Relationship Between Sarcopenia and Frailty in the Toledo Study of Healthy Aging: A Population Based Cross-Sectional Study.

INTRODUCTION: Frailty and sarcopenia are correlates of musculoskeletal aging that represent a state of vulnerability increasing the risk of negative health outcomes. Standardized definitions are lacking for both, and sometimes both concepts are used interchangeably. However, no large study has assessed the coexistence of these 2 entities in a cohort of older community-dwelling people.

METHODS: Data were taken from the Toledo Study of Healthy Aging (TSHA), a study of community-dwelling elderly (≥65 years). The study population consists of 1611 participants with frailty and sarcopenia assessments. For sarcopenia, we used 3 criteria: European Working Group on Sarcopenia in Older People (EWGSOP), the Foundation for the National Institutes of Health (FNIH), and the FNIH fitted to the cut-off points of our population [standardized FNIH (sFNIH)]. Frailty was assessed according to the Fried criteria with cut-off points adjusted to our population. We used logistic regression to assess the relationship between sarcopenia and frailty and measures of diagnostic accuracy to evaluate the potential use of sarcopenia as a diagnostic marker for frailty.

RESULTS: The mean age of the population was 75.42 years (±5.86). Overall, 72 (4.5%) were frail. In addition, 352 (21.8%), 332 (20.6%), and 453 (28.1%) participants were considered sarcopenic according to the EWGSOP, FNIH, and sFNIH criteria, respectively. The prevalence of frailty among those with sarcopenia was 8.2% (29/352), 15.7% (52/332), and 10.4% (47/453). Moreover, among frail people, the prevalence of sarcopenia was 40.27%, 72.2%, and 65.3% according to the used criteria. Sarcopenia showed a low sensitivity (<10%) but high specificity (>97%) for the diagnosis of frailty, with a low intercorrelation (Cramer V = 0.16, 0.40, and 0.30) between the 3 criteria and frailty. Using multivariate logistic regression, frailty was associated with sarcopenia according to EWGSOP [odds ratio (OR) = 1.67, 95% confidence interval (CI) = 0.95, 2.96], FNIH (OR = 10.61, 95% CI = 5.8, 19.4), and sFNIH (OR = 6.63, 95% CI =3.5, 12.53).

CONCLUSION: Frailty and sarcopenia are distinct but related conditions. Sarcopenia is not a useful clinical biomarker of frailty, but its absence might be useful to exclude frailty.