Application of Cut-Points for Low Muscle Strength and Lean Mass in Mobility-Limited Older Adults

Can EWGSOP2 and SDOC Definitions of Sarcopenia Identify Functional Muscle Quality?

Objectives

To compare the European Working Group on Sarcopenia in Older People (EWGSOP2) and the Sarcopenia Definition and Outcomes Consortium (SDOC) in identifying muscle quality indexes (MQI) and lower limb muscle performance in older women aged ≥ 65.

Methods

Participants meeting EWGSOP2 and SDOC criteria were classified into the sarcopenia group (GS); others were placed in the non-sarcopenia group (GNS). Using an isokinetic dynamometer, we assessed peak torque (PT), maximal work (MW), and power (POW) of lower limbs. MQI was calculated as the ratio of muscle performance to appendicular lean mass, adjusted for body mass index (BMI) and lean tissue mass of the right lower limb (LTM).

Results

We included 96 older women. In both SDOC (n=37) and EWGSOP2 (n=48) sarcopenia groups, muscle performance and BMI-adjusted MQI were significantly lower. Sarcopenia (SDOC) was significantly associated with all lower limb muscle performance and MQI variables [adjusted model by age and race: MQIPOW/LTM OR = 0.67 (95% CI 0.52; 0.85); MQIPT/LTM OR = 0.76 (95% CI 0.64; 0.89)].

Conclusions

Older women diagnosed with sarcopenia by EWGSOP2 and SDOC criteria showed significant declines in muscle function and quality. The SDOC definition discriminated muscle contraction quality components in older individuals with and without sarcopenia.

Prevalence and impact of sarcopenia in individuals with heart failure with reduced ejection fraction (the SARC-HF study): A prospective observational study protocol

Sarcopenia, a clinical syndrome primarily associated with reduced muscle mass in the elderly, has a negative impact on quality of life and survival. It can occur secondarily to other diseases such as heart failure (HF), a complex clinical syndrome with high morbidity and mortality. The simultaneous occurrence of these two conditions can worsen the prognosis of their carriers, especially in the most severe cases of HF, as in patients with reduced left ventricular ejection fraction (LVEF). However, due to the heterogeneous diagnostic criteria for sarcopenia, estimates of its prevalence present a wide variation, leading to new criteria having been recently proposed for its diagnosis, emphasizing muscle strength and function rather than skeletal muscle mass. The primary objective of this study is to evaluate the prevalence of sarcopenia and/or dynapenia in individuals with HF with reduced LVEF according to the most recent criteria, and compare the gene and protein expression of those patients with and without sarcopenia. The secondary objectives are to evaluate the association of sarcopenia and/or dynapenia with the risk of clinical events and death, quality of life, cardiorespiratory capacity, ventilatory efficiency, and respiratory muscle strength. The participants will answer questionnaires to evaluate sarcopenia and quality of life, and will undergo the following tests: handgrip strength, gait speed, dual-energy X-ray absorptiometry, respiratory muscle strength, cardiopulmonary exercise, as well as genomic and proteomic analysis, and dosage of N-terminal pro-B-type natriuretic peptide and growth differentiation factor-15. An association between sarcopenia and/or dynapenia with unfavorable clinical evolution is expected to be found, in addition to reduced quality of life, cardiorespiratory capacity, ventilatory efficiency, and respiratory muscle strength.

Sarcopenia Definition Outcome Consortium - defined Weakness and Risk of Falls: The National Health and Aging Trends Survey

AIM

The prevalence of obesity continues to rise, as does that of weakness. However, it is unclear how this impacts the risk of falling. We aimed to ascertain the risk of falls using new definitions of clinically defined weakness.

METHODS

We applied clinically defined weakness definitions to the National Health and Aging Trends Survey using the Sarcopenia Definitions Outcomes Consortium cutpoints. Three exposure variables were created: grip-strength-defined weakness and body mass index [GS/BMI]-defined obesity; weakness and obesity, weakness and waist circumference-derived obesity (GS/WC); and weakness defined by a ratio of GS÷BMI. Proportional hazards modeled incident falls as a function of weakness with/without obesity (hazard ratio [HR] [95% confidence intervals]).

