Comparison of a Multi-Component Physical Function Battery to Usual Walking Speed for Assessing Lower Extremity Function and Mobility Limitation in Older Adults

A systematic review of the psychometric properties of physical performance tests for sarcopenia in community-dwelling older adults

BACKGROUND

This review provides an overview of the psychometric properties of the short physical performance battery (SPPB), timed up and go test (TUG), 4 m gait speed test (4 m GST) and the 400 m walk test (400 m WT) in community-dwelling older adults.

METHODS

A systematic search was conducted in MEDLINE, CINAHL and EMBASE, resulting in the inclusion of 50 studies with data from in total 19,266 participants (mean age 63.2-84.3). Data were extracted and properties were given a sufficient or insufficient overall rating following the COSMIN guideline for systematic reviews of patient-reported outcome measures. Quality of evidence (QoE) was rated using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

RESULTS

The SPPB was evaluated in 12 studies, TUG in 30, 4 m GST in 12 and 400 m WT in 2. Reliability of the SPPB, TUG and 4 m GST was rated sufficient (moderate to good QoE). The measurement error of the SPPB was rated insufficient (low QoE). Criterion validity for the SPPB was insufficient in indicating sarcopenia (moderate QoE), while the TUG was sufficient and insufficient for determining mobility limitations (low QoE) and activities of daily living disability (low QoE), respectively. Construct validity of the SPPB, TUG, 4 m GST and 400 m WT was rated insufficient in many constructs (moderate to high QoE). Responsiveness was rated as insufficient for SPPB (high QoE) and TUG (very low QoE), while 4 m GST was rated as sufficient (high QoE).

CONCLUSION

Overall, the psychometric quality of commonly used physical performance tests in community-dwelling older adults was generally rated insufficient, except for reliability. These tests are widely used in daily practice and recommended in guidelines; however, users should be cautious when drawing conclusions such as sarcopenia severity and change in physical performance due to limited psychometric quality of the recommended measurement instruments. There is a need for a disease-specific physical performance test for people with sarcopenia.This research received no specific grant from any funding agency and was registered a priori using the International Prospective Register of Systematic Reviews (PROSPERO) (CRD42022359725).

Measurement properties of the usual and fast gait speed tests in community-dwelling older adults: a COSMIN-based systematic review

OBJECTIVE

The gait speed test is one of the most widely used mobility assessments for older adults. We conducted a systematic review to evaluate and compare the measurement properties of the usual and fast gait speed tests in community-dwelling older adults.

METHODS

Three databases were searched: MEDLINE, EMBASE and CINAHL. Peer-reviewed articles evaluating the gait speed test's measurement properties or interpretability in community-dwelling older adults were included. The Consensus-based Standards for the selection of health Measurement Instruments guidelines were followed for data synthesis and quality assessment.

RESULTS

Ninety-five articles met our inclusion criteria, with 79 evaluating a measurement property and 16 reporting on interpretability. There was sufficient reliability for both tests, with intraclass correlation coefficients (ICC) generally ranging from 0.72 to 0.98, but overall quality of evidence was low. For convergent/discriminant validity, an overall sufficient rating with moderate quality of evidence was found for both tests. Concurrent validity of the usual gait speed test was sufficient (ICCs = 0.79-0.93 with longer distances) with moderate quality of evidence; however, there were insufficient results for the fast gait speed test (e.g. low agreement with longer distances) supported by high-quality studies. Responsiveness was only evaluated in three articles, with low quality of evidence.

CONCLUSION

Findings from this review demonstrated evidence in support of the reliability and validity of the usual and fast gait speed tests in community-dwelling older adults. However, future validation studies should employ rigorous methodology and evaluate the tests' responsiveness.

Estimating cutpoints of gait speed and sit-to-stand test values for self-reported mobility limitations in a cohort of community-dwelling older adults from Singapore: comparing receiver operating characteristic (ROC) analysis with adjusted predictive modelling

OBJECTIVES

Clinical interpretability of the gait speed and 5-times sit-to-stand (5-STS) tests is commonly established by comparing older adults with and without self-reported mobility limitations (SRML) on gait speed and 5-STS performance, and estimating clinical cutpoints for SRML using the receiver operating characteristics (ROC) method. Accumulating evidence, however, suggests that the adjusted predictive modeling (APM) method may be more appropriate to estimate these interpretational cutpoints. Thus, we aimed to compare, in community-dwelling older adults, gait speed and 5-STS cutpoints estimated using the ROC and APM methods.

DESIGN

Cross-sectional study.

