Vitamin D deficiency and frailty in older Americans

Wilhelm-Leen ER, Hall YN, deBoer IH, Chertow GM. (Stanford University School of Medicine; University of Washington; Stanford University School of Medicine, Palo Alto, CA, USA). Vitamin D deficiency and frailty in older Americans. J Intern Med 2010; 268: 171-180. Objective. To explore the relation between 25-hydroxyvitamin D deficiency and frailty. Frailty is a multidimensional phenotype that describes declining physical function and a vulnerability to adverse outcomes in the setting of physical stress such as illness or hospitalization. Low serum concentrations of 25-hydroxyvitamin D are known to be associated with multiple chronic diseases such as cardiovascular disease and diabetes, in addition to all cause mortality. Design. Using data from the Third National Health and Nutrition Survey (NHANES III), we evaluated the association between low serum 25-hydroxyvitamin D concentration and frailty, defined according to a set of criteria derived from a definition previously described and validated. Subjects. Nationally representative survey of noninstitutionalized US residents collected between 1988 and 1994. Results. 25-Hydroxyvitamin D deficiency, defined as a serum concentration < 15 ng mL-1, was associated with a 3.7-fold increase in the odds of frailty amongst whites and a fourfold increase in the odds of frailty amongst non-whites. This association persisted after sensitivity analyses adjusting for season of the year and latitude of residence, intended to reduce misclassification of persons as 25-hydroxyvitamin D deficient or insufficient. Conclusion. Low serum 25-hydroxyvitamin D concentrations are associated with frailty amongst older adults.