Vitamin D deficiency and mortality.
OBJECTIVE
To summarize recent findings on vitamin D deficiency and mortality. The serum concentration of 25-hydroxyvitamin D [25(OH)D], the metabolic precursor of the vitamin D hormone calcitriol, is the standard for assessing vitamin D status. Deficient 25(OH)D concentrations (<25 nmol/l) are prevalent in Europe and North America.


RESULTS
Several large nonrandomized studies indicate that different from adequate 25(OH)D concentrations (>75 nmol/l), deficient 25(OH)D concentrations are associated with excess mortality in the general population and in patients with increased cardiovascular disease risk. Results support an earlier meta-analysis of controlled trials that were not primarily designed to assess mortality showing a survival benefit of vitamin D supplementation over no supplementation in middle-aged and elderly persons. In patients with advanced chronic diseases such as end-stage heart failure, however, circulating calcitriol predicts mid-term mortality better than 25(OH)D does. Available data indicate that these patients may enter a vicious cycle of low calcitriol, increased inflammation markers, and renal impairment, which may be difficult to escape by simple vitamin D supplementation.


CONCLUSIONS
Accumulating evidence suggests that vitamin D deficiency is linked to excess mortality. However, future studies should clarify to which extent vitamin D supplementation can improve survival in the aging population and in specific patient groups.
Zittermann
Armin
A
Clinic for Thoracic and Cardiovascular Surgery, Heart Center North Rhine-Westfalia, Ruhr University Bochum, Georgstrsse 11, D-32545 Bad Oeynhausen, Germany. azittermann@hdz-nrw.de
Gummert
Jan F
JF
Börgermann
Jochen
J
D000328:Adult; D000368:Aged; D002117:Calcitriol / Q000097:blood* / Q000627:therapeutic use; D002318:Cardiovascular Diseases / Q000097:blood / Q000209:etiology / Q000401:mortality*; D019587:Dietary Supplements; D005060:Europe / Q000453:epidemiology; D006801:Humans; D007676:Kidney Failure, Chronic / Q000188:drug therapy; D008875:Middle Aged; D009656:North America / Q000453:epidemiology; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood / Q000627:therapeutic use*; D014808:Vitamin D Deficiency / Q000097:blood / Q000150:complications / Q000401:mortality*
D014807:Vitamin D; C104450:25-hydroxyvitamin D; D002117:Calcitriol