RESULTS

Of 4906 respondents aged ≥ 65 years (54.5% female), the mean ± SD grip strength, BMI, and WC were 26.7 ± 10.6 kg, 27.4 ± 5.4 kg/m2 , and 99.5 ± 16.3 cm, respectively. Using the neither weakness/obesity as the referent, weakness was associated with incident falls across all definitions (GS/BMI: HR 1.19 [1.07, 1.33]; GS/WC: HR 1.39 [1.19, 1.62]; GS ÷ BMI: HR 1.16 [1.05, 1.28]). Weakness with obesity was associated with falls using GS/WC (HR 1.28 [1.11, 1.48]). Obesity status was associated with falls in both the BMI and the WC definition (1.17 [1.02-1.35], 1.16 [1.05-1.28]).

CONCLUSION

Our findings further evaluate the definitions of clinically defined weakness with and without obesity in older adults. As falls are an important patient outcome, establishing this relationship is critical for both clinicians and researchers. Future study should identify high-risk individuals in order to direct specific interventions to them. Geriatr Gerontol Int 2023; 23: 213-220.

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.

Influenza infection is not associated with phenotypical frailty in older patients, a prospective cohort study

Background and Aims

Influenza is a challenging infectious illness for older adults. It is not completely clear whether influenza is associated with frailty or functional decline. We sought to determine the association between incident influenza infection and frailty and prefrailty in community patients over 50 years of age. We also investigated the association between influenza vaccination and frailty and prefrailty as a secondary aim.

Methods

This was a prospective community cohort study from October 2019 to November 2020 in participants over 50 years. The primary outcome was the development of frailty as defined by three of five frailty criteria (slow gait speed, low grip strength, 5% weight loss, low energy, and low physical functioning). The primary predictor was a positive polymerase chain reaction (PCR) for influenza infection. Influenza vaccination was based on electronic health record reviewing 1 year before enrollment. We reported the relationship between influenza and frailty by calculating odds ratios (OR) with 95% confidence intervals (CI) after adjustment for age, sex, socioeconomic status, Charlson Comorbidity Index (CCI), influenza vaccine, and previous self-rated frailty from multinomial logistic regression model comparing frail and prefrail to nonfrail subjects.

Results

In 1135 participants, the median age was 67 years (interquartile range  60-74), with 41% men. Eighty-one participants had PCR-confirmed influenza (7.1%). Frailty was not associated with influenza, with an OR of 0.50 (95% CI 0.17-1.43) for frail participants compared to nonfrail participants. Influenza vaccination is associated with frailty, with an OR of 1.69 (95% CI 1.09-2.63) for frail compared to nonfrail. Frailty was associated with a higher CCI with an OR of 1.52 (95% CI 1.31-1.76).

Conclusion

We did not find a relationship between influenza infection and frailty. We found higher vaccination rates in participants with frailty compared to nonfrail participants While influenza was not associated with frailty, future work may involve longer follow-up.

Associations of components of sarcopenia with risk of fracture in the Osteoporotic Fractures in Men (MrOS) study

Our aim was to evaluate the associations between the individual components of sarcopenia and fracture types. In this cohort, the risk of experiencing any clinical, hip, or major osteoporotic fracture is greater in men with slow walking speed in comparison to normal walking speed.

INTRODUCTION

The association between the components of sarcopenia and fractures has not been clearly elucidated and has hindered the development of appropriate therapeutic interventions. Our aim was to evaluate the associations between the individual components of sarcopenia, specifically lean mass, strength, and physical performance and fracture (any fracture, hip fracture, major osteoporotic fracture) in the Osteoporotic Fractures in Men (MrOS) study.

METHODS

The Osteoporotic Fractures in Men study (MrOS) recruited 5995 men ≥ 65 years of age. We measured appendicular lean mass (ALM) by dual-energy X-ray absorptiometry (low as residual value < 20th percentile for the cohort), walking speed (fastest trial of usual pace, values < 0.8 m/s were low), and grip strength (max score of 2 trials, values < 30 kg were low). Information on fractures was assessed tri-annually over an average follow-up of 12 years and centrally adjudicated. Cox proportional hazard models estimated the hazard ratio (HR) (95% confidence intervals) for slow walking speed, low grip strength, and low lean mass.

