Is Vitamin D3 Worth Giving to Our Patients with Mild Cognitive Impairment?

Jonathan Silver, MD reviewing Hu J et al. J Neurol Neurosurg Psychiatry 2018 Oct 2Improvements in cognition and lipid levels were seen after 1 year of supplementation in a study from China.Many patients with mild cognitive impairment (MCI) progress to Alzheimer disease. No preventive intervention is proven, although we tell our patients to have a healthy diet, get sleep, and exercise — and multiple supplements are advertised for “brain health.” In a randomized, placebo-controlled trial, researchers in China assessed effects of 1 year of vitamin D3 supplementation (400 IU/day) on cognition and lipid levels in 181 patients who met criteria for MCI (mean age, 67; 45% men).Treatment groups did not differ on history of diabetes or hypertension, mental status scores, and vitamin D levels. At the 12-month assessment, the vitamin-D group significantly improved from baseline and had better scores than the placebo group on multiple measures in the Chinese version of the Wechsler Adult Intelligence Scale–Revised (full-scale IQ, verbal IQ, performance IQ, and multiple subtests). The vitamin-D group also had higher 25-D and 1,25-D levels. Levels of total cholesterol, triglycerides, HDL, and LDL decreased in the vitamin-D group but increased in the placebo group. Total cholesterol concentration in the vitamin-D group was inversely associated with full IQ.