Purpose: To investigate the prevalence and predictive value of three commonly used sarcopenia definitions for the risk of injurious falls in a population of older Swedish women.
Methods: 2,883 older women aged 75 to 80 years were included. Sarcopenia was defined based on the Sarcopenia Definitions and Outcomes Consortium (SDOC) (low handgrip strength and gait speed), revised European Working Group on Sarcopenia in Older People (EWGSOP2) and Asian Working Group for Sarcopenia (AWGS) (low appendicular lean mass index (ALMI; appendicular lean mass (kg)/height (m2)) and hand grip strength (kg)) definitions. ALMI was obtained from dual-energy X-ray absorptiometry (DXA) (Hologic Discovery A). Self-reported questionnaires captured the occurrence of falls in the past 12 months and fracture risk assessment (FRAX)-based clinical risk factors. Incident injurious falls, without concurrent fracture, were identified using national registers and ICD-10 codes. Cox regression (hazard ratios (HR) and 95% confidence intervals (CI)) analyses were performed without adjustment and after adjustment for age, FRAX variables and previous falls.
Results: Sarcopenia prevalence was 4% (n=129) defined by SDOC, 12% (n=360) for EWGSOP2 and 10% (n=296) for AWGS. During a median (IQR) follow-up time of 6.6 (5.7-7.3) years there were 491 injurious falls without fracture. Sarcopenia according to EWGSOP2 and AWGS was not associated with an increased risk of injurious falls, regardless of adjustment (p>0.05). Individuals with sarcopenia defined by SDOC had more than 2-folds increased risk of injurious falls compared with women without sarcopenia (HR: 2.27; CI:1.64-3.15). After adjusting for confounders there was a slightly attenuated association between SDOC prevalence and injurious falls (HR:1.85; Cl:1.32-2.60).
Conclusion: These findings suggest that sarcopenia definitions confined to muscle function and strength such as SDOC, rather than including DXA-based ALMI (EWGSOP2 and AWGS), lowers the prevalence but improves prediction of injurious falls in this population of Swedish older women.