Dement Geriatr Cogn Disord 2012 Vol. 33, No. 5, 2012 ;33:297-305
Thorleif Etgena,b thorleif.etgen at klinikum-traunstein.de, Dirk Sanderc,d, Horst Bickela, Kerstin Sanderd, Hans Förstla
A Department of Psychiatry and Psychotherapy, Technische Universität München,
B Department of Neurology, Kliniken Südostbayern – Klinikum Traunstein,
C Department of Neurology, Benedictus Krankenhaus Tutzing, and
D Department of Neurology, Technische Universität München, Munich, Germany
Background: Recent preventive strategies for patients with cognitive impairment include the identification of modifiable somatic risk factors like vitamin D deficiency.
Methods: A systematic literature research and meta-analysis were conducted to assess the association of cognitive impairment and vitamin D deficiency.
Results: 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).
Conclusions: 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.
Copyright © 2012 S. Karger AG, Basel