Depressive Symptoms and Level of 25-Hydroxyvitamin D in Free-Living Oldest Old

Abstract

Background: Nowadays, the relation between hypovitaminosis D and depression has been reported and it is estimated that 1 billion people worldwide have vitamin D deficiency or insufficiency. However, the oldest old people are not included or are under-represented in most of the studies. Objective: To examine the association between depressive symptoms and 25-hydroxyvitamin D level (25(OH)Vit D) in elderly aged 80 and over who are physically more active and independent. Design: Cross-sectional study. Setting and Participants: Data collected from 182 oldest old people, aged 80 and over in the Geriatric Division from Federal University of São Paulo. Measurements: The functionality was evaluated by the Instrumental activities of their daily living (IADL). The approach of the depressive symptoms was done by the Geriatric Depression Scale (GDS) in its reduced 15 item version. 25-hydroxyvitamin D (25(OH)Vit D) analyses was done in serum sample refrigerated and protected from solar exposition. We considered deficiency serum level of 25(OH)Vit D <10ng/mL, insufficiency between 10 and 30ng/mL and sufficiency >30ng/mL. Results: According to blood level of 25(OH)Vit D we found difference between GDS score comparing the groups: “deficiency” (U=144,50; z=-3,126; p=0,002) and “insufficiency” groups (U=975,50; z=-2,793; p=0.005) are different than “sufficiency” group. Conclusion: In free-living independent oldest old people the goal of 25(OH)Vit D levels can be higher to avoid depressive symptoms, levels under 30ng/mL can be inadequate. Considering that the costs are low and side effects are not common, 25(OH)Vit D supplementation can be an important public health action.