Prognostic value of a rapid sarcopenia measure in acutely ill older adults

Abstract

Background: Current recommendations to assess sarcopenia requiring specialized equipment hinder its use as a prognostic tool in busy acute settings.

Aims: To investigate the prognostic value of a rapid sarcopenia measure in acutely ill older outpatients for 1-year adverse outcomes.

Methods: Prospective study with 665 acutely ill older adults (mean age 78.7 ± 8.3 years; 63% women) in need of intensive management to avoid hospital admission. Sarcopenia was screened upon admission, defined as the presence of both low muscle strength and low muscle mass. Low muscle strength was determined by handgrip strength according to the cutoffs of the Foundation for the National Institutes of Health (<16 kg for women and <26 kg for men). Low muscle mass was assessed by calf circumference, a validated surrogate measure of skeletal muscle mass, using previously established thresholds (≤33 cm for women and ≤34 cm for men). Outcomes were time to hospitalization, new dependence in basic activities of daily living (ADL), worsening walking ability, and death. To investigate the association of sarcopenia and its components with outcomes we used hazard models, considering death as a competing risk, adjusted for sociodemographic factors, Charlson comorbidity index, cognitive impairment, depressive symptoms, and weight loss.

Results: On admission, 203 (31%) patients had sarcopenia. Comparing 1-year adverse outcomes between older adults with and without sarcopenia, respectively, cumulative incidences for hospitalization were 46% vs 32% (adjusted sub-hazard ratio [sHR] = 1.53; 95% CI = 1.16-2.04), for new ADL dependence, 47% vs 24% (adjusted sHR = 1.78; 95% CI = 1.31-2.42), for worsening walking ability, 28% vs 13% (adjusted sHR = 1.93; 95% CI = 1.28-2.90), and for death, 22% vs 10% (adjusted HR = 1.69; 95% CI = 1.05-2.73). Low muscle strength alone was associated with all outcomes, and low muscle mass was associated with all outcomes except mortality.

Conclusion: Sarcopenia was a strong predictor of 1-year adverse outcomes among acutely ill older outpatients. Combining handgrip strength with calf circumference may be a practical and efficient approach to screen for sarcopenia, and thereby identify high-risk older adults in busy clinical settings.

Keywords: Acute care; Calf circumference; Grip strength; Prognosis; Sarcopenia; Screening.