RESULTS

Overall, 1413 men had a fracture during follow-up. Slow walking speed was associated with an increased risk for any HR = 1.39, 1.05-1.84; hip HR = 2.37, 1.54-3.63; and major osteoporotic, HR = 1.89, 1.34-2.67 in multi-variate-adjusted models. Low lean mass and low grip strength were not significantly associated with fracture.

CONCLUSIONS

In this cohort of older adult men, the risk of experiencing any, hip, or major osteoporotic fracture is greater in men with slow walking speed in comparison to men with normal walking speed, but low grip strength and low lean mass were not associated with fracture.

Muscle Weakness and Walking Slowness for the Identification of Sarcopenia in the Older Adults from Northern Brazil: A Cross-Sectional Study

Background: This study aimed to analyze the prevalence of sarcopenia in elderly people from Northern Brazil according to muscle weakness or walking slowness. Methods: The sample consisted of 312 elderly people (72.6 ± 7.8 years). For walking slowness, a gait speed ≤ 0.8 m/s was used as a cut-off value, and for muscle weakness the following handgrip strength criteria were used for men and women, respectively: CI: <27.0/16.0 kg; CII: <35.5/20.0 kg; CIII: grip strength corrected for body mass index (BMI) < 1.05/0.79; CIV: grip strength corrected for total fat mass: <1.66/0.65; CV: grip strength corrected for body mass: <0.45/0.34. Results: Walking speed was reduced in 27.0% of women and 15.2% of men (p < 0.05). According to grip strength criteria, 28.5% of women and 30.4% of men (CI), 58.0% of women and 75.0% of men (CII), 66.0% of women and 39.3% of men (CIII), 28.8% of women and 19.6% of men (CIV), and 56.5% of women and 50.0% of men (CV) were identified as having sarcopenia. Conclusions: Walking slowness is more prevalent in women and muscle weakness is more prevalent in men in Northern Brazil. Walking slowness proved to be more concordant with muscle weakness in both sexes when the CI for handgrip strength was adopted.

Sarcopenia definition: Does it really matter? Implications for resistance training

The loss of muscle mass, strength and function, known as sarcopenia, is common in older adults, and is associated with falls, fractures, cardiometabolic diseases, and lower quality of life. Sarcopenia can also occur secondarily to chronic diseases. Recently, sarcopenia was recognized as a disease with an International Classification of Disease (ICD) code, yet, at least five definitions for its clinical identification exist. Most definitions include three themes: low muscle mass, strength and physical performance. However, the definitions vary by the number of themes needed to diagnose sarcopenia and, within each theme various parameters and cut-off levels exist. The lack of consensus on what constitutes a diagnosis can create confusion and hesitation in sarcopenia diagnosis. Currently, no pharmacological treatment exists for sarcopenia. Resistance training (RT) is safe and effective to improve muscle mass, strength and physical performance in older adults and clinical populations. Based on current guidelines, whether an individual is defined as "sarcopenic", or not, does not change the way RT is prescribed. Here, we present evidence and the inconsistencies in sarcopenia definitions and recommend that focus should be on optimizing ways to prescribe RT and increase long-term adherence, rather than on slight modifications to sarcopenia definitions.

Prognostic utility of self-reported sarcopenia (SARC-F) in the Multiethnic Cohort

BACKGROUND

Age-related loss in skeletal muscle mass, quality, and strength, known as sarcopenia, is a well-known phenomenon of aging and is determined clinically using methods such as dual-energy X-ray absorptiometry (DXA). However, these clinical methods to measure sarcopenia are not practical for population-based studies, and a five-question screening tool known as SARC-F has been validated to screen for sarcopenia.

METHODS

We investigated the relationship between appendicular skeletal lean mass/height² (ALM/HT² ) (kg/m² ) assessed by DXA and SARC-F in a subset of 1538 (778 men and 760 women) participants in the Multiethnic Cohort (MEC) Study after adjustment for race/ethnicity, age, and body mass index (BMI) at the time of DXA measurement. We then investigated the association between SARC-F and mortality among 71 283 (41 757 women and 29 526 men) participants in the MEC, who responded to the five SARC-F questions on a mailed questionnaire as part of the MEC follow-up in 2012-2016.

