Associations between adherence to 24-h movement guidelines and non-suicidal self-injury in adolescents: separate moderation by sex and mediation by psychological health.
Adolescent non-suicidal self-injury (NSSI) is a growing public health concern. Adherence to 24-h movement guidelines yields notable health benefits, yet no studies have explored its association with adolescent NSSI. This study examined this association, alongside the moderating effect of sex and mediating role of psychological health (PH).
A total of 4,205 adolescents from five central Chinese cities were recruited. Self-reported questionnaires assessed sociodemographic characteristics, moderate-to-vigorous physical activity (MVPA), screen time, sleep duration, NSSI, and PH. Logistic regression analyzed associations between 24-h movement guideline adherence and NSSI; sex moderation was tested via interaction terms, and PH mediation via the PROCESS macro.
NSSI prevalence was 35.29%, while only 1.28% adhered to all three guidelines. Compared with adherence to none, meeting more guidelines was associated with progressively lower NSSI odds [1 vs 0: OR = 0.72, 95% CI (0.62, 0.83); 2 vs. 0: OR = 0.44, 95% CI (0.36, 0.54); 3 vs. 0: OR = 0.31, 95% CI (0.15, 0.65)]. However, adherence to three guidelines did not significantly further reduce risk vs. two [OR = 0.72, 95% CI (0.34, 1.49)]. Among equivalent adherence levels, combinations including the sleep guideline were associated with lower NSSI than those without (p < 0.05). Isolated MVPA guideline adherence showed no association with NSSI [OR = 1.15, 95% CI (0.74, 1.80)]. Sex significantly moderated the association for two guidelines and the "screen + sleep" combination (p < 0.05), with stronger negative associations in girls. PH significantly mediated the relationship.
Promoting adherence to 24-h movement guidelines, particularly the sleep guideline, may help manage adolescent NSSI risks, with emphasis on PH promotion and attention to sex differences.
A total of 4,205 adolescents from five central Chinese cities were recruited. Self-reported questionnaires assessed sociodemographic characteristics, moderate-to-vigorous physical activity (MVPA), screen time, sleep duration, NSSI, and PH. Logistic regression analyzed associations between 24-h movement guideline adherence and NSSI; sex moderation was tested via interaction terms, and PH mediation via the PROCESS macro.
NSSI prevalence was 35.29%, while only 1.28% adhered to all three guidelines. Compared with adherence to none, meeting more guidelines was associated with progressively lower NSSI odds [1 vs 0: OR = 0.72, 95% CI (0.62, 0.83); 2 vs. 0: OR = 0.44, 95% CI (0.36, 0.54); 3 vs. 0: OR = 0.31, 95% CI (0.15, 0.65)]. However, adherence to three guidelines did not significantly further reduce risk vs. two [OR = 0.72, 95% CI (0.34, 1.49)]. Among equivalent adherence levels, combinations including the sleep guideline were associated with lower NSSI than those without (p < 0.05). Isolated MVPA guideline adherence showed no association with NSSI [OR = 1.15, 95% CI (0.74, 1.80)]. Sex significantly moderated the association for two guidelines and the "screen + sleep" combination (p < 0.05), with stronger negative associations in girls. PH significantly mediated the relationship.
Promoting adherence to 24-h movement guidelines, particularly the sleep guideline, may help manage adolescent NSSI risks, with emphasis on PH promotion and attention to sex differences.