RESUMEN

Phase angle is a composite measure that combines two raw bioelectrical impedance analysis measures: resistance and reactance. Phase angle has been considered an indicator of cellular health, integrity, and hydration. As inflammation and oxidative stress can damage cellular structures, phase angle has potential utility in early detecting inflammatory and oxidative status. Herein, we aimed to critically review the current understanding on the determinants of phase angle and its relationship with markers of inflammation and oxidative stress. We also discussed the potential role of phase angle in detecting chronic inflammation and related adverse outcomes. Several factors have been identified as predictors of phase angle, including age, sex, extracellular to intracellular water ratio, and fat-free mass. In addition to these factors, body mass index (BMI) also seems to influence phase angle. Available data also show that lower phase angle values are correlated (negligible to high correlation coefficients) with higher c-reactive protein, tumour necrosis factor-α, interleukin-6, and interleukin-10 in studies involving the general and aging populations, as well as patients with chronic conditions. Although fewer studies have evaluated the relationship between phase angle and markers of oxidative stress, available data also suggest that phase angle has potential to be used as an indicator (for screening) of oxidative damage. Future studies including diverse populations and bioelectrical impedance devices are required to confirm the validity and accuracy of phase angle as a marker of inflammation and oxidative stress for clinical use.

Asunto(s)

RESUMEN

OBJECTIVE: To compare adiposity indexes in physical activity individuals to evaluate behavior, diagnostic ability and to determine which parameter best reflects and diagnoses body fatness. METHODS: A cross-sectional study was performed on 100 physically active individuals (59% female). The participants were submitted to anthropometric and body composition evaluation; we measured weight, height, circumferences, blood pressure and bioelectrical impedance analysis. A physical activity questionnaire (IPAQ, short version) was applied, as well as a questionnaire about the possible use of nutritional supplementation. The data were statistically analyzed, with significance level set at p <0.05. RESULTS: Mean age, height, weight and BMI were 24.2 ± 6.65 years, 169.5 ± 8.94 cm, 69.1 ± 14.83 kg and 23.9 ± 4.19 kg/m2, respectively, with a significant difference between the genders, except for age. Most of the subjects were in the normal weight range, with a BMI of 18.5 to 24.9 kg/m2, and were very active. BMIfat correlated better with body fat for males (r = 0.896) and females (r = 0.935), followed by BMI (0.689 and 0.767, respectively) and BAI (0.590 and 0.718). CONCLUSIONS: Adiposity indexes are viable alternatives for the diagnosis of obesity and should be more explored as fast, practical and low cost measures in clinical practice.

OBJETIVO: comparar os índices de adiposidade em indivíduos praticantes de atividade física para avaliar o comportamento, a capacidade diagnóstica e determinar qual parâmetro melhor reflete e diagnostica a adiposidade corporal. MÉTODOS: Um estudo transversal foi realizado em 100 indivíduos fisicamente ativos (59% mulheres). Os participantes foram submetidos à avaliação antropométrica e de composição corporal, sendo aferidos peso, estatura, circunferências, pressão arterial e análise de impedância bioelétrica. Foi aplicado um questionário de atividade física (IPAQ, versão curta), além de um questionário sobre o possível uso da suplementação nutricional. Os dados foram analisados ​​estatisticamente, com nível de significância estabelecido em p <0,05. RESULTADOS: as médias de idade, estatura, peso e IMC foram 24,2 ± 6,65 anos, 169,5 ± 8,94 cm, 69,1 ± 14,83 kg e 23,9 ± 4,19 kg/m2, respectivamente, com diferença significativa entre os gêneros, exceto para idade. A maioria dos sujeitos estava na faixa de peso normal, com um IMC de 18,5 a 24,9 kg/m2, e eram muito ativos. O BMIfat foi melhor correlacionado com a gordura corporal para homens (r = 0,896) e mulheres (r = 0,935), seguido pelo IMC (0,689 e 0,767, respectivamente) e BAI (0,590 e 0,718). CONCLUSÕES: Os índices de adiposidade são alternativas viáveis ​​para o diagnóstico da obesidade e devem ser mais explorados como medidas rápidas, práticas e de baixo custo na prática clínica.

