Relationship of work-related and leisure-based screen time with obesity: a cross-sectional study on adults including older adults

PurposeThe relationship between screen time (ST) and obesity has been demonstrated; however, few studies have differentiated between work-related and leisure-based use in Japanese adults, including older adults. This study aimed to examine the relationship between both work-related and leisure-based ST and obesity in adults.MethodsThis cross-sectional study was based on a questionnaire survey conducted in 2018. Overall, 9947 adults were invited; 3161 participants (31.8%) returned the questionnaire. Finally, 2488 participants (597 younger men (YM), 792 younger women (YW), 542 older men (OM), 557 older women (OW)) were included. The main exposures were work-related, leisure-based, and total ST. The outcome was obesity (body mass index >= 25 kg/m2). Log-binomial regression analysis was used to calculate prevalence ratios (PRs) and confidence intervals (CIs) for obesity with 1-h increments of each ST. Analyses were conducted in all participants and subgroups comprising YM, YW, OM, and OW.ResultsTotal ST was significantly associated with obesity in all participants (PR (95% CI) 1.07 (1.04-1.10), YM (1.05 (1.01-1.10)), OM (1.13 (1.05-1.22)), and OW (1.13 (1.02-1.26)). Work-related ST was significantly associated with obesity in all participants (1.08 (1.04-1.12)), YM (1.06 (1.00-1.12)), and OM (1.24 (1.08-1.42)). Leisure-based ST was significantly associated with obesity in all participants (1.09 (1.04-1.14)), YM (1.09 (1.00-1.18)), and YW (1.10 (1.01-1.20)).ConclusionST is associated with obesity in Japanese adults including older adults; particularly, work-related ST is associated with obesity in men, and leisure-based ST, in younger individuals.