Although gait speed is a widely used measure in older people, testing methods are highly variable. We conducted a systematic review to investigate the influence of testing procedures on resulting gait speed. We followed the PRISMA checklist for this systematic review. Two independent reviewers screened Pubmed and Embase for publications on pairwise comparisons of testing procedures of usual gait speed. Descriptives were abstracted from the included publications using a predefined extraction tool by two independent reviewers. We defined the cut-off for the minimal clinically imporant diffence in gait speed as 0.1 m/sec. Of a total of 2109 records identified for screening, 29 reports on 53 pairwise comparisons were analyzed. The median (range) difference in gait speed for dynamic versus static start was 0.06 (-0.02 to 0.35) m/sec (14 reports); for longer versus shorter test distance 0.04 (-0.05 to 0.23) m/sec (14 reports); for automatic versus manual timing 0.00 (-0.05 to 0.07) m/sec (12 reports), for hard versus soft surfaces -0.11 (-0.18 to 0.08) m/sec (six reports), and electronic walkways versus usual walk test 0.04 (-0.08 to 0.14) m/sec (seven reports), respectively. No report compared the effect of finishing procedures. The type of starting procedure, the length of the test distance, and the surface of the walkway may have a clinically relevant impact on measured gait speed. Manual timing resulted in statistically significant differences of measured gait speed as compared to automatic timing, but was below the level of clinical importance. These results emphasize that it is key to use a strictly standardized method for obtaining a reliable and valid measurement of gait speed.

Objectives Multinational prevalence data on sarcopenia among generally healthy older adults is limited. The aim of the study was to assess prevalence of sarcopenia in the DO-HEALTH European trial based on twelve current sarcopenia definitions. Setting and Participants This is an analysis of the DO-HEALTH study including 1495 of 2157 community-dwelling participants age 70+ years from Germany, France, Portugal, and Switzerland with complete measurements of the sarcopenia toolbox including muscle mass by DXA, grip strength, and gait speed. Measurements The twelve sarcopenia definitions applied were Asian Working Group on Sarcopenia (AWGS1), AWGS2, Baumgartner, Delmonico, European Working Group on Sarcopenia in Older People (EWGSOP1), EWGSOP2, EWGSOP2-lower extremities, Foundation for the National Institutes of Health (FNIH1), FNIH2, International Working Group on Sarcopenia in Older People (IWGS), Morley, and Sarcopenia Definitions and Outcomes Consortium (SDOC). Results Mean age was 74.9 years (SD 4.4); 63.3% were women. Sarcopenia prevalence ranged between 0.7% using the EWGSOP2 or AWGS2 definition, up to 16.8% using the Delmonico definition. Overall, most sarcopenia definitions, including Delmonico (16.8%), Baumgartner (12.8%), FNIH1(10.5%), IWGS (3.6%), EWGSOP1 (3.4%), SDOC (2.0%), Morley (1.3%), and AWGS1 (1.1%) tended to be higher than the prevalence based on EWGSOP2 (0.7%). In contrast, the definitions AWGS2 (0.7%), EWGSOP2-LE (1.1%), FNIH2 (1.0%) — all based on muscle mass and muscle strength — showed similar lower prevalence as EWGSOP2 (0.7%). Moreover, most sarcopenia definitions did not overlap on identifying sarcopenia on an individual participant-level. Conclusion In this multinational European trial of community-dwelling older adults we found major discordances of sarcopenia prevalence both on a population- and on a participant- level between various sarcopenia definitions. Our findings suggest that the concept of sarcopenia may need to be rethought to reliably and validly identify people with impaired muscle health.

Over the last 3 years new definitions of sarcopenia by the Sarcopenia Definition and Outcome Consortium (2020, SDOC), European Working Group on Sarcopenia in Older People (2019, EWGSOP2) and Asian Working Group on Sarcopenia (2019, AWGS2) have been proposed. The objective of this scoping review was to explore predictive validity of these current sarcopenia definitions for clinical outcomes. We followed the PRISMA checklist for scoping reviews. Based on a systematic search performed by two independent reviewers of databases (Pubmed and Embase) articles comparing predictive validity of two or more sarcopenia definitions on prospective clinical outcomes published since January 2019 (the year these definitions were introduced) were included. Data were extracted and results collated by clinical outcomes and by sarcopenia definitions, respectively. Of 4493 articles screened, 11 studies (mean age of participants 77.6 (SD 5.7) years and 50.0% female) comprising 82 validity tests were included. Overall, validity tests on the following categories of clinical outcomes were performed: fracture (n = 40, assessed in one study), mortality (n = 18), function (n = 11), institutionalization (n = 7), falls (n = 4), and hospitalization (n = 2). Thereby, EWGSOP2 was investigated in 15 validity tests (18.3%) on all categories of clinical outcomes, whereas SDOC was investigated in four validity tests (4.9%) in one study on fractures in men only, and none of the validity tests investigated predictive validity by the AWGS2. However, we were not able to pool the data using a meta‐analytic approach due to important methodological heterogeneity between the studies. We identified various definitions of clinical outcomes that were used to test predictive validity of sarcopenia definitions suggesting that an agreement on an operational definition of a clinical outcome is key to advance in the field of sarcopenia. Moreover, data on predictive validity using the sarcopenia definitions by the SDOC and AWGS2 are still scarce and lacking, respectively. In a next step, prospective studies including both women and men are needed to compare predictive validity of current sarcopenia definitions on defined key clinical outcomes.

