Lajous Martín, Chavarro Jorge, Peterson Karen E, Hernández-Prado Bernardo, Cruz-Valdéz Aurelio, Hernández-Avila Mauricio, Lazcano-Ponce Eduardo
Center for Population Health Research, National Institute of Public Health, Av. Universidad 655, Col. Santa Maria Ahuacatitlán, CP 62508, Cuernavaca, Morelos, Mexico.
Public Health Nutr. 2009 Oct;12(10):1938-45. doi: 10.1017/S1368980009004881. Epub 2009 Feb 23.
To assess the association of time spent viewing television, videos and video games with measures of fat mass (BMI) and distribution (triceps and subscapular skinfold thicknesses (TSF, SSF)).
Cross-sectional validated survey, self-administered to students to assess screen time (television, videos and video games) and lifestyle variables. Trained personnel obtained anthropometry. The association of screen time with fat mass and distribution, stratified by sex, was modelled with multivariable linear regression analysis, adjusting for potential confounders and correlation of observations within schools.
State of Morelos, Mexico.
Males (n 3519) and females (n 5613) aged 11 to 18 years attending urban and rural schools in Morelos.
In males, screen time of >5 h/d compared with <2 h/d was significantly associated with a 0.13 (95% CI 0.04, 0.23) higher BMI Z-score, 0.73 mm (95% CI 0.24, 1.22) higher SSF and 1.08 mm (95% CI 0.36, 1.81) higher TSF. The positive association of screen time with SSF was strongest in males aged 11-12 years. Sexual maturity appeared to modify the association in females; a positive association between screen time and SSF was observed in those who had not undergone menarche (P for trend = 0.04) but not among sexually mature females (P for trend = 0.75).
Screen time is associated with fat mass and distribution among adolescent males in Mexico. Maturational tempo appears to affect the relationship of screen time with adiposity in boys and girls. Findings suggest that obesity preventive interventions in the Mexican context should explore strategies to reduce screen time among youths in early adolescence.
评估观看电视、视频及玩电子游戏的时长与脂肪量（体重指数）及分布（肱三头肌和肩胛下皮褶厚度）测量指标之间的关联。
采用经过验证的横断面调查，由学生自行填写以评估屏幕使用时间（电视、视频及电子游戏）和生活方式变量。训练有素的人员进行人体测量。通过多变量线性回归分析对屏幕使用时间与脂肪量及分布之间的关联进行建模，按性别分层，并对潜在混杂因素及学校内观察值的相关性进行校正。
墨西哥莫雷洛斯州。
墨西哥莫雷洛斯州城乡学校11至18岁的男性（n = 3519）和女性（n = 5613）。
在男性中，每天屏幕使用时间>5小时与<2小时相比，体重指数Z评分显著高出0.13（95%可信区间0.04, 0.23），肩胛下皮褶厚度高出0.73毫米（95%可信区间0.24, 1.22），肱三头肌皮褶厚度高出1.08毫米（95%可信区间0.36, 1.81）。屏幕使用时间与肩胛下皮褶厚度之间的正相关在11至12岁男性中最为明显。性成熟似乎改变了女性中的这种关联；在未初潮的女性中观察到屏幕使用时间与肩胛下皮褶厚度之间存在正相关（趋势P值 = 0.04），而在性成熟女性中未观察到这种相关性（趋势P值 = 0.75）。
在墨西哥，屏幕使用时间与青少年男性的脂肪量及分布有关。成熟节奏似乎影响男孩和女孩中屏幕使用时间与肥胖的关系。研究结果表明，墨西哥的肥胖预防干预措施应探索减少青春期早期青少年屏幕使用时间的策略。
