Sarc-frailty: towards an integrated view of ageing

Abstract

Objectives: Sarcopenia and frailty have both been related to adverse events in ageing, but have long been studied in parallel. The purpose of this study was to provide a better depiction of ageing by taking the advantages of both entities.

Study design: 2532 participants were enrolled from the National Health and Nutrition Examination Survey 1999-2002. A new diagnostic entity, sarc-frailty, was established by merging the diagnostic elements of both sarcopenia and frailty.

Main outcome measures: Cox proportional hazard models, Kaplan-Meier curve, and receiver operating characteristic (ROC) curve analysis were utilized to compare the hazard ratios and predictive power in relation to mortality of sarcopenia, frailty, and sarc-frailty. Two different classification strategies, categorical and scoring, were used as alternative assessment methods.

Results: The median follow-up duration was 67.49 months, and no participants were lost to follow-up. ROC analysis revealed the highest area under curves (AUC) in sarc-frailty by both categorical and scoring classification (AUC = 0.660, p value <0.001 and AUC = 0.697, p value <0.001, respectively), indicating the best predictive ability in relation to mortality. Kaplan-Meier analysis also demonstrated the shortest overall survival for sarc-frailty with both classifications (p value both <0.001). In addition, hazard ratios (HRs) of sarc-frailty with both classifications were higher than their counterparts for sarcopenia and frailty (HR = 12.599, 95 % CI = 7.780 to 20.403, p < 0.001 by categorical method, and HR = 20.121, 95 % CI = 8.101 to 49.973, p < 0.001 by scoring classification). Moreover, the scoring classification revealed a more delicate hierarchical structure of mortality levels than the categorical classification.

Conclusions: Sarc-frailty had a better predictive ability in relation to mortality. Considering that ageing well is a holistic health-care issue, our new entity, along with the scoring method, provides clinicians with more effective tools in geriatric assessment.

Keywords: Ageing; Frailty; Mortality; Sarc-frailty; Sarcopenia.