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Meta-analysis of all-cause mortality according to serum 25-hydroxyvitamin D
Cedric F Garland1, June Jiwon Kim, Sharif Burgette Mohr
1Cedric F. Garland and Edward D. Gorham are with the Division of Epidemiology, Department of Family and Preventive Medicine, University of California San Diego, La Jolla. June J. Kim, Sharif B. Mohr, and Kenneth Zeng are with Leidos Biomedical Research, Inc., San Diego. William B. Grant is with Sunlight and Nutrition Research Center, San Francisco, CA. Edward L. Giovannucci is with departments of Epidemiology and Nutrition, Harvard School of Public Health, Boston, MA. Leo Baggerly is with Research Department, GrassrootsHealth, San Diego. Heather Hofflich and Joe W. Ramsdell are with Internal Medicine Group, Department of Medicine, University of California San Diego. Robert P. Heaney is with Department of Medicine, Creighton University, Omaha, NE.
Abstract:
We examined the relationship between serum 25-hydroxyvitamin D (25[OH]D) and all-cause mortality. We searched biomedical databases for articles that assessed 2 or more categories of 25(OH)D from January 1, 1966, to January 15, 2013. We identified 32 studies and pooled the data. The hazard ratio for all-cause mortality comparing the lowest (0-9 nanograms per milliliter [ng/mL]) to the highest (> 30 ng/mL) category of 25(OH)D was 1.9 (95% confidence interval = 1.6, 2.2; P < .001). Serum 25(OH)D concentrations less than or equal to 30 ng/mL were associated with higher all-cause mortality than concentrations greater than 30 ng/mL (P < .01). Our findings agree with a National Academy of Sciences report, except the cutoff point for all-cause mortality reduction in this analysis was greater than 30 ng/mL rather than greater than 20 ng/mL.
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