Estimating resting energy expenditure from dual-energy X-ray absorptiometry: A cross-sectional study in healthy young adults.

OBJECTIVE: To qualify a 3C approach model of dual-energy X-ray absorptiometry (DXA) to estimate multicomponent resting energy expenditure (REE) referenced by indirect calorimetry (IC). METHODS: A sample of 155 college students, of both sexes (18-30 years old) was evaluated. Anthropometric measures, REE by IC, and whole-body DXA-scans were performed. The REE for each body component was determined after transforming the components from the molecular (DXA) to the organ tissue level. Bland-Altman and proportional bias analyses were used to verify agreement between REE measured (REEIC ) and estimated (REEDXA ). RESULTS: Statistically significant differences were found for all sex comparisons (P < .001), except for age (P = .950). Differences from the final sex-specific models' were not found between REEIC and REEDXA (P > .05). Men also presented greater expenditure (P < .001) in each component, except for adipose tissue. The plots confirmed the validity of the model for both sexes, with low difference values between the measured and estimated REE. The mean of the differences of REEIC and REEDXA showed heteroscedasticity of the data for men (P = .004). The same error tendency was not evident for women (P = .333). CONCLUSIONS: This 3C model, estimating REE from a multicomponent approach, allows a new application of DXA as tool for understanding intraindividual differences in terms of the mass of metabolically active tissue. Sex and populational differences should be taken in account. Consequently, we present qualified sex-specific DXA models that can be applied in different contexts such as health and sports, besides considering interpersonal differences in terms of energy expenditure.

Sarcobesity: New paradigms for healthy aging related to taurine supplementation, gut microbiota and exercise.

Enigmatic sarcopenic obesity is still a challenge for science and adds to the global public health burden. The progressive accumulation of body fat combined with a dysfunctional skeletal muscle structure and composition, oxidative stress, mitochondrial dysfunction, and anabolic resistance, among other aggravating factors, together represent the seriousness and complexity of treating the metabolic disorder of sarcobesity in aging. For this reason, further studies are needed that encourage the support of therapeutic management. It is along these lines that we direct the reader to therapeutic approaches that demonstrate important, but still obscure, outcomes in the physiological conditions of sarcobesity, such as the role of taurine in modulating inflammatory and antioxidant mechanisms in muscle and adipose tissue, as well as the management of gut microbiota, able to systemically re-establish the structure and function of the gut-muscle axis, in addition to the merits of physical exercise as an instrument to improve muscular health and lifestyle quality.

Low handgrip strength is associated with falls after the age of 50: findings from the Brazilian longitudinal study of aging (ELSI-Brazil).

AIM: This study examined the association of low handgrip strength (HGS) for falls in middle-aged adults and older adults every half-decade of life. METHODS: This cross-sectional study was conducted using the public data from the first wave of the Brazilian Longitudinal Study of Aging (ELSI-Brazil). The participants were allocated into seven age groups 50-54, 55-59, 60-64, 65-69, 70-74, 75-79, and ≥ 80 years. Binary logistic regression analysis was performed to identify the odds ratio (OR) of low HGS to the falls regardless of confounding variables such as sex, balance, gait speed, and total number of health conditions. RESULTS: A total of 8,112 participants aged 50-105 years (median = 62.0 years): 3,490 males (median = 60.0 years) and 4,622 females (median = 63.0 years) attended the study. Altogether, 21.5% of participants experienced at least one fall. HGS gradually decreases over each half-decade of life. In addition, low HGS presented a significative OR (p < 0.05) for falls for age groups, until 80 s, even when considering confounding variables. CONCLUSIONS: Low HGS is associated with falls in middle-aged adults over their 50 s and remained a strong measure of falls across each subsequent half-decade of life, until 80 s.

Sleep quality and falls in middle-aged and older adults: ELSI-Brazil study.

OBJECTIVE: To verify the association between low self-reported sleep quality (LSQ) and fall in middle-aged and older adults every half-decade of life. METHOD: A cross-sectional study was conducted using data from the first wave (2015-2016) of the Brazilian Longitudinal Study of Aging (ELSI-Brazil), which is nationally representative. The sample consisted of 8,950 participants who were allocated into eight age groups: 50-54, 55-59, 60-64, 65-69, 70-74, 75-79, 80-84, and ≥ 85 years. The questionnaires used included self-reported sleep quality and the International Physical Activity Questionnaire short version. Fisher's exact test followed by binary logistic regression analysis was performed to identify the odds ratio of sleep quality for fall occurrence, controlled for confounding variables. RESULTS: Individuals aged 50-105 years (63.6 ± 10.2 years), 57.0% females and 43.0% males, participated in this study. Overall, 21.5% of participants experienced at least one fall. The relative frequency of participants classified as having high or LSQ remained constant across each half-decade of life. The LSQ exhibited a statistically significant OR (p < 0.05) for falls across age groups up to 84, even after accounting for confounding variables. CONCLUSION: LSQ is significantly associated with an increased occurrence of fall in adults aged >50 years, but not for ≥ 85 years regardless of sex and physical activity level.

Forecasting and validating fat mass ratio models through anthropometric measurements and health-related factors among people with HIV: a cross-sectional investigation.