Asunto(s)

RESUMEN

OBJECTIVE: To measure the accuracy of the body mass index (BMI), BMI adjusted for fat mass (BMIfat), body adiposity index (BAI), BAI for the Fels Longitudinal Study sample, Clínica Universidad de Navarra-Body Adiposity Estimator, and fat mass index and to compare the accuracy to that of bioelectrical impedance and dual-energy x-ray absorptiometry (DXA) in a sample of the Brazilian population. METHODS: A cross-sectional study conducted on 240 hospitalized patients, 43 (18%) male and 197 (83%) female. Mean patient ages were 53.0 ± 13.3 y for males and 53.49 ± 14.0 y for females. All subjects underwent anthropometric evaluation, bioelectrical impedance, and DXA, which permitted the calculation of the indices. The level of significance was set at P < 0.05 in the statistical analyses. RESULTS: Mean subject age (y), weight (kg), and height (cm) were 53.0 ± 13.3 and 53.4 ± 14.0; 72.8 ± 14.9 and 67.6 ± 14.0; and 171.0 ± 8.0 and 157.0 ± 7.0 for men and women, respectively. Excess weight was detected in 67.4% and 66% according to the BMI, in 30% and 69.5% according to the BMIfat, and in 51% and 38% according to the BAI for men and women, respectively. Pearson correlation revealed that BMIfat clearly showed a better correlation (r = 0.67) with DXA than the remaining tools. The Clínica Universidad de Navarra-Body Adiposity Estimator was the only body adiposity parameter that was significantly higher in men compared to women. CONCLUSION: The results suggest that BMIfat is the index best related to the prediction of body fat and that the BAI did not exceed the limits of the BMI. Further studies of this type are needed to strengthen the present findings.

Asunto(s)

RESUMEN

OBJECTIVE: To compare the diagnostic performance of adiposity indeces body mass index (BMI), body mass index adjusted for fat mass (BMIfat), body adiposity index (BAI) and body adiposity index for the Fels Longitudinal Study sample (BAIFels) and the overweight detection in a sample of the Brazilian population. METHODS: Cross-sectional study with 501 individuals (female/male = 387/114), which underwent anthropometric measurements and body composition for subsequent calculation of adiposity indices. Statistical analyzes considered p < 0.05 as statistically significant. RESULTS: The averages were: age of 46.94 ± 14.22 years and 48.05 ± 14.40 years, weight 79.5 ± 16, 14 kg and 70.42 ± 16,62 kg, height 172.86 ± 7.6 cm and 159.0 ± 7,35 cm, for men and women, respectively. According to the eutrophic ratings and overweight, the BMIfat ranked 40.3% and 34.0% for men and 21.7% and 65.0% for females, r espectively. While the BAI held 47.7% and 62.3% for men and 65.6% and 34.4% for women, respectively. The receiver operating characteristic (ROC) curve of BMIfat was clearly superior to all other indexes for both men (93.1%) and women (97.8%), respectively. CONCLUSION: Findings suggest that BMIfat is the index that has better relationship with the prediction of body fat, BAI did not exceed the limitations of BMI. Future studies should seek to expand this study by adopting the gold standard methods such as DXA and it is necessary to extend the investigation of the validity of adiposity indices to different ethnic groups.

