4. Characteristics of Screen Media use Associated With Higher Body Mass Index in Young Adolescents

Abstract

Purpose: TV viewing and video game play have been consistently associated with increased risk of overweight/obesity. Proposed mechanisms for this association include displacement of physical activity and/or sleep, and increased caloric intake in response to food/beverage advertising. To inform research on thesemechanisms, we investigated characteristics of TV viewing and video game play, amount of physical activity and sleep, and BMI using Measuring Youth Media Exposure (MYME), an innovative multimodal methodology, to collect comprehensive media exposure and health outcomes data on young adolescents. Methods: Adolescents 13to 15years old were recruited from a small New England city (N 126, mean age 14, 47% female, 57% Caucasian, 21% Hispanic). Participants’ heights and weights were measured and BMI calculated. Over one week, participants completed 24-hour time-use diaries (TUDs) on a randomly selected weekday and a Saturday, recording their activities throughout the day. Duration in minutes over the two days was calculated for TV viewing, video game play, computer use, sleep, and physical activity. During the sameweek, participants carried a handheld computer and responded to 4-6 signals a day by completing amomentary sampling (MS) questionnaire. The questionnaire asked participants to indicate their current activities andmedia use and towhich of these activities they were paying first, second, and third most attention. Number of incidents of primary and secondary/tertiary attention to TVandvideo games were calculated separately. We used linear regressionmodels that controlled for age, gender, time sleeping, and time engaged in physical activity, to estimate the association of TV viewing duration, primary attention to TV, and secondary/tertiary attention to TV with BMI. Similar models were run with video game play predicting BMI. Results: Eighty-seven participants (69%; 43 females) completed both TUDs and the MS week (M 29 reports). Participants spent an average of 6 hours 37 minutes watching TV and 1 hour 34 minutes playing video games over two TUD days. With MS, participants reported an average of 7 instances a week in which their primary attention was on TV and 3 where their secondary/tertiary attention was on TV. Participants’ primary attention was on video games an average of 2 times and their secondary/tertiary attention was on video games 0.33 times. Neither duration of TV viewing nor of video game play was significantly related to BMI. The number of moments that participants paid primary attention to TV was significantly positively related to BMI (p .04). For each additional report of primary attention to TV, participants’ BMI increased by .262 points (95% CI [.011, .506]). Neither TV viewing at secondary/tertiary level of attention nor video games at any level of attention was significantly associated with BMI. Conclusions: Attention to TV, but not total time watching TV or playing video games, was associated with higher BMI among young adolescents. These findings support the hypothesis that the link between screen media use and obesity is at least partially due to the influence of food/beverage advertising. Further research is necessary to fully understand the pathway linking attention to screen media and weight-related outcomes. Sources Of Support: NICHD 1R21HD054734. 5.