Background: There is a limited research on predictive models of fat mass ratio (FMR) in people living with human immunodeficiency virus (HIV) (PWH). This study aimed to develop models considering anthropometric and health-related factors to predict and validate FMR in PWH regardless of sex. Methods: One hundred and six Brazilian PWH (46.4±9.8 years) were evaluated for body composition using dual-energy X-ray absorptiometry (DXA), body circumference (BC), and skinfold thicknesses (SKs). FMR predictive models were developed using stepwise linear regression, and their agreement with DXA was assessed using Bland-Altman plots. Cross-validation was performed using the predicted residual error sum of squares (PRESS) method. Results: Six FMR estimation models were developed for PWH, with adjusted R2 ranging from 0.43 to 0.72, standard error of the estimate (SEE) from 0.16% to 0.22%, and 95% confidence interval (CI) from 1.03 to 1.15. Model 6, including thigh SK, waist BC, therapy duration, subscapular SK, education years, and abdominal SK, exhibited the highest determination power (R2 adjusted 0.72, SEE 0.16%, and 95% CI: 1.06-1.15). The agreement between DXA-based FMR and predictive models showed minimal bias (-0.03 to +0.04) and narrower limits of agreement, particularly for the top-performing model (-0.33 to +0.30). Model 6 exhibited a high adjusted Q2PRESS (0.70) and low SPRESS (0.17). Conclusions: Our predictive models advance the study of body composition in PWH by consolidating the use of anthropometry for diagnosing and monitoring lipodystrophy regardless of sex.

Association of minimally processed and ultra-processed food daily consumption with obesity in overweight adults: a cross-sectional study.

Introduction: Introduction: food type represents higher odds of having obesity (OB), especially in overweight (OW) subjects. Minimally and ultra-processed foods can be associated with the odds of having OB in OW subjects. Objective: to investigate the association of minimally and ultra-processed food consumption with OB in OW adults. Methods: we included 15,024 participants (9,618 OW [25.0-29.9 kg/m2], 5,406 OB [≥ 30 kg/m2]) with ages ranging from 18 to 59 years from the 2019 baseline survey of the Surveillance of Risk Factors and Protection for Chronic Diseases by Telephone Survey (VIGITEL, Brazil). Minimally and ultra-processed food daily consumption scores and confounding variables (age, sex, scholarly, physical activity, hypertension, and diabetes) were measured. Binary logistic regression analyzes the association of minimally and ultra-processed food consumption scores with OB (odds ratio [OR]). Results: minimally processed food consumption score quartiles (1st = 1[food-score/day]; 2nd = 6[food-score/day]; 3rd = 7[food-score/day]; 4th = 8[food-score/day]) presented higher values compared to ultra-processed food (1st = 1[food-score/day]; 2nd = 1[food-score/day]; 3rd = 2[food-score/day]; 4th = 4[food-score/day]). For each score of minimally processed food consumed, there was a -5.9 % odds of OB. Thus, the higher quartile (4th) of minimally processed food consumption score represents less odds of OB (OR: -47.2 %; p < 0.001). Each ultra-processed food score consumed presented odds of 3.7 % of OB. Therefore, higher consumption of ultra-processed food (4th quartile) shows higher odds of OB (OR: +14.8 %; p < 0.001). All associations remained significatively even after being adjusted by the confounders. Conclusion: the consumption scores of minimally processed and ultra-processed foods presented a magnitude capable of impacting OW adults' odds of OB, even when controlled by sociodemographic factors, physical activity, hypertension, and diabetes.

Introducción: Introducción: el tipo de alimentación representa una mayor probabilidad de tener obesidad (OB), especialmente en sujetos con sobrepeso (SO). Los alimentos mínimamente procesados y ultraprocesados se pueden asociar con las probabilidades de tener OB en sujetos con SO. Objetivo: investigar la asociación del consumo de alimentos mínimamente procesados y ultraprocesados con la OB en adultos con SO. Métodos: se incluyeron 15.024 participantes (9.618 SO [25,0-29,9 kg/m2], 5.406 OB [≥ 30 kg/m2]) con edades entre 18 y 59 años de la encuesta basal 2019 de la Vigilancia de Factores de Riesgo y Protección para Enfermedades Crónicas mediante una Encuesta Telefónica (VIGITEL, Brasil). Se midió el puntaje de consumo diario de alimentos mínimamente procesados y ultraprocesados y variables de confusión (edad, sexo, escolaridad, actividad física, hipertensión y diabetes). Mediante una regresión logística binaria se analizóla asociación de las puntuaciones de consumo de alimentos mínimamente procesados y ultraprocesados con la OB (odds ratio [OR]). Resultados: los cuartiles de puntuación de consumo de alimentos mínimamente procesados (1.º = 1[alimento-puntuación/día]; 2.º = 6[alimento-puntuación/día]; 3.º = 7[alimento-puntuación/día]; 4.º = 8[alimento-puntuación/día]) presentaron valores superiores en comparación con los alimentos ultraprocesados (1.º = 1[alimento-puntuación/día]; 2.º = 1[alimento-puntuación/día]; 3.º = 2[alimento-puntuación/día]; 4.º = 4[alimento-puntuación/día]). Por cada punto de alimentos mínimamente procesados consumidos, hubo una probabilidad de OB del -5,9 %. Por lo tanto, el cuartil más alto (4.º) de puntuación de consumo de alimentos mínimamente procesados representa menos probabilidades de OB (OR: -47,2 %; p < 0,001). Cada puntaje de alimentos ultraprocesados consumidos presentó probabilidades de 3.7 % de OB. Por lo tanto, un mayor consumo de alimentos ultraprocesados (cuartil 4.º) muestra mayores probabilidades de OB (OR: +14,8 %; p < 0,001). Todas las asociaciones se mantuvieron significativamente incluso después de ajustarlas por los factores de confusión. Conclusión:las puntuaciones de consumo de alimentos mínimamente procesados y ultraprocesados impactaron en la probabilidad de desarrollar OB en adultos con SB, incluso cuando se controló por factores sociodemográficos, actividad física, hipertensión y diabetes.