Asunto(s)

RESUMEN

Metabolism disorders, as well as body shape abnormalities, have been associated with the introduction of antiretroviral therapy. The objective of this study was to compare the diagnostic ability of adiposity indices and to discuss criteria for the classification of lipodystrophy and sarcopenia (SP) in HIV-positive individuals. Anthropometric measurements were determined in 268 individuals of both genders, also submitted to the dual-energy X-ray absorptiometry exam. The adiposity indices calculated were body mass index, body mass index adjusted for fat mass (BMIfat), body adiposity index, body adiposity Index for the Fels Longitudinal Study sample, and The Clínica Universidad de Navarra body adiposity estimator. The presence of lipodystrophy was evaluated using the fat mass ratio (FMR). SP was classified using the appendicular lean mass/height2 ratio. The subjects were divided into 3 groups: HIV+LIPO+ (n = 41), HIV+LIPO- (n = 65), and control (C, HIV-negative individuals; n = 162). Among the adiposity indices assessed, BMIfat showed the strongest correlation with total body fat (in percent) for men (r = 0.87, p < 0.001) and women (r = 0.92, p < 0.001). The frequency of SP was 44.8% and 41.7% in HIV+LIPO+, 27.8% and 20.7% in HIV+LIPO- and 63.3% and 45.45% in C, for men and women, respectively. The cutoff point suggested for the diagnosis of lipodystrophy according to the FMR was 1.14. The adiposity indices, particularly the BMIfat, have strong correlation with body fat determined by dual-energy X-ray absorptiometry in HIV-positive patients. The implementation of FMR is recommended for more standardized estimates of the frequency of lipodystrophy.

Asunto(s)

RESUMEN

INTRODUCTION: Body mass index (BMI) has been one of the methods most frequently used for diagnose obesity, but it isn't consider body composition. OBJECTIVE: This study intends to apply one new adiposity index, the BMI adjusted for fat mass (BMIfat) developed by Mialich et al. (2011), in a adult Brazilian sample. METHODS: A cross-sectional study with 501 individuals of both genders (366 women, 135 men) aged 17 to 38 years and mean age was 20.4 ± 2.8 years, mean weight 63.0 ± 13.5 kg, mean height 166.9 ± 9.0 cm, and BMI 22.4 ± 3.4 kg/m2. RESULTS AND DISCUSSION: High and satisfactory R2 values were obtained, i.e., 91.1%, 91.9% and 88.8% for the sample as a whole and for men and women, respectively. Considering this BMIfat were developed new ranges, as follows: 1.35 to 1.65 (nutritional risk for malnutrition), > 1.65 and ≤2.0 (normal weight) and > 2.0 (obesity). The BMIfat had a more accurate capacity of detecting obese individuals (0.980. 0.993, 0.974) considering the sample as a whole and women and men, respectively, compared to the traditional BMI (0.932, 0.956, 0.95). Were also defined new cut-off points for the traditional BMI for the classification of obesity, i.e.: 25.24 kg/m2 and 28.38 kg/m2 for men and women, respectively. CONCLUSION: The BMIfat was applied for the present population and can be adopted in clinical practice. Further studies are needed to determine its application to different ethnic groups and to compare this index to others previously described in the scientific literature.

Introducción: El índice de masa corporal (IMC) es uno de los métodos que se utilizan con mayor frecuencia para diagnosticar la obesidad, pero ese no considera la composisión corporal. Objetivo: Este estudio objetivó aplicar un nuevo índice de adiposidad, el IMC ajustado por la masa de grasa (BMIfat) desarrollado por Mialich et al . (2011), en una población adulta brasileña. Métodos: Estudio transversal con 501 individuos de ambos sexos (366 mujeres y 135 hombres) entre 17 y 38 años, edad media de 20,4 ± 2,8 años, con una media de peso de 63,0 ± 13,5 kg, con una media de altura 166,9 ± 9,0 cm, y IMC 22,4 ± 3,4 kg/m2. Resultados y discusión: Se obtuvieron altos y satisfactorios valores de correlación (R2): 91,1% , 91,9% y 88,8% para la muestra en su conjunto y para los hombres y mujeres, respectivamente. Teniendo en cuenta este BMIfat se han desarrollado nuevas gamas, de la siguiente manera: 1,35-1,65 (riesgo nutricional para la malnutrición), > 1,65 y ≤2,0 (peso normal) y > 2,0 (obesidad). El BMIfat tiene una capacidad más precisa de detectar individuos obesos (0,980; 0,993; 0.974; considerando la muestra en su conjunto y las mujeres y los hombres, respectivamente), en comparación con el índice de masa corporal tradicional (0,932; 0,956; 0,95). También fueron definidos nuevos puntos de corte para el IMC tradicional para la clasificación de la obesidad: 25,24 kg/m2 y 28,38 kg/m2 para los hombres y mujeres, respectivamente. Conclusión: El BMIfat se aplicó para la población actual y puede ser adoptado en la práctica clínica. Se necesitan más estudios para determinar su aplicación a los diferentes grupos étnicos y para comparar ese índice con otros descritos previamente en la literatura científica.

