Age-, sex-, and maturity-associated variation in the phase angle after adjusting for size in adolescents

Abstract

BackgroundApplied research using the phase angle (PhA) in children and adolescents has increased notably. Using multilevel modeling in a fully Bayesian framework, we examined the relationships between PhA, age, sex, biological maturity status, and body size in 10–16-year-old adolescents.MethodsThe sample comprised 519 adolescents (women, n = 241; men, n = 278) from Campinas, São Paulo, Brazil. Biological maturity status was assessed with self-examination of pubertal development for sexual maturity and maturity offset protocol to estimate age at peak height velocity (PHV) for somatic maturity status. Stature and body mass were measured by anthropometry. Phase angle was calculated based on raw resistance and reactance values (50 kHz frequency) obtained by bioelectrical impedance with the foot-to-hand technology.ResultsThe multilevel regression analysis revealed that boys had significantly higher values of phase angle than girls, adjusting for age group and sexual maturity status. Overall, older and more mature adolescents had higher values of phase angle. When considering aligning variation in the phase angle by distance to estimated PHV (maturity offset), there was a higher association between the phase angle and time before and after predicted age at PHV for boys (r = 0.31, 90% CI: 0.23 to 0.39) than girls (r = 0.2, 90% CI: 0.11 to 0.28). When including body mass in the multilevel models, corresponding changes in the overall body mass mediate most of the influence of the maturity status and age group on the phase angle.ConclusionThe present study demonstrated that the variability in phase angle is related to inter-individual variation in sex, age, and maturity status, as well as differences in body size. Research with adolescents considering phase angle should use multilevel modeling with standardized parameters as default to adjust for the concurrent influence of sex, age, maturity status, and body size.

Association between disability in activities of daily living and phase angle in hemodialysis patients

“…In our study, after adjusting for multiple variables, logistic regression analysis confirmed that low PhA remained strongly associated with disability in hemodialysis patients, further expanding our understanding of the clinical value of PhA. Consistent with previous studies [ 36 – 38 ], our findings demonstrated that male subjects had higher PhA values. The sex difference in PhA might be associated with higher proportion of muscle and water in males, whereas female tend to have a higher proportion of body fat in females.…”

Association between Phase Angle and Body Composition of Children and Adolescents Diagnosed with HIV Infection

“…The justifications discussed in the literature are mainly based on the presence of greater muscle mass in males compared to females [ 23 ]. However, it is important to extrapolate to other factors, such as changes in body water, especially during the maturation period, and body size (height) [ 13 ]. Therefore, it is believed that it is important to consider sex-stratified analyses, which can help understand the differences in physical growth, body composition, and lifestyle between sexes reported in the literature [ 23 ].…”

“…Moreover, adults with HIV have shown lower PhA values compared to those without infection [ 11 ]. The reasons for the lower PhA values in this population are not fully understood, but studies have indicated that a lower PhA is directly associated with increased subcutaneous adipose tissue, and depletion of both muscle mass and body mass [ 9 , 12 ]; Additionally, the literature has shown that factors such as age [ 13 ], sex, body dimensions, biological maturation [ 14 ], physical activity level [ 15 ], and hydration status can directly impact PhA values in different age groups [ 16 ] and in individuals with different health conditions [ 9 ]. Therefore, these factors should be considered in the interpretation of the results found.…”

The role of bioelectrical phase angle in patients with heart failure

“…The main determinants of PhA are age, sex, and body mass index (BMI) as men and younger individuals might demonstrate higher values in PhA [33][34][35]. Differences in the distribution of body fluids and variations in free-fat mass as well as weight explain the impact of the above-mentioned characteristics on the evaluation of PhA.…”