RESUMO
BACKGROUND: Physical activity (PA) declines in adolescence among black girls. This study assesses how moderate/vigorous physical activity (MVPA) relates to caregiver- vs. adolescent-reported parental support and whether the relationship is mediated by self-efficacy. METHODS: MVPA was assessed through accelerometry. Parental support and encouragement on adolescents' PA were reported by caregivers and adolescents with a 10-item Social Support and Exercise Survey. Adolescent-reported self-efficacy related to PA was assessed with an 8-item scale. Structural equation modeling assessed source variation (caregiver vs. adolescent report) in the relationship between parental support and MVPA and mediation through adolescent self-efficacy. RESULTS: The sample includes black adolescent girls (n = 272), with mean age of 11.6 years (standard deviation = 0.7), and average MVPA/day of 40.6 minutes. Caregiver/adolescent agreement on parental support was low (weighted Kappa <0.20). There was significant source variation in the parental support-MVPA relationship (Wald χ2 = 4.18, df = 1, p = 0.041); adolescent-reported support was related to MVPA (b = 0.40, standard error = 0.14, p = 0.003) and mediated through self-efficacy (95% bootstrapped confidence interval: 0.05-0.29). Caregiver-reported support or BMI z-score was not related to MVPA. CONCLUSIONS: The association between MVPA and adolescent-reported parental support among black adolescent girls is explained by positive self-efficacy. Findings suggest that effective adolescent/caregiver communication around parental support on PA relates to high adolescent self-efficacy and supports objectively measured PA. Additional research is merited to examine longitudinal patterns. Furthermore, although 51.5% of girls in the sample were overweight or obese, the lack of association between MVPA and body composition minimizes its implication for mitigating obesity among overweight/obese black adolescent girls.
Assuntos
Negro ou Afro-Americano , Exercício Físico/fisiologia , Pais , Autoeficácia , Apoio Social , Negro ou Afro-Americano/psicologia , Negro ou Afro-Americano/estatística & dados numéricos , Criança , Estudos Transversais , Feminino , Humanos , Obesidade Infantil , Inquéritos e QuestionáriosRESUMO
Despite the wide availability of antiretroviral drugs, more than 250,000 infants are vertically infected with HIV-1 annually, emphasizing the need for additional interventions to eliminate pediatric HIV-1 infections. Here, we aimed to define humoral immune correlates of risk of mother-to-child transmission (MTCT) of HIV-1, including responses associated with protection in the RV144 vaccine trial. Eighty-three untreated, HIV-1-transmitting mothers and 165 propensity score-matched nontransmitting mothers were selected from the Women and Infants Transmission Study (WITS) of US nonbreastfeeding, HIV-1-infected mothers. In a multivariable logistic regression model, the magnitude of the maternal IgG responses specific for the third variable loop (V3) of the HIV-1 envelope was predictive of a reduced risk of MTCT. Neutralizing Ab responses against easy-to-neutralize (tier 1) HIV-1 strains also predicted a reduced risk of peripartum transmission in secondary analyses. Moreover, recombinant maternal V3-specific IgG mAbs mediated neutralization of autologous HIV-1 isolates. Thus, common V3-specific Ab responses in maternal plasma predicted a reduced risk of MTCT and mediated autologous virus neutralization, suggesting that boosting these maternal Ab responses may further reduce HIV-1 MTCT.