RESULTS

In women, SARC-F score was significantly inversely associated with ALM/HT² after adjusting for race/ethnicity, and age and BMI at DXA (r = -0.167, P < 0.001); the result was similar in men although it did not reach statistical significance (r = -0.056, P = 0.12). Among the 71 000+ MEC participants, SARC-F score ≥ 4, as an indicator of sarcopenia, was higher in women (20.9%) than in men (11.2%) (P < 0.0001) and increased steadily with increasing age (6.3% in <70 vs. 41.3% in 90+ years old) (P < 0.0001). SARC-F score ≥ 4 was highest among Latinos (30.8% in women and 16.1% in men) and lowest in Native Hawaiian women (15.6%) and Japanese American men (8.9%). During an average of 6.8 years of follow-up, compared with men with SARC-F score of 0-1 (indicator of no sarcopenia), men with SARC-F 2-3 (indicator of pre-sarcopenia) and SARC-F ≥ 4 had significantly increased risk of all-cause mortality [hazard ratio (HR) = 1.00, 1.77, 3.73, P < 0.001], cardiovascular disease (CVD) mortality (HR = 1.00, 1.85, 3.98, P < 0.001), and cancer mortality (HR = 1.00, 1.46, 1.96, P < 0.001) after covariate adjustment. Comparable risk association patterns with SARC-F scores were observed in women (all-cause mortality: HR = 1.00, 1.47, 3.10, P < 0.001; CVD mortality: HR = 1.00, 1.59, 3.54, P < 0.001; cancer mortality: HR = 1.00, 1.30, 1.77, P < 0.001). These significant risk patterns between SARC-F and all-cause mortality were found across all sex-race/ethnic groups considered (12 in total).

CONCLUSIONS

An indicator of sarcopenia, determined using SARC-F, showed internal validity against DXA and displayed racial/ethnic and sex differences in distribution. SARC-F was associated with all-cause mortality as well as cause-specific mortality.

The Association Between Walking Speed and Bone Turnover Markers in Older Adults

Background  Previous research conducted among institutionalized older adults has reported increased bone turnover markers (BTMs) in those subjects with mobility limitation. However, the association between walking speed and bone metabolism has not been well described in community-dwelling older adults. Methods The National Health and Nutrition Examination Survey 1999-2000 and 2001-2002 cycles were used to determine the association between the 20-feet walking speed test and bone alkaline phosphatase (BAP) and the cross-linked N-telopeptides of type I bone collagen (NTx). Sex-specific general linear models adjusted for potential confounders were assembled to examine the independent association between the time to complete the walking speed test grouped into quartiles and the logarithmic transformations of BAP and NTx levels.  Results Of 2,521 older adults, 25.8% were defined as having mobility limitation. In both genders, BTM levels progressively increased as the time to complete the walking test also increase. Indeed, women and men who completed the walking speed test in the worst time quartile had on average 6% and 2.8% higher NTx levels than their counterparts who completed the test in the best time quartile, respectively. Likewise, BAP levels also progressively increased across walking speed time quartiles, but to a lesser degree. Notably, NTx levels were 4.7% and 2.6% higher in women and men with mobility limitation than those without, respectively. In contrast, BAP levels did not significantly differ in older adults regardless of their mobility limitation status. Conclusions Community-dwelling older adults with slower walking speeds and mobility limitation consistently had evidence of increased bone resorption. Thus, the present findings indicate that older adults with mobility limitation should be considered at risk of osteoporosis.

Implications of Race and Ethnicity in Sarcopenia US National Prevalence of Sarcopenia by Muscle Mass, Strength, and Function Indices