Anthropometric equations to estimate appendicular muscle mass from dual-energy X-ray absorptiometry (DXA): A scoping review.

BACKGROUND: Appendicular skeletal muscle mass (ASM) obtained from dual-energy x-ray absorptiometry (DXA) is recommended to quantify sarcopenia, but has limited availability in disadvantaged-income countries, moreover in an epidemiological context. Predictive equations are easier and less costly to apply, but a review of all available models is still lacking in the scientific literature. The objective of this work is to map, with a scoping review, the different proposed anthropometric equations to predict ASM measured by DXA. METHODS: Six databases were searched without restriction on publication date, idiom, and study type. A total of 2,958 studies were found, of which 39 were included. Eligibility criteria involved ASM measured by DXA, and equations proposed to predict ASM. RESULTS: predictive equations (n = 122) were gathered for 18 countries. The development phase involves sample size, coefficient of determination (r2), and a standard error of estimative (SEE) varying between 15 and 15,239 persons, 0.39 and 0.98, 0.07 and 3.38 kg, respectively. The validation phase involves a sample size, accuracy, and a SEE between 15 and 3,003 persons, 0.61 and 0.98, 0.09 and 3.65 kg, respectively. CONCLUSIONS: The different proposed predictive anthropometric equations of ASM DXA were mapped, including validated pre-existing equations, offering an easy-to-use referential article for clinical and research applications. It is necessary to propose more equations for other continents (Africa and Antarctica) and specific health-related conditions (e.g., diseases), once the equations can only have sufficient validity and accuracy to predict ASM generally when applied to the same population.

Handgrip strength asymmetry cut points to identify slow gait speed in six low- and middle-income countries: A cross-sectional analysis with 12,669 older adults.

BACKGROUND: Handgrip strength (HGS) asymmetry is associated with slow gait speed. Both mark muscle dysfunction, potential risk of falls, and adverse health outcomes. This association was found in older adults from high-income countries, but not yet studied in low- and middle-income countries. Moreover, there is no HGS asymmetry referential to identify the disabling process. Thus, our study aims to verify the association of HGS asymmetry with slowness in older adults from six low- and middle-income countries and to propose cut points to slowness. METHODS: A cross-sectional study with data from 12,669 older adults (≥60 years) of the Study on Global Aging and Adult Health (SAGE) conducted in six low- and middle-income countries were analyzed. Based in the difference between upper body sides HGS (asymmetry), participants were categorized in groups as 0.0-10.0% (reference group), 10.1-20.1%, 20.1-30.0% or >30.0%. Slow gait speed was established as <0.59 (men) and <0.51 (women) m/s. Associations of HGS asymmetry with gait speed were ascertained with logistic regression. HGS asymmetry index "[(HGS asymmetry*HGS)/(BMI*Age)]*100" cut points to identify slowness were generated with the ROC curve and Youden index (α = 5%). RESULTS: Compared to HGS reference group, those with HGS asymmetry of 10.1-20%, 20.1-30.0% and >30.0% had a superior odds for slowness [1.18(CI:1.02,1.42); 1.17(CI: 0.97; 1.44); and 1.21(CI:1.03;1.43), respectively]. HGS asymmetry index cut points to identify slowness were ≤1.14 (women) and ≤1.77 (men). CONCLUSIONS: HGS asymmetry association with slowness is present in economically disadvantaged countries. We proposed a new index for impaired muscle function with acceptable sensibility and specificity.

Characteristics of resistance training-based protocols in older adults with sarcopenic obesity: a scoping review of training procedure recommendations.

Background: Sarcopenic obesity (SO) is a clinical and functional disease characterized by the coexistence of obesity and sarcopenia. Resistance training (RT) characteristics for older adults with sarcopenia or obesity are already well established in the scientific literature. Nonetheless, we still do not know how detailed the RT protocols are described for older adults with SO. Therefore, we aimed to analyze the characteristics of RT programs, including each of their variables, recommended for older adults with SO. Methods: This is a scoping review study that was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis for Scoping Reviews. The search was carried out until November 2022 in PubMed/MEDLINE, EMBASE, Cochrane Library, Web of Science, Scopus, LILACS, Google Scholar, and medRxiv databases. The studies included SO diagnosis and RT as an intervention strategy. The RT variables analyzed were as follows: exercise selection, the volume of sets, the intensity of load, repetition cadence, rest interval between sets, and weekly frequency. Results: A total of 1,693 studies were identified. After applying the exclusion criteria, 15 studies were included in the final analysis. The duration of the RT intervention ranged from 8 to 24 weeks. All studies included full-body routines, with single/multi-joint exercises. Regarding the volume of sets, some studies fixed it in three sets, whereas others varied between one and three sets. The load was reported by repetition range and the weight lifted, elastic-band color/resistance, percentage of one repetition maximum, or perceived exertion scale. Repetition cadence was fixed in some studies, while it was self-selected between concentric and eccentric phases in others. The interval between sets of rest varied from 30 to 180 s. All studies reported progression overload during the interventions. Not all studies reported how the exercise selection, repetition cadence, and rest interval were made. Conclusion: The characteristics of RT protocols and their variables prescribed in the literature for older adults with SO were mapped. The lack of detail on some training variables (i.e., exercise selection, repetition cadence, and rest interval) was identified. RT protocols are heterogeneous and described only partially among studies. The recommendations for RT prescription details in older adults with SO are provided for future studies. Systematic review registration: https://osf.io/wzk3d/.

