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 .
25-Hydroxyvitamin D, parathyroid hormone, and mortality in black and white older adults: the health ABC study.
CONTEXT Previous 25-hydroxyvitamin D [ 25(OH)D ] and mortality studies have included mostly individuals of European descent . Whether the relationship is similar in Blacks and to what extent differences in 25(OH)D explain racial disparities in mortality is unclear . OBJECTIVE The objective of the study was to examine the relationship between 25(OH)D , PTH , and mortality in Black and white community-dwelling older adults over 8.5 yr of follow-up . DESIGN AND SETTING Health ABC is a prospect i ve cohort study conducted in Memphis , TN , and Pittsburgh , PA . PARTICIPANTS Well-functioning Blacks and whites aged 71 - 80 yr with measured 25(OH)D and PTH ( n = 2638 ; 49 % male , 39 % Black ) were included in the study . MAIN OUTCOME MEASURE Multivariate-adjusted proportional hazards models estimated the hazard ratios ( HR ) for all-cause , cardiovascular , cancer , and noncancer , noncardiovascular mortality ( n = 691 deaths ) . RESULTS Mean 25(OH)D concentrations were higher in whites than in Blacks [ mean ( sd ) : 29.0 ( 9.9 ) and 20.8 ( 8.7 ) ng/ml , respectively ; P < 0.001 ] . Serum 25(OH)D by race interactions were not significant , however . Lower 25(OH)D concentrations were associated with higher mortality in Blacks and whites combined [ HR ( 95 % confidence interval [ CI ] 2.27 ( 1.59 - 3.24 ) , 1.48 ( 1.20 - 1.84 ) , and 1.25 ( 1.02 - 1.52 ) for < 10 , 10 to < 20 , and 20 to < 30 vs. ≥30 ng/ml ] . In the multivariate model without 25(OH)D , Blacks had 22 % higher mortality than whites [ HR ( 95 % CI ) 1.22 ( 1.01 , 1.48 ) ] ; after including 25(OH)D in the model , the association was attenuated [ 1.09 ( 0.90 - 1.33 ) ] . The mortality population attributable risks ( 95 % CI ) for 25(OH)D concentrations less than 20 ng/ml and less than 30 ng/ml in Blacks were 16.4 % ( 3.1 - 26.6 % ) and 37.7 % ( 11.6 - 55.1 % ) and in whites were 8.9 % ( 3.9 - 12.7 % ) and 11.1 % ( -2.7 to 22.0 % ) , respectively . PTH was also associated with mortality [ HR ( 95 % CI ) 1.80 ( 1.33 - 2.43 ) for ≥70 vs. < 23 pg/ml ] . CONCLUSIONS Low 25(OH)D and high PTH concentrations were associated with increased mortality  in Black and white community-dwelling older adults . Because 25(OH)D concentrations were much lower in Blacks , the potential impact of remediating low 25(OH)D concentrations was greater in Blacks than whites
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 .