Serum Creatinine-Cystatin C Based Screening of Sarcopenia in Community Dwelling Older Adults: A Cross-Sectional Analysis

OBJECTIVES

To compare the discriminative capabilities for the manifestation of sarcopenia or physical frailty between serum creatinine- and cystatin C-derived indices among community-dwelling older adults.

DESIGN

Cross-sectional study.

SETTING

Primary Care and Community.

PARTICIPANTS

We utilized a subset of data from the Frail Elderly in the Sasayama-Tamba Area (FESTA) study, which was initiated in 2015 to gather comprehensive information on various health-related parameters among community-dwelling older individuals (age ≥65 years).

MEASUREMENTS

Five serum creatinine-cystatin C based indices including the Sarcopenia Index, the serum creatinine/cystatin C ratio, the disparity between serum cystatin-C-based and creatinine-based estimated GFR, the total body muscle mass index (TBMM), and the prediction equation for skeletal muscle mass index (pSMI) were employed. Sarcopenia and physical frailty were identified based on the Asian Working Group for Sarcopenia criteria and the revised Japanese version of the Cardiovascular Health Study criteria, respectively. The receiver operating characteristic (ROC) and logistic regression analyses were performed to assess the discriminative abilities of these tools.

RESULTS

In the analysis of 954 participants, 52 (5.5%) were identified with sarcopenia and 35 (3.7%) with physical frailty. Regarding sarcopenia discrimination, TBMM and pSMI both exhibited area under the curve (AUC) values exceeding 0.8 for both men and women. Concerning the identification of physical frailty, AUC values ranged from 0.61 to 0.77 for males and 0.50 to 0.69 for females. In the multivariate logistic regression analyses, only TBMM and pSMI consistently displayed associations with sarcopenia, irrespective of sex (P<0.001, respectively). On the other hand, no consistent associations were observed between the indices and physical frailty.

CONCLUSIONS

This study provides a robust association of a serum creatinine- and cystatin C-derived indices, especially TBMM and pSMI, with sarcopenia among community-dwelling older adults. Conversely, the application of these indices for the screening of physical frailty has its constraints, necessitating further investigation.

Cross-Sectional and Longitudinal Associations of Creatinine-to-Cystatin C Ratio with Sarcopenia Parameters in Older Adults

OBJECTIVES

Accumulating evidence from cross-sectional studies suggests that the serum creatinine-to-cystatin C ratio (CCR) may be a useful biomarker for sarcopenia. This study aimed to assess the cross-sectional and longitudinal associations of CCR with sarcopenia and its parameters in community-dwelling older adults.

DESIGN

Cross-sectional and longitudinal study.

SETTING AND PARTICIPANTS

This 6-year prospective cohort study included the repeated measurement data from 1,253 Japanese residents (662 males and 591 females) aged ≥65 years who underwent medical checkups in Kusatsu and Hatoyama, Japan. A total of 4,421 observations were collected.

MEASUREMENTS

The CCR was grouped into quartiles by sex (Q1-Q4) using Q4 as the reference category. Sarcopenia was defined according to the Asian Working Group for Sarcopenia 2019 algorithm. Skeletal muscle mass index (SMI) measured using segmental multifrequency bioelectrical impedance analysis, handgrip strength (HGS), usual gait speed (UGS), and maximal gait speed (MGS) were measured repeatedly as sarcopenia parameters. The association of the CCR with changes in sarcopenia, SMI, HGS, UGS, and MGS during the 6-year period were analyzed using a generalized linear mixed-effects model.

RESULTS

The prevalence of sarcopenia at baseline was 13.1% (11.9% in males and 14.5% in females). In a cross-sectional analysis, the CCR quartile was inversely associated with sarcopenia and was positively associated with SMI, HGS, and MGS (P for trend < 0.001). In a longitudinal analysis during the 6 years, a significant increase in sarcopenia in Q2 (B = 1.1% point/year; P = 0.026 for group-by-time interaction) and significant declines in SMI (B = -0.01 kg/m2/year; P = 0.044 for group-by-time interaction) and MGS (B = -0.008 m/sec/year; P = 0.041 for group-by-time interaction) in Q1 were observed compared with Q4. However, the dose-response relationship was significant only for MGS (P = 0.033 for trend). No significant group-by-time interaction was observed for HGS. CCR was not significantly associated with UGS either cross-sectionally or longitudinally.

CONCLUSIONS

CCR is a useful biomarker regarding the status of sarcopenia. It may be used for sarcopenia screening even in older adults whose physical function is difficult to assess. However, further longitudinal studies are needed to determine whether CCR can be a predictor of future sarcopenia.

The Role of Sarcopenia in Overactive Bladder in Adults in the United States: Retrospective Analysis of NHANES 2011-2018

PURPOSE

To investigate the association between sarcopenia and overactive bladder (OAB) in a United States adult population from 2011 to 2018, and whether sarcopenia can predict the risk of OAB.