Appendicular Skeletal Muscle Mass Prediction in People Living With HIV: A Cross-sectional Study.

ABSTRACT: People living with HIV (PWH) experience an accelerated aging process. There is no anthropometric predictive model for appendicular skeletal muscle mass (ASM) in PWH. This study develops anthropometric models to predict and validate ASM measured by dual energy x-ray absorptiometry (DXA) in PWH; DXA scans were obtained for 125 PWH (male = 74; age >18 years) on antiretroviral therapy. Fat mass ratio was used for lipodystrophy diagnosis. A multiple stepwise linear regression considered ASM DXA as the dependent variable and validated by PRESS method. A high power of determination and low standard estimate error were found for ASM DXA -predicted (adjusted r2 = 0.84 to 0.87, standard estimate error = 1.7-1.6 kg) and high PRESS validation coefficients (Q 2PRESS = 0.84-0.86, S PRESS = 1.7-1.6 kg). The variables included were lipodystrophy diagnosis, medial calf circumference, sex, and total body weight. We present novel, reliable, and validated anthropometric models to predict ASM DXA in PWH.

Being Physically Active Leads to Better Recovery Prognosis for People Diagnosed with COVID-19: A Cross-Sectional Study.

The regular practice of physical activity helps in the prevention and control of several non-communicable diseases. However, evidence on the role of physical activity in mitigating worsening clinical outcomes in people with COVID-19 is still unclear. The aim of this study was to verify whether different levels of physical activity provide protection for clinical outcomes caused by SARS-CoV-2 infection. A cross-sectional study was conducted with 509 adults (43.8 ± 15.71 years; 61.1% female) with a positive diagnosis of COVID-19 residing in Ribeirão Preto, São Paulo, Brazil. Participants were interviewed by telephone to determine the severity of the infection and the physical activity performed. Binary logistic regression was used to indicate the odds ratio (OR) of active people reporting less harmful clinical outcomes from COVID-19. Active people had a lower chance of hospitalization, fewer hospitalization days, less respiratory difficulty and needed less oxygen support. The results suggest that active people, compared to sedentary people, have a lower frequency of hospitalization, length of stay, breathing difficulty and need for oxygen support. These results corroborate the importance of public policies to promote the practice of physical activity, in order to mitigate the severity of the clinical outcomes of COVID-19.

Normalizing calf circumference to identify low skeletal muscle mass in older women: a cross-sectional study.

INTRODUCTION: Introduction: functional limitation is a result of sarcopenia and is associated with loss of skeletal muscle mass (SMM). Cost-effective methods are important for the identification of sarcopenia. Objective: to propose cutoff points for normalized calf circumference (CC) in order to identify low SMM in older women based on their functional limitation. Methods: in this descriptive, cross-sectional study the CC values of a young female sample (n = 78) were used to establish cutoff points (-2 SD) for low SMM in older women (n = 67). Functional limitation was identified by the six-minute walk test (≤ 400 m). CC was normalized by body mass, height, and BMI. The diagnostic accuracy of CC was calculated with a ROC curve, using functional limitation as standard. Results: cutoff points and area under the curve (AUC) were: CC (≤ 28.5; 0.62); CC·body mass-1 (≤ 0.40; 0.63); CC·height-2 (≤ 8.52; 0.55) and CC·BMI-1 (≤ 1.10; 0.73). Only CC·BMI-1 achieved a desirable accuracy (AUC > 0.7) to distinguish functional limitation. Conclusion: the accuracy attained supports the use of CC·BMI-1 to identify low SMM in older women. In the clinical context it is possible to predict the risk of sarcopenia when sophisticated methods for determining SMM are not available.

INTRODUCCIÓN: Introducción: la limitación funcional es consecuencia de la sarcopenia y se asocia con la pérdida de masa muscular esquelética (MME). Los métodos rentables son importantes para la identificación de la sarcopenia. Objetivo: proponer puntos de corte para la circunferencia de la pantorrilla (CP), normalizada para identificar un MME bajo en mujeres mayores en función de su limitación funcional. Métodos: en este estudio descriptivo de carácter transversal se utilizaron los valores de CP de una muestra de mujeres jóvenes (n = 78) para establecer los puntos de corte (-2 DS) de la MME baja en las mujeres mayores (n = 67). La limitación funcional se identificó mediante la prueba de la marcha de seis minutos (≤ 400 m). La CP se normalizó por la masa corporal, la altura y el IMC. La precisión diagnóstica de la CP se calculó con la curva ROC, utilizando como estándar la limitación funcional. Resultados: los puntos de corte y el área bajo la curva (AUC) fueron: CP (≤ 28,5; 0,62); CP·masa corporal-1 (≤ 0,40; 0,63); CP·altura-2 (≤ 8,52; 0,55) y CP·IMC-1 (≤ 1,10; 0,73). Solo el CP·IMC-1 logró la precisión deseable (AUC > 0,7) para distinguir la limitación funcional. Conclusión: la precisión alcanzada respalda el uso de CP·IMC-1 para identificar la MME baja en las mujeres mayores. En el contexto clínico es posible predecir el riesgo de sarcopenia cuando no se dispone de métodos sofisticados para determinar la MME.