SETTING AND PARTICIPANTS

This study analyzed data from 955 community-dwelling independently walking older adults (73%women) aged ≥60 years (mean, 68; range, 60-88).

METHODS

Participants completed the 10-metre gait speed and 5-STS tests. Participants were classified as having SRML if they responded "Yes" to either of the 2 questions regarding walking and stair climbing difficulty. Cutpoints for SRML and its component questions were estimated using ROC analysis with Youden criterion and the APM method.

RESULTS

The proportions of participants with self-reported walking difficulty, self-reported stair climbing difficulty, and SRML were 10%, 19%, and 22%, respectively. Gait speed and 5-STS time were moderately correlated with each other (r=-0.56) and with the self-reported measures (absolute r-values, 0.39-0.44). ROC-based gait speed cutpoints were 0.14 to 0.16 m/s greater than APM-based cutpoints (P < 0.05) whilst ROC-based 5-STS time cutpoints were 0.8 to 3.3 s lower than APM-based cutpoints (P < 0.05 for walking difficulty). Compared with ROC-based cutpoints, APM-based cutptoints were more precise and they varied monotonically with self-reported walking difficulty, self-reported stair climbing difficulty, and SRML.

CONCLUSIONS AND IMPLICATIONS

In a sample of 955 older adults, our findings of precise and biologically plausible gait speed and 5-STS cutpoints for SRML estimated using the APM method indicate that this promising method could potentially complement or even replace traditional ROC methods.

Hand Grip Strength Relative to Waist Circumference as a Means to Identify Men and Women Possessing Intact Mobility in a Cohort of Older Adults with Type 2 Diabetes

Possessing intact mobility in older adults assures their continued independence. The early identification of reduced mobility in older adults with type 2 diabetes (T2DM) is paramount for preventing their future physical deterioration. Hand grip strength (HGS), relative to body size, is associated with mobility in older T2DM patients. This study aims to identify an HGS index that best identifies mobilityintact older T2DM patients, along with its optimal cut-off point. The baseline data are from a cohort of 122 older T2DM patients (59% women) (mean age of 70.2 ± 4.4 years). Three mobility tests encompassing three main mobility domains were measured, including usual gait speed (UGS), timed up and go (TUG), and a two-minute walk test (2MWT). Passing scores were defined as those either above the established cut-off points or above the 25th percentile of population norms. Passing all three tests was considered as possessing intact mobility. Receiver operating characteristic (ROC) curves of the most relevant HGS indices were constructed to determine the area under the curve (AUC) that best identifies patients with intact mobility. In a sample of 122 older adults with T2DM, 63.9% of women and 60% of men were found to possess intact mobility. HGS relative to waist circumference (WC) was found to have the strongest association with intact mobility, presenting the highest AUC in both men (0.78) and women (0.72) for discriminating mobility status, with an optimal cut-off of 0.355 (kg/cm) and 0.245 (kg/cm) in men and women, respectively. HGS relative to WC best differentiated between mobility-intact older adults with T2DM and those with mobility limitations, especially in men. Using HGS/WC as a simple and safe screening mode for mobility in a clinical setting could potentially identify older patients with T2DM that require therapeutic interventions.

Brain-Predicted Age Difference Moderates the Association Between Muscle Strength and Mobility

Background

Approximately 35% of individuals over age 70 report difficulty with mobility. Muscle weakness has been demonstrated to be one contributor to mobility limitations in older adults. The purpose of this study was to examine the moderating effect of brain-predicted age difference (an index of biological brain age/health derived from structural neuroimaging) on the relationship between leg strength and mobility.

Methods

In community dwelling older adults (N = 57, 74.7 ± 6.93 years; 68% women), we assessed the relationship between isokinetic leg extensor strength and a composite measure of mobility [mobility battery assessment (MBA)] using partial Pearson correlations and multifactorial regression modeling. Brain predicted age (BPA) was calculated from T1 MR-images using a validated machine learning Gaussian Process regression model to explore the moderating effect of BPA difference (BPAD; BPA minus chronological age).

Results

Leg strength was significantly correlated with BPAD (r = −0.317, p < 0.05) and MBA score (r = 0.541, p < 0.001). Chronological age, sex, leg strength, and BPAD explained 63% of the variance in MBA performance (p < 0.001). BPAD was a significant moderator of the relationship between strength and MBA, accounting for 7.0% of MBA score variance [△R² = 0.044, F(1,51) = 6.83, p = 0.01]. Conditional moderation effects of BPAD indicate strength was a stronger predictor of mobility in those with a great BPAD.

