Subgroup analyses in the observational studies indicated that risk of mortality was significantly higher in studies with lower baseline use of vitamin D supplements .
The effects observed for vitamin D3 supplementation remained unchanged when grouped by various characteristics .
However , for vitamin D2 supplementation , increased risks of mortality were observed in studies with lower intervention doses and shorter average intervention periods .
Conclusions Evidence from observational studies indicates inverse associations of circulating 25-hydroxyvitamin D with risks of death due to cardiovascular disease , cancer , and other causes .
Objective To evaluate the extent to which circulating biomarker and supplements of vitamin D are associated with  mortality from cardiovascular , cancer , or other conditions  , under various circumstances .
Circulating 25-hydroxyvitamin D levels and frailty status in older women.
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 prospect i ve 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
Subgroup analyses in the observational studies indicated that risk of mortality was significantly higher in studies with lower baseline use of vitamin D supplements .
The effects observed for vitamin D3 supplementation remained unchanged when grouped by various characteristics .
However , for vitamin D2 supplementation , increased risks of mortality were observed in studies with lower intervention doses and shorter average intervention periods .
Conclusions Evidence from observational studies indicates inverse associations of circulating 25-hydroxyvitamin D with risks of death due to cardiovascular disease , cancer , and other causes .
Objective To evaluate the extent to which circulating biomarker and supplements of vitamin D are associated with  mortality from cardiovascular , cancer , or other conditions  , under various circumstances .