Identification of muscle weakness in older adults from normalized upper and lower limbs strength: a cross-sectional study.

BACKGROUND: To propose cut-off points for older adults' weakness for upper and lower limbs muscle strength normalized by body size with the ratio standard/muscle quality and allometric scaling. METHODS: Ninety-four community-dwelling older adults (69.1% women) were assessed for 49 body-size variables (anthropometry, body composition and body indexes), handgrip strength (HGS), one maximum repetition measurement for knee extensors (1RM), isokinetic knee extension peak torque at 60°/s (PT), and six-minute walk test (6MWT). Ratio standard or muscle quality (muscle strength/body size) and allometric scaling (muscle strength/body sizeb; when b is the allometric exponent) were applied for body-size variables significantly correlated with HGS, 1RM and PT. Cut-off points were computed according to sex based on mobility limitation (6MWT < 400 m) with ROC curve and Youden index. RESULTS: Absolute HGS, 1RM and PT cut-off points were not adequate because they were associated with body size (r > 0.30). But it was corrected with muscle strength normalization according to body size-variables: HGS (n = 1); 1RM (n = 24) and PT (n = 24). The best cut-off points, with the highest area under the curve (AUC), were found after normalization for men: HGS/forearm circumference (1.33 kg/cm, AUC = 0.74), 1RM/triceps skinfold (4.22 kg/mm, AUC = 0.81), and PT/body mass*height0.43 (13.0 Nm/kg*m0.43, AUC = 0.94); and for women: HGS/forearm circumference (1.04 kg/cm, AUC = 0.70), 1RM/body mass (0.54 kg/kg, AUC = 0.76); and PT/body mass0.72 (3.14 Nm/kg0.72; AUC = 0.82). CONCLUSIONS: Upper and lower limbs muscle weakness cut-off points standardized according to body size were proposed for older adults of both sexes. Normalization removes the effect of extreme body size on muscle strength (both sexes) and improves the accuracy to identify weakness at population level (for women, but not in men), reducing the risk of false-negative/positive cases.

Population specificity affects prediction of appendicular lean tissues for diagnosed sarcopenia: a cross-sectional study.

INTRODUCTION: Introduction: the estimation of appendicular lean soft tissue by DXA (ALSTDXA) is one of the criteria for the diagnosis of sarcopenia. However, this method is expensive and not readily avaiable in clinical practice. Anthropometric equations are low-cost and able to accurate predict ALST, but such equations have not been validated for male Brazilian older adults between the ages of 60 to 79 years. To this end, this study sought to validate the existing predictive anthropometric equations for ALST, and to verify its accuracy for the diagnosis of sarcopenia in male Brazilian older adults. Methods: this cross-sectional study recruited and enrolled 25 male older adults (69.3 ± 5.60 years). ALSTDXA and anthropometric measures were determined. ALST estimations with 13 equations were compared to ALSTDXA. The validity of the equations was established when: p > 0.05 (paired t-test); standard error of the estimate (SEE) < 3.5 kg; and coefficient of determination r² > 0.70. Results: two Indian equations met the criteria (Kulkarini 1: 22.19 ± 3.41 kg; p = 0.134; r² = 0.78; EPE = 1.3 kg. Kulkarini 3: 22.14 ± 3.52 kg; p = 0.135; r² = 0.82; SEE = 1.2 kg). However, these equations presented an average bias (Bland-Altman: 0.54 and 0.48 kg) and 'false negative' classification for the ALST index. Thus, three explanatory equations were developed. The most accurate equation demonstrated a high level of agreement (r2adj = 0.87) and validity (r²PRESS = 0.83), a low predictive error (SEEPRESS = 1.53 kg), and an adequate ALST classification. Conclusion: anthropometric models for predicting ALST are valid alternatives for the diagnosis and monitoring of sarcopenia in older adults; however, population specificity affects predictive validity, with risks of false positive/negative misclassification.

INTRODUCCIÓN: Introducción: uno de los criterios utilizados para el diagnóstico de la sarcopenia es la determinación de tejido blando magro apendicular por DXA (TBMADXA), método costoso que no siempre está disponible en la práctica clínica. Las ecuaciones antropométricas suponen un bajo coste y predicen bien el TBMA, pero con una validez desconocida para los varones brasileños de 60 a 79 años. Por lo tanto, nuestro objetivo fue validar las ecuaciones antropométricas existentes predictivas del TBMA y verificar su precisión para el diagnóstico de sarcopenia en varones brasileños de edad avanzada. Métodos: participaron en este estudio transversal 25 hombres de edad avanzada (69,3 ± 5,60 años). Se determinaron el TBMADXA y las medidas antropométricas. Las ecuaciones predictivas del TBMA se compararon con el TBMADXA. La validez de las ecuaciones en las comparaciones se confirmó cuando: p > 0,05 (prueba de la "t" pareada); error estándar estimado (EEE) < 3,5 kg; coeficiente de determinación r² > 0,70. Resultados: dos ecuaciones indias cumplieron los criterios (Kulkarini 1: 22,19 ± 3,41 kg; p = 0,134; r² = 0,78; EEE = 1,3 kg. Kulkarini 3: 22,14 ± 3,52 kg; p = 0,135; r² = 0,82; EEE = 1,2 kg). Sin embargo, presentaron sesgo promedio (Bland-Altman: 0,54 y 0,48 kg) y clasificación de 'falso negativo' para el índice de TBMA. Por lo tanto, se crearon tres ecuaciones explicativas. La ecuación más precisa mostró un alto acuerdo (r2adj = 0,87), uma alta validez (r²PRESS = 0,83), um bajo error predictivo (EEEPRESS = 1,53 kg) y uma clasificación del TBMA adecuada. Conclusión: los modelos antropométricos para predecir el TBMA son alternativas válidas para el diagnóstico y el seguimiento de la sarcopenia en los ancianos. Pero la especificidad de la población afecta a su validez predictiva, con riesgos de incorrección por clasificación falsa positiva/negativa.

