Hypovitaminosis D predicts more rapid and severe cognitive deterioration in ethnically diverse older adults with and without dementia

Vitamin D status and rates of cognitive decline in a multiethnic cohort of older adults. Context Hypovitaminosis D is a rule rather than an exception in older adults, with a prevalence of up to 90% according to the definition used.1 There is a growing body of evidence linking vitamin D to non-skeletal targets, including brain health and function.2 The neurosteroid properties of vitamin D include, among others, regulation of calcium homeostasis, clearance of amyloid-β peptide, antioxidant and anti-inflammatory actions.3 Based on previous epidemiological data reporting the structural changes in brain and cognitive disorders in the case of hypovitaminosis D in older adults, this study by Miller and colleagues aimed at evaluating the latter relationship in a multiethnic cohort of older adults with a high proportion of African-American and Hispanic participants who are at particular risk of hypovitaminosis D.1 Methods The purpose was to assess associations between vitamin D status and trajectories of change in the subdomains of cognitive function in a cohort of ethnically diverse older adults. During follow-up, the rates of decline in episodic memory and executive function were greater among participants with vitamin D deficiency and insufficiency compared to those with adequate concentrations, even after controlling for potential confounders.