Cognition and Vitamin D in Older African-American Women- Physical performance and Osteoporosis prevention with vitamin D in older African Americans Trial and Dementia

摘要

OBJECTIVES To examine the effect of 25-hydroxyvitamin D (25(OH)D) levels recommended by Endocrine Society guidelines (30 ng/mL) on cognition in healthy older African-American women over 3 years. DESIGN Randomized, double-blind, placebo-controlled clinical trial. SETTING Bone Mineral Research Center at New York University Winthrop Hospital. PARTICIPANTS Healthy postmenopausal African American women aged 65 and older (N=260; mean age 68.2 +/- 4.9; 46% college education or higher). INTERVENTION Half of the women were randomized to receive vitamin D (adjusted to achieve a serum level 30 ng/mL) with calcium (diet and supplement total of 1,200 mg), and half were randomized to receive placebo with calcium (1,200 mg). MEASUREMENTS Cognitive assessments every 6 months using the Mini-Mental State Examination (MMSE) to detect cognitive decline. Mean MMSE scores were calculated over time for both groups. Those with MMSE scores less than 21 at baseline were excluded. RESULTS The average dose of vitamin D-3 was 3,490 +/- 1,465 IU per day, and average serum 25(OH)D at 3 years was 46.8 +/- 1.2 ng/mL in the active group and 20.7 +/- 1.1 ng/mL in the placebo group. Serum 25(OH)D concentration was maintained at greater than 30 ng/mL in 90% of the active group. Over the 3-year period, MMSE scores increased in both groups (p .001), although change over time was not significantly different between the groups. No adverse events associated with vitamin D were observed. CONCLUSION There was no difference in cognition over time between older African-American women with serum concentrations of 25(OH)D of 30 ng/mL and greater than those taking placebo. There is no evidence to support vitamin D intake greater than the recommended daily allowance in this population for preventing cognitive decline. J Am Geriatr Soc 67:81-86, 2019.