Low vitamin D levels increase the risk of type 2 diabetes in older adults: A systematic review and meta-analysis

摘要

Low serum levels of 25 hydroxyvitamin D (250HD) (hypovitaminosis D) is common in older adults and associated with several negative outcomes. The association between hypovitaminosis D and diabetes in older adults is equivocal, however. We conducted a meta-analysis investigating if hypovitaminosis D is associated with diabetes in prospective studies among older participants. Two investigators systematically searched major electronic databases, from inception until 10/07/2016. The cumulative incidence of diabetes among groups was estimated according to baseline serum 250HD levels. Random effect models were used to assess the association between hypovitaminosis D and diabetes at follow-up. From 4268 non-duplicate hits, 9 studies were included; these followed 28,258 participants with a mean age of 67.7 years for a median of 7.7 years. Compared with higher levels of 250HD, lower levels of 250HD were associated with a higher risk of developing diabetes (6 studies; n = 13,563; RR= 1.31; 95% CI: 1.11-1.54; I-2 = 37%). The findings remained significant after adjusting for a median of 11 potential confounders in all the studies available (9 studies; n = 28,258; RR= 1.17; 95% CI: 1.03-1.33; p = 0.02; I-2 = 0%). In conclusion, our data suggest that hypovitaminosis D is associated with an elevated risk of future diabetes in older people. Future longitudinal studies are required and should seek to confirm these findings and explore potential pathophysiological underpinnings. (C) 2017 Elsevier B.V. All rights reserved.