One-repetition submaximal protocol to measure knee extensor muscle strength among older adults with and without sarcopenia: a validation study.

BACKGROUND: Dynamic knee extensor muscle strength is a valid measure among healthy older adults but has not been tested in the sarcopenia condition. This study's objective was to test the validity of a one-repetition submaximal strength protocol to measure dynamic knee extension strength in older adults with and without sarcopenia. METHODS: Ninety-four physically independent older adults (female: n = 64, 60 to 85 years; male: n = 29, 60 to 85 years) participated in this study in Brazil during 2016-2017. Sarcopenia was classified and isokinetic unilateral knee extension strength was measured at 60°/s. Bilateral dynamic knee extension strength was estimated with an extensor chair using one-repetition submaximal protocol. Validity was determined using Spearman's correlation with isokinetic muscle strength. RESULTS: The frequency of sarcopenia was 11.7%. Sarcopenic individuals presented lower body mass, body mass index and skeletal muscle index. Only chronological age was higher among the sarcopenic individuals. A high correlation was found between isokinetic unilateral knee extension strength and bilateral estimated one-repetition with submaximal protocol (r = 0.74; p <  0.001), when the presence (r = 0.71; p = 0.014) and absence of sarcopenia (r = 0.74; p <  0.001) were considered. The validity of the one-repetition submaximal protocol for bilateral knee extension was confirmed. CONCLUSIONS: The estimated measure of bilateral knee extension muscle strength can be used to monitor adaptations promoted by physical exercise for older adults with and without sarcopenia. The validation enable studies that will propose cutoff points to identify sarcopenia with this submaximal protocol. This will enable early diagnosis and better management of sarcopenia, a disease with adverse impacts for older adults.

Correction to: One-repetition submaximal protocol to measure knee extensor muscle strength among older adults with and without sarcopenia: a validation study.

[This corrects the article DOI: 10.1186/s13102-020-00178-9.].

Cut-off points of knee extension strength allometrically adjusted to identify sarcopenia risk in older adults: A cross-sectional study.

PURPOSE: Handgrip strength used to identify sarcopenia is not representative of overall strength, especially as greater muscle volume and consequent autonomy-mobility are concentrated in the lower limbs. While absolute strength or relative to body mass is used to define sarcopenia, this relationship is not always linear. The aim of this study was to establish allometrically adjusted cut-off points of lower limb (quadriceps) muscle strength to identify sarcopenia risk in older adults. METHODS: ninety-four physically independent individuals over the age of 60 were measured by DXA and sarcopenia was identified. The one-repetition maximum (1RM) test of knee extension strength was estimated using the extensor chair by the submaximal repetition protocol. The six-minute walk test performance was recorded. 1RM values were scaled by body mass (1RM/body mass) and allometrically adjusted (1RM/body massb). Cut-off points for sarcopenia from 1RM were defined with ROC curve and Youden index with functional limitation (walking distance<400 m). Analyzes considered sex (α = 5%). RESULTS: Sarcopenia was present in 10.6 % of participants. The exponents b obtained were 0.70 for women and 0.96 for men. Except for absolute 1RM in women, all areas under the curve were acceptable (>0.70). The cut-off points for women and men were respectively, 38.1 and 56.1 kg for 1RM, 0.53 and 0.85 for 1RM/body mass, 1.48 and 1.00 for 1RM/body massb. CONCLUSIONS: 1RM of knee extension scaled by body mass or allometrically adjusted is an effective parameter to identify sarcopenia in older adults. The proposed cut-off points could be used to monitor sarcopenia risk in geriatrics.

Cut-off points of appendicular lean soft tissue for identifying sarcopenia in older adults in Brazil: a cross-sectional study.

