Risk phenotype for sarcopenia in older adults from Amazonas, Brazil; a cross-sectional study.

BACKGROUND: There are several markers for the suspicion, identification, and confirmation of sarcopenia. OBJECTIVES: To analyse the importance of several markers for assessing sarcopenia by classifying phenotypes based on five domains: symptomatology, muscle function, muscle mass, physical performance, and physical function. METHODS: A cross-sectional study analysing 312 older adults (72.6±7.8 yrs) was conducted in Novo Aripuanã, Amazonas, Brazil. Symptoms of sarcopenia were determined with the SARC-Calf; muscle function was assessed using the 30-Chair Stand test (CST), 30-CST power, and handgrip strength (HGS) with and without normalisation for body mass/height; the skeletal muscle mass index (SMMI) was estimated from anthropometry; physical performance was determined through the 4-m gait speed (GS) and 6-min walking test (6MWT); and physical function was determined with the Composite Physical Function Scale (CPF). RESULTS: Cluster analysis revealed two phenotypes (at risk vs not at risk for sarcopenia) and the contribution of each marker (ranged from 0 to 1). In men, the contribution of each marker was: 1 for SARC-Calf, 0.18 for SMMI, 0.09 for 30-CST power and 0.06 for HGS; in women: 1 for SARC-Calf, 0.25 for 30-CST power, 0.22 for SMMI, 0.06 for GS, 0.04 for HGS, and 0.03 for CPF. Considering the cutoff values proposed by Rikli and Jones (2013) for physical function and Cruz-Jentoft et al. (2019) for the other domains, the risk profile for sarcopenia was characterized by: high SARC-Calf in both sexes (men:51.8 vs 3.6%, p<0.001; women:71.2 vs 1.1%, p<0.001), low SMMI (men:73.2 vs 44.6%, p<0.002; women:44.1 vs 23.6%, p = 0.002); in women, low GS (38.7 vs 12.4%, p<0.001) and low CPF (29.7 vs 15.7%, p = 0.020), and no differences in HGS between groups in both sexes. CONCLUSIONS: SARC-Calf, SMMI, and 30-CST were more relevant markers for sarcopenia risk in older adults of both sexes, GS and CPF played also an important role in women.

Maternal Education and Academic Achievement in Schoolchildren: The Role of Cardiorespiratory Fitness.

OBJECTIVES: To examine the relationship between maternal education, cardiorespiratory fitness, and academic achievement in schoolchildren, specifically whether the association between maternal education and academic achievement is mediated by cardiorespiratory fitness. STUDY DESIGN: This is a secondary analysis of a cross-sectional study including 478 Spanish schoolchildren aged 8-11 years. ANOVA was used to test differences in cardiorespiratory fitness by maternal education level. ANCOVA was used to test the differences in academic achievement by the educational level of mothers and the cardiorespiratory fitness of children, controlling for each other. A mediation analysis was used to test if the relationship between maternal education and academic achievement was explained by cardiorespiratory fitness. RESULTS: A higher level of maternal education was associated with a higher cardiorespiratory fitness level and academic achievement in children; moreover, the cardiorespiratory fitness level in children was associated with better academic achievement (P < .05). Finally, cardiorespiratory fitness acted as a partial mediator of the relationship between maternal education and academic achievement in boys (z = 1.81; P = .03) but not in girls (z = 0.86; P = .19), explaining 6.54% of this relationship for the total sample and 6.67% for boys. CONCLUSIONS: This study suggests that the benefits of maternal education on academic achievement are partially explained by the mediating role of cardiorespiratory fitness.

Obesity as a Mediator between Cardiorespiratory Fitness and Blood Pressure in Preschoolers.

OBJECTIVES: To analyze the relationships between body mass index (BMI), cardiorespiratory fitness (CRF), and blood pressure (BP), and to examine whether obesity acts as a mediator between fitness and BP in children. STUDY DESIGN: A cross-sectional analysis using a population-based sample of 1604 school children aged 4-7 years attending 21 schools from the provinces of Ciudad Real and Cuenca, Spain, was undertaken. Data on anthropometric variables, BP measurements, and CRF were collected. The relationships between body composition (BMI, percent body fat, and waist circumference), CRF, and mean arterial pressure was estimated using Pearson correlation coefficients. ANCOVA tested the differences in BP measurements by categories of BMI and CRF, controlling for different sets of confounders. The PROCESS macro developed by Preacher and Hayes was used for mediation analysis. RESULTS: BP values were significantly higher in school children with excess weight and poorer CRF. In addition, BMI acts as a full mediator in the association between CRF and mean arterial pressure in boys at 62.28% (z = -5.433; P ≤ .001) and a partial mediator in girls at 35.24% (z = -5.246; P ≤ .001). CONCLUSIONS: BMI mediates the relationship between CRF and mean arterial pressure. These findings highlight the importance of maintaining a healthy weight for the prevention of high BP levels in childhood. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01971840.