populations, and participants with < 800 mg/d average dietary calcium intake.