INTRODUCTION: Introduction: appropriate appendicular lean soft tissue (ALST) parameters to identify sarcopenia in Brazil are scarce. The use of international references may lead to a false positive diagnosis. The objective was to propose cut-off points to identify sarcopenia in older men and women using DXA-derived ALST values from a young adult population. Methods: this was an observational study with a cross-sectional analysis. University students of both sexes (n = 125), aged 20 to 30 years, underwent anthropometric measurements and DXA scanning to obtain their ALST (kg). Cut-off points for sarcopenia were set at -2 standard deviations (-2SDs) away from the mean ALST of a young sample. Absolute values and indices (ALST/height2, ALST/weight, and ALST/body mass index [BMI]) were considered as recommended by international consensus. Results: compared to women, men presented higher values of weight, height, BMI, bone mineral content, lean soft tissue, ALST, and ALST index (kg/m²). Only fat mass was higher in women, and age was not different between genders. The -2SD ALST indices obtained were ≤ 6.56 kg/m² for men and ≤ 4.67 kg/m² for women. They were below international and national values, which tended to classify false positives. Conclusions: the -2SD ALST values proposed here are validated cut-offs for identifying low muscle in older adults and to prevent misdiagnosis with sarcopenia. In addition, they contribute to efficient monitoring and control of this disease in geriatric populations.

INTRODUCCIÓN: Introducción: los parámetros apropiados de masa muscular esquelética apendicular (MMEA) para identificar la sarcopenia en Brasil resultan escasos. Ello se debe al uso de referencias internacionales, lo cual puede conducir a un diagnóstico falso positivo. El objetivo del presente trabajo es proponer puntos de corte para determinar la sarcopenia en hombres y mujeres mayores empleando valores de MMEA derivados de las DXA de una población de adultos jóvenes. Métodos: estudio observacional con análisis transversal. Estudiantes universitarios de ambos sexos (n = 125), de 20 a 30 años de edad, se sometieron a mediciones antropométricas y DXA para obtener el MMEA (kg). Los puntos de corte de la sarcopenia se establecieron en -2 desviaciones estándar (-2SD) de la media de MMEA de una muestra joven. Se consideraron los valores absolutos e índices (MMEA/altura2, MMAE/peso y MMAE/índice de masa corporal [IMC]), según lo recomendado por el consenso internacional. Resultados: los hombres, en comparación con las mujeres, presentaron valores superiores de peso, altura, IMC, contenido mineral óseo, masa magra, MMEA e índice MMEA (kg/m²). Por otro lado, solo la masa grasa fue mayor en las mujeres, no habiendo diferencias de edad entre ambos géneros. El índice MMAE -2SD obtenido fue ≤ 6,56 kg/m² para los hombres y ≤ 4,67 kg/m² para las mujeres. Dichos resultados, al encontrarse por debajo de los valores internacionales y nacionales, tienden a clasificar los falsos positivos. Conclusiones: los MMAE -2SD propuestos aquí son valores de corte validados para identificar las cuantificaciones musculares bajas en los adultos mayores y para prevenir el diagnóstico erróneo de sarcopenia. Además, contribuyen a la monitorización y el control eficiente de esta enfermedad en las poblaciones geriátricas.

Anthropometric cutoff points to identify lipodystrophy characteristics in people living with HIV/AIDS: an observational study.

INTRODUCTION: Introduction: currently, there is no consensus regarding accurate and low-cost methods for diagnosing lipodystrophy in people living with HIV/AIDS (PLWHA). The aim of this study was to propose anthropometric cutoff points for the diagnosis of lipodystrophy among PLWHA. Methods: we included 106 PLWHA (men = 65, women = 41) who are under antiretroviral therapy and have been clinically classified into either a "lipodystrophy" or "non-lipodystrophy" group. Anthropometric measurements included 19 regions of body perimeters and 6 skinfold thickness measures. The Youden index was used to establish anthropometric cutoff points for the diagnosis of lipodystrophy, using the mean values of the anthropometric data (referred to as "original") along with the "Z index" (ZI) values, which were adjusted by the "Phantom Strategy." The cutoff points were proposed when "original" anthropometric measurements and ZI values had a statistical significance of p < 0.01 and an area under the curve (AUC) higher than 70%. The size effect was assessed to verify the influence of lipodystrophy on each anthropometric measure. Results: our data analysis proposes sex-specific cutoff points for the diagnosis of lipodystrophy in PLWHA - 17 points using the "original" anthropometric measurements, and 20 using the ZI values (average effect size between 1.0 and 1.1, and AUC = 76.7% and 78%). Conclusions: our study proposes accurate cutoff points for the diagnosis of lipodystrophy using "original" anthropometric measurements and ZI values adjusted by the "Phantom Strategy." Our findings support the use of anthropometric measurements as a simplified method for diagnosing lipodystrophy and monitoring body composition alterations in people living with HIV/AIDS.

INTRODUCCIÓN: Introducción: no existe consenso con respecto a métodos precisos y de bajo coste para diagnosticar la lipodistrofia en personas que viven con VIH/SIDA (PVVS). El objetivo de este estudio es proponer puntos de corte antropométricos para el diagnóstico de lipodistrofia entre las PVVS. Métodos: se incluyeron 106 PVVS (hombres = 65, mujeres = 41) en tratamiento antirretroviral que se clasificaron clínicamente en dos grupos de "lipodistrofia" o "no lipodistrofia". Las mediciones antropométricas incluyeron 19 regiones de parámetros corporales y 6 medidas de pliegues cutáneos. El índice de Youden se utilizó para establecer puntos de corte antropométricos para el diagnóstico de lipodistrofia utilizando la media de los datos antropométricos (denominados "originales") junto con los valores del "índice Z" (IZ), que fueron ajustados por la "estrategia Phantom". Los puntos de corte se propusieron cuando las mediciones antropométricas "originales" y los valores de IZ fueron estadísticamente significativos con un valor p < 0,01 y un área bajo la curva (AUC) superior al 70%. Se evaluó el tamaño del efecto para verificar la influencia de la lipodistrofia en cada medida antropométrica. Resultados: se propusieron puntos de corte específicos según el sexo para el diagnóstico de lipodistrofia en PVVS: 17 puntos usando las medidas antropométricas "originales" y 20 usando los valores de IZ (tamaño del efecto promedio entre 1.0 y 1.1, y AUC = 76.7% y 78%). Conclusiones: se propusieron puntos de corte antropométricos para el diagnóstico de lipodistrofia. Las mediciones antropométricas son un método simplificado para diagnosticar y monitorear los cambios de composición corporal en las PVVS.