MATERIALS AND METHODS

We analyzed data from the 2011-2018 National Health and Nutrition Examination Survey in a cross-sectional study(NHANES) of 8746 participants, of whom 1213 were diagnosed with OAB, we analyzed correlations by sex, age, race, education level, marital status, household income-to-poverty ratio, hypertension, diabetes, strenuous work activity, moderate work activity, strenuous recreational activity, moderate recreational activity, blood urea nitrogen, creatinine, and uric acid levels using restricted cubic spline plots of dose-response curves, univariate and multivariate Logistic regression. Models based on sex, age, education, household income to poverty ratio, hypertension, diabetes, sarcopenia index, and cotinine were developed and evaluated using Nomogram, calibration curves, receiver operating characteristic curves, and clinical decision curves.

RESULTS

Of the 1213 OAB patients, 388 (32.0%) were male and 825 (68.0%) were female. Univariate and multivariate Logistic regression analysis showed that sarcopenia index was negatively correlated with the prevalence of OAB (OR=0.084, 95% CI, 0.056 - 0.130, P <0.001;OR=0.456, 95%CI, 0.215-0.968, P= 0.0041). Dose curve analysis of the sarcopenia index and prevalence of OAB showed that the prevalence of OAB decreased significantly with increasing sarcopenia index. Sarcopenia was positively correlated with OAB (OR=2.400, 95%CI, 2.000 - 2.800, P <0.001;OR=1.46, 95%CI, 1.096 -1.953, P = 0.010). In addition, our model shows that sarcopenia can predict the prevalence of OAB (AUC = 0.750) and has some clinical decision-making implications.

CONCLUSION

Sarcopenia is positively associated with the risk of OAB in United States adults and can be used as a predictor of OAB prevalence.

Transitional Dynamics of Sarcopenia and Associations of Nutritional Indices with State Transitions in Chinese aged ≥ 50

OBJECTIVES

Sarcopenia's temporal profile can be regarded as a dynamic process with distinct states, in which malnutrition plays an important role. This study aimed to address two research gaps: sarcopenia's transitional dynamics and associations of nutritional indices with state transitions in community-dwelling Chinese adults aged 50 and older.

DESIGN

A prospective population-based cohort study.

SETTING

Community-based setting in western China.

PARTICIPANTS

The analytic sample included data from 1910 participants aged ≥ 50 in the West China Health and Aging Trend study between 2018-2022.

MEASUREMENTS

We defined three states: the initial normal state (normal muscle strength, physical performance and muscle mass), the worst sarcopenia state (low muscle mass plus low muscle strength and/or low physical performance) and the intermediate subclinical state (the other scenarios). The relevant measurement methods and cut-off points were based on the 2019 AWGS consensus. Using a continuous-time multistate Markov model, we calculated probabilities of transitions between different states over 1, 2 and 4 years; we also examined associations between nutritional indices and transitions, including body mass index (BMI), calf circumference (CC), mid-arm circumference (MAC), triceps skinfold thickness (TST), albumin (ALB), geriatric nutrition risk index (GNRI), vitamin D (VitD) and prealbumin (PA).

RESULTS

For individuals in the normal state, their probabilities of remaining stable versus progressing to a subclinical state were 53.4% versus 42.1% at 2 years, and 40.6% versus 49.0% at 4 years. In the subclinical population, their 2- and 4-year chances were 60.2% and 51.2% for maintaining this state, 11.8% and 16.2% for developing sarcopenia, 28.0% and 32.6% for reverting to normal. For sarcopenic individuals, the likelihood of staying stable versus retrogressing to the subclinical state were 67.0% versus 26.3% at 2 years, and 48.3% versus 36.3% at 4 years. Increased BMI, CC, MAC, TST, ALB, GNRI and PA correlated with reversion from the subclinical state, among which increased TST, ALB and PA were also paralleled with reversion from sarcopenia, while decreased BMI, CC, MAC, TST and GNRI were associated with progression to sarcopenia. VitD was not significantly associated with any transitions.

CONCLUSION

This study reveals how sarcopenia changes over time in a Chinese population. It also highlights the usefulness of simple and cost-effective nutritional status indices for indicating state transitions, which can help identify individuals at risk of sarcopenia and guide targeted interventions within the optimal time window.

[Prevalence of Sarcopenia and Associated Factors in Community-dwelling Elderly Populations in Chengdu China]

OBJECTIVE

To determine the prevalence of sarcopenia in community-dwelling elderly populations in Chengdu and its associated risk factors.

METHODS

A total of 947 community dwelling residents aged ≥60 yr. in Chengdu participated in this study. Their appendicular skeletal muscle mass was measured through bioelectrical impedance analyses. Sarcopenia was defined using the diagnostic algorithm recommended by the Asia Working Group (AWGS) for Sarcopenia. Data in relation to the demographic characteristics, chronic diseases and life style of the participants were obtained through a questionnaire survey, which included the 15-item geriatric depression scale (GDS-15) and the mini nutritional assessment (MNA).

