Serum 25-hydroxyvitamin D, parathyroid hormone, and mortality in older men.

CONTEXT

Low 25-hydroxyvitamin D [25(OH)D] and high PTH may contribute to increased mortality risk in older adults.

OBJECTIVE

The aim of the study was to test the association between 25(OH)D, PTH, and mortality in older men.

DESIGN AND SETTING

The prospective Osteoporotic Fractures in Men (MrOS) study was conducted at six U.S. clinical centers.

PARTICIPANTS

We studied community-dwelling men at least 65 yr old (n = 1490).

MAIN OUTCOME MEASURE

Multivariate-adjusted proportional hazards models estimated the hazard ratio (HR) for mortality; cause of death was classified as cancer, cardiovascular, and other by central review of death certificates.

RESULTS

During 7.3 yr of follow-up, 330 (22.2%) participants died: 97 from cancer, 110 from cardiovascular disease, and 106 from other causes. The adjusted HR per sd decrease in 25(OH)D for all-cause mortality was 1.01 (95% CI, 0.89, 1.14); no association between 25(OH)D and cardiovascular or other-cause mortality was seen. Unexpectedly, lower 25(OH)D levels were modestly associated with a decreased risk of cancer mortality (adjusted HR per sd decrease, 0.80; 95% CI, 0.64, 0.99). Analyzing 25(OH)D as a categorical variable did not alter these results. Higher PTH levels (log-transformed) were associated with an increased risk of all-cause mortality (adjusted HR per sd increase, 1.15; 95% CI, 1.03, 1.29) and cardiovascular mortality (adjusted HR per sd increase in PTH, 1.21; 95% CI, 1.00, 1.45).

CONCLUSIONS

In contrast to previous studies, lower 25(OH)D levels were not associated with an increased risk of all-cause or cause-specific mortality in older men. Higher PTH levels were associated with a modest increase in mortality risk.