Sleep quality and falls in middle-aged and older adults: ELSI-Brazil study / Qualidade do sono e quedas em adultos de meia-idade e idosos: Estudo ELSI-Brasil / Calidad del sueño y caídas en adultos de mediana edad y mayores: Estudio ELSI-Brasil

ABSTRACT Objective: To verify the association between low self-reported sleep quality (LSQ) and fall in middle-aged and older adults every half-decade of life. Method: A cross-sectional study was conducted using data from the first wave (2015-2016) of the Brazilian Longitudinal Study of Aging (ELSI-Brazil), which is nationally representative. The sample consisted of 8,950 participants who were allocated into eight age groups: 50-54, 55-59, 60-64, 65-69, 70-74, 75-79, 80-84, and ≥ 85 years. The questionnaires used included self-reported sleep quality and the International Physical Activity Questionnaire short version. Fisher's exact test followed by binary logistic regression analysis was performed to identify the odds ratio of sleep quality for fall occurrence, controlled for confounding variables. Results: Individuals aged 50-105 years (63.6 ± 10.2 years), 57.0% females and 43.0% males, participated in this study. Overall, 21.5% of participants experienced at least one fall. The relative frequency of participants classified as having high or LSQ remained constant across each half-decade of life. The LSQ exhibited a statistically significant OR (p < 0.05) for falls across age groups up to 84, even after accounting for confounding variables. Conclusion: LSQ is significantly associated with an increased occurrence of fall in adults aged >50 years, but not for ≥ 85 years regardless of sex and physical activity level.

RESUMO Objetivo: Verificar a associação entre baixa qualidade do sono autorrelatada (BQS) e quedas em adultos de meia-idade e idosos a cada meia década de vida. Método: Um estudo transversal foi conduzido utilizando dados da primeira onda (2015-2016) do Estudo Longitudinal Brasileiro do Envelhecimento (ELSI-Brasil), que é nacionalmente representativo. A população consistiu em 8.950 participantes que foram alocados em oito grupos etários: 50-54, 55-59, 60-64, 65-69, 70-74, 75-79, 80-84 e ≥ 85 anos. Os questionários utilizados incluíram qualidade do sono autorrelatada e o Questionário Internacional de Atividade Física versão curta. O teste exato de Fisher seguido pela análise de regressão logística binária foi conduzida para identificar a razão de chances da BQS para ocorrência de queda, controlando por variáveis de confusão. Resultados: Pessoas com idades entre 50 e 105 anos (63,6 ± 10,2 anos), sendo 57,0% do sexo feminino e 43,0% do sexo masculino, participaram deste estudo. No geral, 21,5% dos participantes experimentaram pelo menos uma queda. A frequência relativa de participantes classificados como tendo BQS ou alta permaneceu constante em cada meia década de vida. A BQS exibiu uma OR (p < 0,05) notável para quedas em grupos etários até 84 anos, mesmo após o ajuste para variáveis de confusão. Conclusão: A BQS está significativamente associada a uma maior ocorrência de queda em adultos com mais de 50 anos, mas não para ≥ 85 anos, independentemente do sexo e do nível de atividade física.

RESUMEN Objetivo: Verificar la asociación entre la baja calidad del sueño autorreportada (BCS) y las caídas en adultos de mediana edad y mayores cada media década de vida. Método: Se realizó un estudio transversal utilizando datos de la primera oleada (2015-2016) del Estudio Longitudinal Brasileño sobre el Envejecimiento (ELSI-Brasil), que es representativo a nivel nacional. La muestra consistió en 8,950 participantes que fueron asignados a ocho grupos de edad: 50-54, 55-59, 60-64, 65-69, 70-74, 75-79, 80-84 y ≥ 85 años. Los cuestionarios utilizados incluyeron calidad del sueño autorreportada y el Cuestionario Internacional de Actividad Física versión corta. Se realizó una prueba exacta de Fisher seguida por un análisis de regresión logística binaria para identificar la razón de probabilidades de la calidad del sueño para la ocurrencia de caídas, controlando las variables de confusión. Resultados: Participaron en este estudio individuos con edades entre 50 y 105 años (63,6 ± 10,2 años), siendo el 57,0% mujeres y el 43,0% hombres. En general, el 21,5% de los participantes experimentaron al menos una caída. La frecuencia relativa de participantes clasificados como con alta calidad de sueño o baja calidad de sueño (BCS) se mantuvo constante a lo largo de cada media década de vida. La BCS mostró un OR (p < 0,05) notable para las caídas en grupos de edad hasta los 84 años, incluso después de ajustar por variables de confusión. Conclusión: La BCS está significativamente asociada con una mayor ocurrencia de caídas en adultos mayores de 50 años, pero no para ≥ 85 años, independientemente del sexo y del nivel de actividad física.