Background: The European Working Group on Sarcopenia has recently proposed revised cut-off values for the definition of low grip strength (EWGSOP2). We therefore compared performance of the EWGSOP2 cut-off definition of low grip strength with other internationally used cut-off points in a sample of older patients. Methods: We analyzed geriatric assessment data in a cross-sectional sample of 98 older patients admitted to a post-acute care hospital. First, we compared prevalence of sarcopenia and frailty phenotype in our sample using low grip strength cut-points from the EWGSOP2 and seven other internationally used consensus statements. Second, we calculated correlations between low grip strength and two independent surrogate outcomes (i.e., gait speed, and the clinical frailty scale) for the EWGSOP2 and the other seven cut-point definitions. Results: Prevalence of sarcopenia based on the EWGSOP2 grip strength cut-off values was significantly lower (10.2%) than five of the seven other cut-point definitions (e.g., 19.4% based on Sarcopenia Definitions and Outcomes Consortium (SDOC) criteria). Similarly, frailty phenotype prevalence was significantly lower based on EWGSOP2 cut-points (57.1%) as compared to SDOC (70.4%). The correlation coefficient of gait speed with low grip strength based on EWGSOP2 cut-points was lower (0.145) as compared to other criteria (e.g., SDOC 0.240). Conclusions: Sarcopenia and frailty phenotype were identified considerably less using the EWGSOP2 cut-points for low grip strength, potentially underestimating prevalence of sarcopenia and frailty phenotype in post-acute hospital patients.

Purpose: Muscle ultrasound has emerged as a promising method in the diagnostic work-up of sarcopenia. The objective of this scoping review was to explore the validity of muscle ultrasound against the latest sarcopenia definitions among older adults. Methods: We adhered to the PRISMA guidelines for scoping reviews. A systematic search of databases was performed by two independent reviewers. All articles comparing the performance of ultrasound to an internationally acknowledged sarcopenia definition among older adults (≥ 60 years) and published between 2019/01/01 (the year updated sarcopenia definitions were introduced) and 2023/11/15 were included. Data were extracted and collated by muscle and muscle parameters. Results: Out of 2290 articles screened, six studies comprising 24 validity tests among a total of 1619 older adults (mean age 74.1 years, 52.2% female) were included. The validity tests investigated the rectus femoris (n = 7), biceps brachii (n = 5), gastrocnemius medialis (n = 4), tibialis anterior (n = 4), soleus (n = 3), and rectus abdominis (n = 1). The parameter muscle thickness (MT) (n = 14) was most commonly measured. The latest European and Asian sarcopenia definitions (EWGSOP2, AWGS2) were applied as reference standards in four validity tests each. None of the studies used the Sarcopenia Definition and Outcome Consortium (SDOC) criteria. The highest area under the curve AUC (0.92, 95% confidence interval [CI] 0.89– 0.94) was found for the muscle thickness of the rectus femoris muscle. Due to substantial heterogeneity among the studies, pooling of data using a meta-analytic approach was not feasible. Conclusion: Limited number of studies have examined the validity of muscle ultrasound for diagnosing sarcopenia based on recent definitions among older adults. Thereby, muscle thickness of the rectus femoris showed promising results regarding validity. Further studies are needed to investigate the validity of key muscles and to validate muscle ultrasound among older hospitalized patients.

Objectives To evaluate the ability of 3 commonly used frailty measures to predict short-term clinical outcomes in older patients admitted for post-acute inpatient rehabilitation. Design Observational cohort study. Setting and Participants Consecutive patients (n = 207) admitted to a geriatric inpatient rehabilitation facility. Methods Frailty on admission was assessed using a frailty index, the physical frailty phenotype, and the Clinical Frailty Scale (CFS). Predictive capacity of the frailty instruments was analyzed for (1) nonhome discharge, (2) readmission to acute care, (3) functional decline, and (4) prolonged length of stay, using multivariate logistic regression models and receiver operating characteristic (ROC) curves. Results The number of patients classified as frail was 91 (44.0%) with the frailty index, 134 (64.7%) using the frailty phenotype, and 151 (73.0%) with the CFS. The 3 frailty measures revealed acceptable discriminatory accuracy for nonhome discharge (area under the curve ≥ 0.7) but differed in their predictive ability: the adjusted odds ratio (OR) for nonhome discharge was highest for the CFS [6.2, 95% confidence interval (CI) 1.8-21.1], compared to the frailty index (4.1, 95% CI 2.0-8.4) and the frailty phenotype (OR 2.9, 95% CI 1.2-6.6). For the other outcomes, discriminatory accuracy based on ROC tended to be lower and predictive ability varied according to frailty measure. Readmission to acute care from inpatient rehabilitation was predicted by all instruments, most pronounced by the frailty phenotype (OR 5.4, 95% CI 1.6-18.8) and the frailty index (OR 2.5, 95% CI 1.1-5.6), and less so by the CFS (OR 1.4, 95% CI 0.5-3.8). Conclusions and Implications Frailty measures may contribute to improved prediction of outcomes in geriatric inpatient rehabilitation. The choice of the instrument may depend on the individual outcome of interest and the corresponding discriminatory ability of the frailty measure.