Calcium supplementation does not increase mortality

Authors: Benjamin M P Tang and B E Christopher Nordin

Med J Aust 2008; 189 (1): 55-56. || doi: 10.5694/j.1326-5377.2008.tb01910.x
Published online: 7 July 2008

In reply: In Table 5 of Bolland and colleagues’ study, the P value after allowing for covariables was 0.08,1 which is not significant. This was without including smoking, which would undoubtedly have reduced the significance further as there were more smokers in the calcium group.

Based on Bolland and colleagues’ suggestion, we reanalysed the data by removing the group receiving vitamin D but no calcium supplements in the NoNOF (Nottingham Neck of Femur) study,2 and using data for those treated with calcium monotherapy (18.5%) compared to placebo (16.3%) in the RECORD (Randomised Evaluation of Calcium Or vitamin D) study.3 The reanalysis still failed to show any evidence of an increase in mortality (relative risk, 1.05; 95% CI, 0.88–1.26; P = 0.56).

1. Centre for Complementary Medicine Research, University of Western Sydney, Sydney, NSW.
2. School of Medicine, University of Adelaide, Adelaide, SA.

Correspondence: benjamin@clubsalsa.com.au

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