Vitamin D Deficiency, Cognitive Impairment and Dementia: A Systematic Review and Meta-Analysis
Dementia and Geriatric Cognitive Disorders, 07/05/2012
Etgen T et al. – Methodological limitations of these studies comprise heterogeneity of study populations, different forms of cognitive assessment, the problem of reverse causality, different definitions of vitamin D deficiency and inconsistent control for confounders. As the value of vitamin D substitution in cognitive impairment remains doubtful, a long–time major placebo–controlled randomized trial of vitamin D supplementation in participants with mild cognitive impairment (MCI) should be started.Methods
- A systematic literature research and meta–analysis were conducted to assess the association of cognitive impairment and vitamin D deficiency.
- Data from cross–sectional and longitudinal studies suggest an association between cognitive impairment and vitamin D deficiency.
- Meta–analysis of 5 cross–sectional and 2 longitudinal studies comprising 7,688 participants showed an increased risk of cognitive impairment in those with low vitamin D compared with normal vitamin D (OR 2.39, 95% CI 1.91–3.00; p < 0.0001).