Calcium supplementation and the risk of dementia in the Perth Longitudinal Study of Aging Women: a post-hoc analysis of a randomised clinical trial for fracture prevention
Year: 2025
Type: article
Abstract: Background: Concerns have been raised around whether calcium supplements increase dementia risk. This post-hoc analysis of a five-year double-blind, placebo-controlled randomised trial of calcium supplements for primary fracture prevention evaluated the long-term risk for dementia in older women, randomised to either calcium supplements or placebo. Methods: 1460 community-dwelling dementia-free Australian women (≥70 years) were randomised to 1200 mg/day calcium carbonate (n = 730) or placebo (n = 730) for five years and were observed for an additional 9.5 years afterwards. Over 14.5 years, all-cause dementia events (comprising dementia-related hospitalisations and/or deaths) were identified from linked health records. The influence of calcium supplementation on dementia outcomes were examined using Kaplan-Meier survival curves and Cox regression under intention-to-treat (ITT) and per-protocol (PP, ≥80% tablet compliance, n = 830; 50.6% calcium supplements) criteria. Findings: Mean baseline age was 75.1 ± 2.7 years. Dementia events were recorded in 269 women (18.4%), comprising 243 hospitalisations (16.6%) or 114 deaths (7.8%). No differences in the cumulative dementia-free survival rates were observed between groups in ITT and PP analyses. Compared to placebo, calcium supplements did not increase risk of dementia-related events (unadjusted ITT hazard ratio [HR] 0.90, 95% confidence interval (CI) 0.71-1.15), hospitalisations (HR 0.89, 95% CI 0.69-1.15) or deaths (HR 0.78, 95% CI 0.54-1.13). Similar results were observed in PP analyses. Interpretation: Calcium supplementation for five years did not increase the risk of all-cause dementia events over 14.5 years in community-dwelling older women. Findings do not support concerns that calcium supplementation increases long-term risk of dementia. Funding: National Health and Medical Research Council of Australia.
Language: English
Subfield: Psychiatry and Mental health
Field: Medicine
Domain: Health Sciences
Open Access status: gold
Estimated APC paid: $4,250
Funders: U.S. Department of Justice, Royal Perth Hospital Medical Research Foundation, Curtin University, Malaysia, National Heart Foundation of Australia, Curtin University of Technology, Department of Health, Government of Western Australia, Dementia Australia, National Coronial Information System, Medical Research Council, National Health and Medical Research Council, Western Australian Future Health and Innovation Fund, Government of Western Australia
OpenAlex ID: W4414866914