Low 25-hydroxyvitamin D is associated with increased mortality in female nursing home residents.
BACKGROUND
Vitamin D deficiency contributes to skeletal diseases and is highly prevalent among institutionalized elderly patients. Whether low 25-hydroxyvitamin D (25[OH]D) concentrations are an independent risk factor for mortality in these patients is, however, unclear.


OBJECTIVE
We aimed to evaluate whether 25(OH)D concentrations are associated with mortality.


METHODS
This is a prospective cohort study among elderly female patients (age >70 yr) recruited from 95 nursing homes in Austria.


METHODS
We calculated Cox proportional hazard ratios (HR) for all-cause mortality according to 25(OH)D quartiles.


RESULTS
We examined 961 study participants (age 83.7 ± 6.1 yr). Median 25(OH)D concentration was 17.5 (interquartile range 13.7-25.5) nmol/liter, and 93% of our cohort had 25(OH)D levels below 50 nmol/liter. During a mean follow-up time of 27 ± 8 months, 284 patients died. Compared with the fourth quartile (25[OH]D >25.5 nmol/liter), the age-adjusted HR (with 95% confidence interval) was 1.49 (1.07-2.10) in the first 25(OH)D quartile (25[OH]D <14.0 nmol/liter), and this association remained significant after multivariate adjustments (HR = 1.56; 95% confidence interval = 1.01-2.40).


CONCLUSIONS
This Austrian study suggests that the majority of institutionalized female patients are vitamin D deficient during winter and that there was an inverse association of 25(OH)D and mortality. These data underscore the urgent need for effective strategies for the prevention and treatment of vitamin D deficiency, in particular in the setting of nursing homes.
Department of Internal Medicine, Division of Endocrinology and Metabolism, Medical University of Graz, Auenbruggerplatz 15, 8036 Graz, Austria. stefan.pilz@chello.at
Stefan
S
Pilz
Harald
H
Dobnig
Andreas
A
Tomaschitz
Katharina
K
Kienreich
Andreas
A
Meinitzer
Claudia
C
Friedl
Doris
D
Wagner
Claudia
C
Piswanger-Sölkner
Winfried
W
März
Astrid
A
Fahrleitner-Pammer
D015652:25-Hydroxyvitamin D 2 / Q000097:blood*; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging; D001317:Austria / Q000453:epidemiology; D002112:Calcifediol / Q000097:blood*; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D016330:Frail Elderly; D006707:Homes for the Aged; D006801:Humans; D009026:Mortality; D015999:Multivariate Analysis; D009735:Nursing Homes; D015995:Prevalence; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012621:Seasons; D014808:Vitamin D Deficiency / Q000097:blood* / Q000453:epidemiology
D015652:25-Hydroxyvitamin D 2; D002112:Calcifediol