RESULTS

Overall, 10.5% of the elderly participants were identified with sarcopenia: 8.4% in men and 12.5% in women. The prevalence of sarcopenia increased with age: 2.3% in the 60-64 yr., 5.6% in the 65-74 yr., 19.7% in the ≥75 yr.. Age [odds ratio (OR)=1.109, 95% confldence interval (CI):1.054-1.168], smoking (OR=3.482, 95%CI:1.356-8.938) and Malnorishment (OR=5.598, 95%CI:2.677-11.709) are significant predictors of sarcopenia after adjustment for potential confounders.

CONCLUSION

Approximately 10% community-dwelling elderly in Chengdu have sarcopenis. Age, smoking, malnutrition are risk factors of sarcopenia.

Diagnosis of Sarcopenia in Long-Term Care Homes for the Elderly: the Sensitivity and Specificity of Two Simplified Algorithms with Respect to the EWGSOP Consensus

OBJECTIVE

To analyze the prevalence of sarcopenia in elderly care homes using the algorithm of the European Working Group on Sarcopenia in Older People (EWGSOP) and to evaluate the applicability, sensitivity, and specificity of two simplified algorithms that do not include gait speed measurement.

DESIGN

Cross-sectional study.

SETTING

Long-term care homes.

PARTICIPANTS

249 residents (187 females and 62 males) with a mean age of 84.9 ± 6.7 years (range, 70-106 yrs).

MEASUREMENTS

Cognitive impairment was evaluated with the Pfeiffer test, functional capacity with the Barthel index, walking ability by the Functional Ambulation Classification, muscle mass by bioelectrical impedance analysis, muscle strength by handgrip dynamometry and, gait speed over a distance of 4 m. Sarcopenia was assessed using the EWGSOP-recommended algorithm and two simplified algorithms (A and B). Algorithms A and B were validated with respect to the EWGSOP algorithm using the MacNemar test and obtaining the sensitivity and specificity, kappa coefficient, and area under the receiver operating characteristic curve (AUC).

RESULTS

Total or severe dependence was recorded in 67% of the 249 residents, severe or moderate cognitive impairment in 64%, inability to walk in 49%, and capacity to walk only with the aid of an ambulator or two people in 21%. The prevalence of sarcopenia was 63.0% by the EWGSOP algorithm, 62.9% by algorithm A and 63.2% by algorithm B (P = 1.000); 143 participants were diagnosed with sarcopenia by all three methods (P =1.000, K = 1.000).

CONCLUSION

Further studies that include residents with functional and/or cognitive impairment are required to validate these results, comparing the diagnostic performance of the EGWSOP algorithm with that of the simplified algorithms validated in the present report.

Performance of SARC-F in Regard to Sarcopenia Definitions, Muscle Mass and Functional Measures

OBJECTIVE

To assess the reliability and validity of Turkish version of SARC-F in regard to screening with current definitions of sarcopenia, muscle mass and functional measures.

DESIGN

Cross-sectional study.

PARTICIPANTS

Community-dwelling older adults aged >=65 years admitting to a geriatric outpatient clinic.

MEASUREMENTS

Muscle mass (bioimpedance analysis), handgrip strength, usual gait speed, chair sit-to-stand test, functional reach test, short physical performance battery, SARC-F questionnaire, FRAIL questionnaire Sarcopenia was evaluated with 4 current different definitions: European Working Group on Sarcopenia in Older People's (EWGSOP); Foundation for the National Institutes of Health (FNIH), International Working Group on Sarcopenia (IWGS) and Society on Sarcopenia, Cachexia and Wasting Disorders (SCWD).

RESULTS

After cross-cultural adaptation, 207 subjects were analysed in the clinical validation study. Mean age was 74.6±6.7 years, 67.6% were women. Against EWGSOP, FNIH, IWGS and SCWD definitions of sarcopenia, sensitivity of SARC-F were %25, 31.6%, 50% and 40%; specificity were 81.4%, 82.4%, 81.8% and 81.7%, respectively. Positive predictive values were between 5.1-15.4% and negative predictive values were 92.3-98.2%. Against parameters of low muscle mass, sensitivity were about 20% and specificity were about 81%. Against parameters of function; for low hand grip strength, sensitivity of SARC-F were 33.7% (for Turkish cut-off); 50% (for FNIH cut-off); specificity were 93.7% (for Turkish cut-off) and 85.8% (for FNIH cut-off). Against low UGS, poor performance in chair sit to stand test, functional reach test, SPPB and presence of positive frailty screening sensitivity were 58.3%, 39.2%, 59.1%, 55.2% and 52.1% while specificity were 97.3%, 97.8%, 88.1%, 99.3% and 91.2%, respectively.

CONCLUSION

The psychometric performance of Turkish SARC-F was similar to the original SARC-F. It revealed low sensitivity but high specificity with all sarcopenia definitions. Sensitivity and specificity were higher for muscle function tests reflecting its inquiry and input on functional measures. Our findings suggest that SARC-F is an excellent test to exclude muscle function impairment and sarcopenia. SARC-F is relatively a good screening test for functional measures.