Asunto(s)

RESUMEN

Introduction: Body mass index (BMI) has been one of the methods most frequently used for diagnose obesity, but it isn’t consider body composition. Objective: This study intends to apply one new adiposity index, the BMI adjusted for fat mass (BMIfat) developed by Mialich et al. (2011), in a adult Brazilian sample. Methods: A cross-sectional study with 501 individuals of both genders (366 women, 135 men) aged 17 to 38 years and mean age was 20.4 ± 2.8 years, mean weight 63.0 ± 13.5 kg, mean height 166.9 ± 9.0 cm, and BMI 22.4 ± 3.4 kg/m2 . Results and discussion: High and satisfactory R2 values were obtained, i.e., 91.1%, 91.9% and 88.8% for the sample as a whole and for men and women, respectively. Considering this BMIfat were developed new ranges, as follows: 1.35 to 1.65 (nutritional risk for malnutrition), > 1.65 and ≤ 2.0 (normal weight) and > 2.0 (obesity). The BMIfat had a more accurate capacity of detecting obese individuals (0.980. 0.993, 0.974) considering the sample as a whole and women and men, respectively, compared to the traditional BMI (0.932, 0.956, 0.95). Were also defined new cut-off points for the traditional BMI for the classification of obesity, i.e.: 25.24 kg/m2 and 28.38 kg/m2 for men and women, respectively. Conclusion: The BMIfat was applied for the present population and can be adopted in clinical practice. Further studies are needed to determine its application to different ethnic groups and to compare this index to others previously described in the scientific literature (AU)

Introducción: El índice de masa corporal (IMC) es uno de los métodos que se utilizan con mayor frecuencia para diagnosticar la obesidad, pero ese no considera la composisión corporal. Objetivo: Este estudio objetivó aplicar un nuevo índice de adiposidad, el IMC ajustado por la masa de grasa (BMIfat) desarrollado por Mialich et al. (2011), en una población adulta brasileña. Métodos: Estudio transversal con 501 individuos de ambos sexos (366 mujeres y 135 hombres) entre 17 y 38 años, edad media de 20,4 ± 2,8 años, con una media de peso de 63,0 ± 13,5 kg, con una media de altura 166,9 ± 9,0 cm, y IMC 22,4 ± 3,4 kg/m2 . Resultados y discusión: Se obtuvieron altos y satisfactorios valores de correlación (R2): 91,1%, 91,9% y 88,8% para la muestra en su conjunto y para los hombres y mujeres, respectivamente. Teniendo en cuenta este BMIfat se han desarrollado nuevas gamas, de la siguiente manera: 1,35-1,65 (riesgo nutricional para la malnutrición), > 1,65 y ≤ 2,0 (peso normal) y > 2,0 (obesidad). El BMIfat tiene una capacidad más precisa de detectar individuos obesos (0,980; 0,993; 0.974; considerando la muestra en su conjunto y las mujeres y los hombres, respectivamente), en comparación con el índice de masa corporal tradicional (0,932; 0,956; 0,95). También fueron definidos nuevos puntos de corte para el IMC tradicional para la clasificación de la obesidad: 25,24 kg/m2 y 28,38 kg/m2 para los hombres y mujeres, respectivamente. Conclusión: El BMIfat se aplicó para la población actual y puede ser adoptado en la práctica clínica. Se necesitan más estudios para determinar su aplicación a los diferentes grupos étnicos y para comparar ese índice con otros descritos previamente en la literatura científica (AU)

Asunto(s)