25-hydroxyvitamin D Levels are Associated with Cognitive Dysfunction in Type 2 Diabetes and the Metabolic Syndrome: A Preliminary Examination

Abstract

Background: Type 2 diabetes (T2DM) and metabolic syndrome are linked to pathological changes in the brain and increased likelihood of cognitive impairment. 25-hydroxyvitamin D insufficiency is commonly found in this population and is associated with cognitive dysfunction in other patient groups. This preliminary study sought to examine whether 25hydroxyvitamin D levels are is associated with cognitive deficits in this population. Methods: Twenty individuals with T2DM and metabolic syndrome (n = 20, aged 45 to 72) were recruited for this cross-sectional study from a subspecialty diabetes center. All completed computerized cognitive testing and clinical evaluation, including assessment of circulating 25-hydroxyvitamin D values. Pearson correlations determined the association between 25-hydroxyvitamin D value and test performance. Results: Cognitive dysfunction was prevalent, as 45% met criteria for MCI and participants exhibited clinically meaningful deficits on an average of 2.4 +/-2.0 tests.