[Vitamin D deficiency in elderly men living in urban areas, at home or in institutions].

Objectives: Many studies report severe vitamin D deficiency in the elderly and its involvement in various health problems (not limited to bone metabolism disorders). Most papers concern elderly women, however, and little is known about this problem among elderly men. This study focused on vitamin D deficiency in elderly men living in urban areas, whether at home or in an institution.

Methods: Between December 2005 and June 2006, we randomly recruited from general practices 336 men aged 65 years or more, living either at home or in institutions for the elderly. The variables studied were: age, residence (home or institution), fall and fracture history, independence (Katz), mobility (TUG), balance, outdoor walking, blood 25-OH-D level, glomerular filtration rate (MDRD) and PINI index.

Results: Of the 336 men, 45 (13%) were excluded because they were already receiving vitamin D treatment. The study thus included 291 patients, 174 community-dwelling and 117 institutionalized. The latter were significantly older and had less independence. Their 25-OH-D levels were also significantly lower than for community-dwelling subjects. The prevalence of severe vitamin D deficiency (25-OH-D < 12 ng/mL) was 79% among men in institutions and 57% among those living in the community (p<0.0001), and for mild and moderate vitamin D deficiency (12-32 ng/mL), 21% and 42%, respectively. Overall, only 2 men, both living at home, had normal vitamin D levels (25-OH-D > or = 32 ng/mL). In institutions, factors predictive of severe deficiency were TUG > or = 30s, walking distance < or = 100 m and lack of outdoor walking. Among the men living at home, none of the variables studied was associated with severe vitamin D deficiency.

Discussion: Potential biases of the study are discussed. Seasonal variations of vitamin D levels were small and comparable in both groups. The study confirms the high prevalence of vitamin D deficiency in elderly men. These results could probably be extended to other European cities with similar characteristics. The problem of interpreting 25-OH-D results with respect to current laboratory norms for defining severe or moderate vitamin D deficiency (12 and 32 ng/mL, respectively) is also discussed.

Conclusion: Vitamin D deficiency is widespread and severe in elderly men, especially those living in institutions. Moderate to severe deficiency is also frequent among men living at home. Vitamin D supplementation should be routinely prescribed in institutions for the elderly and probably also to any individual over 65 years. Laboratory norms should be harmonized and consistent with recent medical evidence.