Circulating 25-Hydroxyvitamin D Levels and Frailty Status in Older Women.
Ensrud, Kristine E.; Ewing, Susan K.; Fredman, Lisa; Hochberg, Marc C.; Cauley, Jane A.; Hillier, Teresa A.; Cummings, Steven R.; Yaffe, Kristine; Cawthon, Peggy M.; for the Study of Osteoporotic Fractures Research Group
[Article]
Journal of Clinical Endocrinology & Metabolism.
95(12):5266-5273, December 2010.
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Context: Vitamin D deficiency and frailty are common with aging, but the association between these conditions is uncertain.
Objective: To determine the association between 25-hydroxyvitamin D (25(OH)D) levels and prevalent and incident frailty status among older women.
Design: Cross-sectional and longitudinal analyses of a prospective cohort study.
Setting: Four U.S. centers.
Participants: 6307 women aged >=69 years.
Main Outcome Measures: Frailty status classified as robust, intermediate stage, or frail at baseline; and robust, intermediate stage, frail, or dead (all-cause mortality) at follow-up an average of 4.5 years later.
Results: At baseline, there was a U-shaped association between 25(OH)D level and odds of frailty with the lowest risk among women with levels 20.0-29.9 ng/ml (referent group). Compared with this group, the odds of frailty were higher among those with levels <15.0 ng/ml [multivariable odds ratio (MOR) 1.47, 95% confidence interval (CI), 1.19-1.82], those with levels 15.0-19.9 ng/ml (MOR 1.24, 95% CI 0.99-1.54), and those with levels >=30 ng/ml (MOR 1.32, 95% CI 1.06-1.63). Among 4551 nonfrail women at baseline, the odds of frailty/death (vs. robust/intermediate) at follow-up appeared higher among those with levels 15.0-19.9 ng/ml (MOR 1.21, 95% CI 0.99-1.49), but the CI overlapped 1.0. The odds of death (vs. robust/intermediate/frail at follow-up) was higher among those with levels <15.0 ng/ml (MOR 1.40, 95% CI 1.04-1.88) and those with levels 15.0-19.9 ng/ml (MOR 1.30, 95% CI 0.97-1.75), although the latter association did not quite reach significance.
Conclusion: Lower (<20 ng/ml) and higher (>=30 ng/ml) levels of 25(OH)D among older women were moderately associated with a higher odds of frailty at baseline. Among nonfrail women at baseline, lower levels (<20 ng/ml) were modestly associated with an increased risk of incident frailty or death at follow-up.
Copyright (C) 2010 by The Endocrine Society