The longitudinal associations of sarcopenia definitions with functional deterioration: a comparative study

Area of Science:

• Gerontology
• Clinical Medicine
• Public Health

Background:

• Probable sarcopenia is a known predictor of functional limitations in the elderly.
• The optimal diagnostic thresholds for sarcopenia, standard versus population-specific, remain unclear for predicting functional impairment.

Purpose of the Study:

• To compare the predictive accuracy of standard (EWGSOP2) and population-specific thresholds for probable sarcopenia in relation to functional deterioration.
• To determine the prevalence of probable sarcopenia using different thresholds in older outpatients.

Main Methods:

• A retrospective, longitudinal follow-up study of 1970 older outpatients.
• Handgrip strength (HGS) measured using a Jamar dynamometer.
• Activities of Daily Living (ADL) and Instrumental ADL (IADL) assessed using Katz and Lawton scales.
• Cox regression models adjusted for age, sex, and nutritional status.

Main Results:

• Prevalence of probable sarcopenia was 8.7% (standard) vs. 35.4% (population-specific).
• Population-specific thresholds, unlike standard ones, were significantly associated with ADL and IADL deterioration (p < 0.001).
• Probable sarcopenia defined by population-specific cut-offs independently predicted IADL impairment in multivariate analyses.

Conclusions:

• Population-specific thresholds for diagnosing probable sarcopenia are more reliable predictors of longitudinal functional decline in older outpatients.
• Evidence supports the use of population-specific cut-offs for sarcopenia diagnosis in clinical practice.