Vitamin D and mortality in older men and women.
OBJECTIVE
Vitamin D deficiency is common among the elderly and may contribute to cardiovascular disease. The aim of our study was to elucidate whether low serum levels of 25-hydroxyvitamin D [25(OH)D] are associated with an increased risk of all-cause and cardiovascular mortality.


METHODS
The Hoorn Study is a prospective population-based study among older men and women.


METHODS
Fasting serum 25(OH)D was determined in 614 study participants at the follow-up visit in 2000-2001, the baseline for the present analysis. To account for sex differences and seasonal variations of 25(OH)D levels we formed sex-specific quartiles, which were calculated from the 25(OH)D values of each season.


RESULTS
After a mean follow-up period of 6.2 years, 51 study participants died including 20 deaths due to cardiovascular causes. Unadjusted Cox proportional hazard ratios (HRs; with 95% confidence intervals) for all-cause and cardiovascular mortality in the first when compared with the upper three 25(OH)D quartiles were 2.24 (1.28-3.92; P = 0.005) and 4.78 (1.95-11.69; P = 0.001), respectively. After adjustment for age, sex, diabetes mellitus, smoking status, arterial hypertension, high-density lipoprotein-cholesterol, glomerular filtration rate and waist-to-hip ratio, the HRs remained significant for all-cause [1.97 (1.08-3.58; P = 0.027)] and for cardiovascular mortality [5.38 (2.02-14.34; P = 0.001)].


CONCLUSIONS
Low 25(OH)D levels are associated with all-cause mortality and even more pronounced with cardiovascular mortality, but it remains unclear whether vitamin D deficiency is a cause or a consequence of a poor health status. Therefore, intervention studies are warranted to evaluate whether vitamin D supplementation reduces mortality and cardiovascular diseases.
Pilz
Stefan
S
Department of Internal Medicine, Division of Endocrinology and Nuclear Medicine, Medical University of Graz, Auenbruggerplatz 15, Graz, Austria. stefan.pilz@chello.at
Dobnig
Harald
H
Nijpels
Giel
G
Heine
Robert J
RJ
Stehouwer
Coen D A
CD
Snijder
Marieke B
MB
van Dam
Rob M
RM
Dekker
Jacqueline M
JM
D000368:Aged; D002318:Cardiovascular Diseases / Q000097:blood* / Q000401:mortality*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D014808:Vitamin D Deficiency / Q000097:blood* / Q000401:mortality*
D014807:Vitamin D; C104450:25-hydroxyvitamin D