Association of communication methods and frequency with BMI among adolescents during the COVID-19 pandemic: findings from A-CHILD study.

Little is known about the differential impact of communication methods and BMI. Hence, this study aims to examine the association of in-person and online communication with BMI among 13-14-year-old students during the COVID-19 pandemic. This is a cross-sectional study which used data from the Adachi Child Health Impact of Living Difficulty study among Junior High School students in Adachi City, Tokyo in 2022(N = 3,178). A questionnaire was used to assess communication methods and frequency. BMI was categorized into overweight and obesity (≥ + 1SD), normal weight (-1SD to <+1SD) and underweight (<-1SD) based on WHO standard. Multinomial logistic regression was used to examine the association between communication methods and BMI. Reduced in-person communication frequency was associated with 94% higher risk of overweight and obese (RRR = 1.94, 95%CI; 1.38, 2.72) while increased online communication frequency was associated with 46% increased risk (RRR = 1.46, 95%CI; 1.10, 1.95). When online and in-person communications were adjusted simultaneously, only reduced in-person communication frequency was associated with a high risk of overweight and obese (RRR = 1.56, 95%CI; 1.09, 2.25). When stratified by gender, a similar trend was observed among females (RRR = 2.12, 95%CI; 1.20, 3.73), but not in males. Reduced in-person communication frequency was associated with higher risk of overweight and obesity, especially among females, during COVID-19 in Japan.