Sarcopenia prevalence varies widely by definitions and populations, which led to the creation of new criteria by the Sarcopenia Definitions and Outcomes Consortium. Yet, the degree to which sarcopenia prevalence varies according to these criteria across race and ethnic groups in the U.S. population needs further investigation. We estimated the US national prevalence of sarcopenia using different indices among adults aged 50-80 years across race and ethnicity groups utilizing data from the National Health and Nutrition Examination Surveys (NHANES: 1999-2002 and 2011-2014). Sarcopenia was defined by appendicular lean mass divided by body mass index (ALM/BMI), grip strength, and gait speed. For each index the following samples were constructed: grip strength (NHANES 2011-2014: N=4,615), gait speed (NHANES 1999-2002: N=3,448) and ALM/BMI (NHANES 1999-2002: N=3,448) among adults aged 50-80 years. Sarcopenia prevalence varied by race/ethnicity: NH-Whites (11.2-24.3%), Hispanics (21.9-36.0%), NH-Blacks (4.4-27.7%), and Asians/others (18.5-35.7%). Based on the multivariable models, compared to NH-Whites, NH-Blacks were less likely to have sarcopenia by ALM/BMI (OR=0.26, 95%CI: 0.18-0.39), and more likely by gait speed (OR=3.90, 95% CI: 3.00-5.06) with no difference by grip strength (OR=0.96, 95%CI: 0.75-1.24). While, Hispanics and Asians/others were more likely to have sarcopenia by grip strength, gait speed, and ALM/BMI (ORs=2.15-3.21) compared to NH-Whites. This study suggests the need for inclusion of race/ethnicity related criteria in sarcopenia definitions. Future investigations could determine whether this discrepancy between race/ethnicity across sarcopenia indices, particularly in NH-Blacks, is partly due to either muscle mass or functional changes with aging.

Barriers to eating are associated with poor physical function in older women

Older adults have physical and social barriers to eating but whether this affects functional status is unknown. We examined associations between eating barriers and physical function in the Women's Health Initiative (WHI). In 2012-14, a subset of alive and participating women (n = 5910) completed an in-home examination including the Short Physical Performance Battery (SPPB) (grip strength, balance, timed walking speed, chair stand). WHI participants complete annual mailed questionnaires; the 2013-14 questionnaire included items on eating alone, eating < two meals/day, dentition problems affecting eating, physical difficulties with cooking/shopping and monetary resources for food. Linear regression tested associations of these eating barriers with SPPB, adjusting for BMI, age, race/ethnicity, and medical multimorbidities. Over half (56.8%) of participants were ≥ 75 years, 98.8% had a BMI ≥ 25.0 kg/m2 and 66% had multimorbidities. Eating barriers, excluding eating alone, were associated with significantly lower total (all p < .001) and component-specific, multivariate-adjusted SPPB scores (all p < .05). Compared to no barriers, eating < two meals/day (7.83 vs. 8.38, p < .0002), dentition problems (7.69 vs. 8.38, p < .0001), inability to shop/prepare meals (7.74 vs. 8.38, p < .0001) and insufficient resources (7.84 vs. 8.37 p < .001) were significantly associated with multivariate-adjusted mean SPPB score < 8. Models additionally adjusting for Healthy Eating Index-2010 had little influence on scores. As barriers increased, scores declined further for grip strength (16.10 kg for 4-5 barriers, p = .001), timed walk (0.58 m/s for 4-5 barriers, p = .001) and total SPPB (7.27 for 4-5 barriers, p < .0001). In conclusion, in this WHI subset, eating barriers were associated with poor SPPB scores.

Putative Cut-Points in Sarcopenia Components and Incident Adverse Health Outcomes: An SDOC Analysis

OBJECTIVES

Analyses performed by the Sarcopenia Definitions and Outcomes Consortium (SDOC) identified cut-points in several metrics of grip strength for consideration in a definition of sarcopenia. We describe the associations between the SDOC-identified metrics of low grip strength (absolute or standardized to body size/composition); low dual-energy x-ray absorptiometry (DXA) lean mass as previously defined in the literature (appendicular lean mass [ALM]/ht2 ); and slowness (walking speed <.8 m/s) with subsequent adverse outcomes (falls, hip fractures, mobility limitation, and mortality).

DESIGN

Individual-level, sex-stratified pooled analysis. We calculated odds ratios (ORs) or hazard ratios (HRs) for incident falls, mobility limitation, hip fractures, and mortality. Follow-up time ranged from 1 year for falls to 8.8 ± 2.3 years for mortality.

SETTING

Eight prospective observational cohort studies.

PARTICIPANTS

A total of 13,421 community-dwelling men and 4,828 community-dwelling women. MEASUREMENTS Grip strength by hand dynamometry, gait speed, and lean mass by DXA.