Conclusion

The relationship between strength and mobility appears to be influenced by brain aging, with strength serving as a possible compensation for decline in neural integrity.

Sarcopenia Assessment Techniques

Content available: Author Audio Recording.

Heterogeneity of the strength response to progressive resistance exercise training in older adults: Contributions of muscle contractility

BACKGROUND

Older adults display wide individual variability (heterogeneity) in the effects of resistance exercise training on muscle strength. The mechanisms driving this heterogeneity are poorly understood. Understanding of these mechanisms could permit development of more targeted interventions and/or improved identification of individuals likely to respond to resistance training interventions. Thus, this study assessed potential physiological factors that may contribute to strength response heterogeneity in older adults: neural activation, muscle hypertrophy, and muscle contractility.

METHODS

In 24 older adults (72.3 ± 6.8 years), we measured the following parameters before and after 12 weeks of progressive resistance exercise training: i) isometric leg extensor strength; ii) isokinetic (60°/sec) leg extensor strength; iii) voluntary (neural) activation by comparing voluntary and electrically-stimulated muscle forces (i.e., superimposed doublet technique); iv) muscle hypertrophy via dual-energy x-ray absorptiometry (DXA) estimates of regional lean tissue mass; and v) intrinsic contractility by electrically-elicited twitch and doublet torques. We examined associations between physiological factors (baseline values and relative change) and the relative change in isometric and isokinetic muscle strength.

RESULTS

Notably, changes in quadriceps contractility were positively associated with the relative improvement in isokinetic (r = 0.37-0.46, p ≤ 0.05), but not isometric strength (r = 0.09-0.21). Change in voluntary activation did not exhibit a significant association with the relative improvements in either isometric or isokinetic strength (r = 0.35 and 0.33, respectively; p > 0.05). Additionally, change in thigh lean mass was not significantly associated with relative improvement in isometric or isokinetic strength (r = 0.09 and -0.02, respectively; p > 0.05). Somewhat surprising was the lack of association between exercise-induced changes in isometric and isokinetic strength (r = 0.07).

CONCLUSIONS

The strength response to resistance exercise in older adults appears to be contraction-type dependent. Therefore, future investigations should consider obtaining multiple measures of muscle strength to ensure that strength adaptations are comprehensively assessed. Changes in lean mass did not explain the heterogeneity in strength response for either contraction type, and the data regarding the influence of voluntary activation was inconclusive. For isokinetic contraction, the strength response was moderately explained by between-subject variance in the resistance-exercise induced changes in muscle contractility.

The SARC-F Score on Admission Predicts Falls during Hospitalization in Older Adults

OBJECTIVES

Community-dwelling older adults with sarcopenia are likely to fall. However, few studies have investigated whether sarcopenia is associated with falls during hospitalization in older adults. The purpose of this study was to determine whether the SARC-F when used as a simple screening tool for sarcopenia at the time of admission, predicts in-hospital falls.

DESIGN

A retrospective, observational study.

SETTING

A 900-bed university hospital.

PARTICIPANTS

A total of 9,927 patients aged 65 years and older were hospitalized at the hospital between April 2019 and March 2020.

MEASUREMENTS

The SARC-F contains five items: strength, assistance in walking, rise from a chair, climb stairs, and falls were evaluated at hospital admission. To investigate the relationship between the SARC-F score and falls, a ROC curve analysis was performed. Multivariate analysis adjusted for fall-related confounding factors such as age, gender, ADL, and disease were performed.

RESULTS

Mean age: 75.9±6.7 years; male: 56.2% were analyzed, and 159 patients (1.6%) fell during hospitalization. SARC-F scores at admission were significantly higher in the fall group than in the control group (3 [1-6] points vs. 0 [¬0-2] point, p<0.001). Statistical association was observed between the SARC-F and in-hospital fall (area under the curve = 0.721 [0.678-0.764], p < 0.001). The cut-off value for the highest sensitivity and specificity of the SARC-F score for in-hospital falls was two (sensitivity = 0.679, specificity = 0.715). Among the subitem of the SARC-F, the hazard ratios for climbing stairs were significantly higher (HR = 1.52 [1.10-2.09], p = 0.011) and for a history of fall was significantly higher (HR = 1.41 [1.02-1.95], p = 0.036). A SARC-F score ≥ 2 had a significantly higher incidence of in-hospital falls compared to a SARC-F score <2 (3.7% vs. 0.7%, p < 0.001). Also, a SARC-F score ≥ 2 had a significantly higher hazard ratio for falls (2.11 [1.37-3.26], p < 0.001).

CONCLUSION

SARC-F can help predict falls among hospitalized older adults.