Low serum micronutrient concentrations predict frailty among older women living in the community

Background. Micronutrient deficiencies are common among older adults. We hypothesized that low serum micronutrient concentrations were predictive of frailty among older disabled women living in the community. Methods. We studied 766 women, aged 65 and older, from the Women's Health and Aging Study I, a population-based study of moderately to severely disabled community-dwelling women in Baltimore, Maryland. Serum vitamins A, D, E, B₆, and B ₁₂, carotenoids, folate, zinc, and selenium were measured at baseline. Frailty status was determined at baseline and during annual visits for 3 years of follow-up. Results. At baseline, 250 women were frail and 516 women were not frail. Of 463 nonfrail women who had at least one follow-up visit, 205 (31.9%) became frail, with an overall incidence rate of 19.1 per 100 person-years. Compared with women in the upper three quartiles, women in the lowest quartile of serum carotenoids (hazard ratio [HR] 1.39; 95% confidence interval [CI], 1.01-1.92), α-tocopherol (HR 1.39; 95% CI, 1.02-1.92), and 25-hydroxyvitamin D (HR 1.34; 95% CI, 0.94-1.90) had an increased risk of becoming frail. The number of nutritional deficiencies (HR 1.10; 95% CI, 1.01-1.20) was associated with an increased risk of becoming frail, after adjusting for age, smoking status, and chronic pulmonary disease. Adjusting for potential confounders, we found that women in the lowest quartile of serum carotenoids had a higher risk of becoming frail (HR 1.54; 95% CI, 1.11-2.13). Conclusions. Low serum micronutrient concentrations are an independent risk factor for frailty among disabled older women, and the risk of frailty increases with the number of micronutrient deficiencies.