RESULTS

Low grip strength (absolute or standardized to body size/composition) was associated with incident outcomes, usually independently of slowness, in both men and women. ORs and HRs generally ranged from 1.2 to 3.0 for those below vs above the cut-point. DXA lean mass was not consistently associated with these outcomes. When considered together, those who had both muscle weakness by absolute grip strength (<35.5 kg in men and <20 kg in women) and slowness were consistently more likely to have a fall, hip fracture, mobility limitation, or die than those without either slowness or muscle weakness.

CONCLUSION

Older men and women with both muscle weakness and slowness have a higher likelihood of adverse health outcomes. These results support the inclusion of grip strength and walking speed as components in a summary definition of sarcopenia. J Am Geriatr Soc 68:1429-1437, 2020.

Sarcopenia Definition: The Position Statements of the Sarcopenia Definition and Outcomes Consortium

OBJECTIVES

To develop an evidence-based definition of sarcopenia that can facilitate identification of older adults at risk for clinically relevant outcomes (eg, self-reported mobility limitation, falls, fractures, and mortality), the Sarcopenia Definition and Outcomes Consortium (SDOC) crafted a set of position statements informed by a literature review and SDOC's analyses of eight epidemiologic studies, six randomized clinical trials, four cohort studies of special populations, and two nationally representative population-based studies.

METHODS

Thirteen position statements related to the putative components of a sarcopenia definition, informed by the SDOC analyses and literature synthesis, were reviewed by an independent international expert panel (panel) iteratively and voted on by the panel during the Sarcopenia Position Statement Conference. Four position statements related to grip strength, three to lean mass derived from dual-energy x-ray absorptiometry (DXA), and four to gait speed; two were summary statements.

RESULTS

The SDOC analyses identified grip strength, either absolute or scaled to measures of body size, as an important discriminator of slowness. Both low grip strength and low usual gait speed independently predicted falls, self-reported mobility limitation, hip fractures, and mortality in community-dwelling older adults. Lean mass measured by DXA was not associated with incident adverse health-related outcomes in community-dwelling older adults with or without adjustment for body size.

CONCLUSION

The panel agreed that both weakness defined by low grip strength and slowness defined by low usual gait speed should be included in the definition of sarcopenia. These position statements offer a rational basis for an evidence-based definition of sarcopenia. The analyses that informed these position statements are summarized in this article and discussed in accompanying articles in this issue of the journal. J Am Geriatr Soc 68:1410-1418, 2020.

Application of Selected Muscle Strength and Body Mass Cut Points for the Diagnosis of Sarcopenia in Men and Women With or at Risk for HIV Infection

BACKGROUND

Persons with HIV may experience greater mobility limitations than uninfected populations. Accurate tools are needed to identify persons at greatest risk of decline. We evaluated the performance of novel muscle weakness metrics (grip, grip/body mass index [BMI], grip/weight, grip/total body fat, grip/arm lean mass) and association with slowness and falls in older persons with or at risk for HIV infection as part of the work of the Sarcopenia Definitions and Outcomes Consortium (SDOC).

METHODS

We assessed the prevalence of sarcopenia among 398 men (200 HIV+, 198 HIV-) from the Multicenter AIDS Cohort Study and 247 women (162 HIV+, 85 HIV-) from the Women's Interagency HIV Study using previously validated muscle weakness metrics discriminative of slowness. Sensitivity and specificity were used to compare new muscle weakness and slowness criteria to previously proposed sarcopenia definitions.

RESULTS

The prevalence of muscle weakness ranged from 16% to 66% among men and 0% to 47% among women. Grip/BMI was associated with slowness among men with HIV only. Grip/BMI had low sensitivity (25%-30%) with moderate to high specificity (68%-89%) for discriminating of slowness; all proposed metrics had poor performance in the discrimination of slowness (area under the curve [AUC] < 0.62) or fall status (AUC < 0.56). The combination of muscle weakness and slowness was not significantly associated with falls (p ≥ .36), with a low sensitivity in identifying those sustaining one or more falls (sensitivity ≤ 16%).

DISCUSSION

Clinical utility of new sarcopenia metrics for identification of slowness or falls in men and women with or at risk for HIV is limited, given their low sensitivity.