Fatores associados ao comportamento sedentário em adolescentes: uma análise do estudo de 'Avaliação de Comportamentos em Saúde e Estilo de Vida dos Adolescentes em Uberaba - ACtVU'

Abstract

Sedentary behavior (SB) has been considered an important modifiable risk factor for cardiovascular disease. With technological advancement, teenagers have spent considerable time in sedentary activities such as watching TV, playing video games and using the computer. Identifying associated factors, especially those that are modifiable, is paramount to proposing, designing and implementing successful interventions. Screen time (ST) has been used as a valid estimate to assess the time spent in SB among adolescents, however, little is known about the relationship of new portable media technologies (NPMT) and ST. Thus, this study aims a) to test the validity and reliability of the questionnaire Portable and Mobile Internet Technologies (Tecno-Q) in Brazilian adolescents; b) to determine the prevalence of ST and analyze its associated factors among adolescents; and c) to test the correlation between ST and the use of NPMT. Four steps were employed to validate the Techno-Q: development of the questionnaire; face validity and content; instrument clarity; reliability. For the second goal,1,009 school-age adolescents (14-19 years) volunteered to participate in the study. Participants answered two questionnaires: the COMPAC and Tecno-Q questionnaires. CS was classified from the ST (watching TV, playing video games and/or computer use) ≥ 2 h / day. Hierarchical binary logistic regression (OR) was employed for identifying factors associated with screen time. The Pearson correlation coefficient was used to test correlation between ST and use of NPMT. Tecno-Q scores for face validity, content validity, and clarity were 93%, 81%, and 95%. Kappa values ranged from 0.77 to 1.00; (p <0.01) for reliability of qualitative questions, while intraclass correlation coefficient values ranged from 0.94 to 0.98 for quantitative discrete questions. Bland-Altman measurement bias (continuous variables) of the Tecno-Q ranged from -1.93 to 61.12 minutes/day. In relation to the second aim of the study, SB prevalence was 81.6% (95% CI: 78.8 to 84.4), being higher among boys (84.9%; 95% CI: 82.6 to 87.2) than in girls (78.6%; 95% CI: 75.9 to 81.3, p = 0.018). OR for excessive ST were higher among boys (OR = 1.78; 95% CI: 1.23 to 2.56) compared to girls. Those in the 1st year and 2nd year also presented higher odds for excessive ST (OR = 1.89; 95% CI: 1.22 to 2.94 and OR = 1.97; 95% CI: 1.22 to 3.17) than those adolescents in the 3rd year. In addition, adolescents not doing an internship/work and those who with a lower fruit intake were less likely to present with excessive ST compared to those who had a job/internship (OR = 2.23; 95% CI: 1.54 to 3.23) and those who had a higher fruit intake (OR = 1, 43; 95% CI: 1.01 to 2.14). The correlations between ST and NTMP for boys ranged from r = 0.13 to 0.50; and for girls from r =.27 to .37. Tecno-Q showed satisfactory psychometric properties for validity, reliability and application. The prevalence of CS was high in both sexes. The adolescents identified with greater exposure to CS represent groups for interventions that aim at reducing sedentary entertainment based on screen time.