Continuous chronic musculoskeletal pain and its associated sociodemographic, psychosocial, and behavioral factors among adolescents living in a socially vulnerable urban setting in northeastern Brazil

Background Chronic musculoskeletal pain is common during adolescence, yet evidence from socially disadvantaged populations in low- and middle-income countries remains limited. This study investigated the occurrence of continuous chronic musculoskeletal pain and its associated sociodemographic, psychosocial, and behavioral factors among adolescents living in a socially vulnerable urban setting in northeastern Brazil. Methods An analytical cross-sectional study was conducted with 296 adolescents aged 14–18 years from five public secondary schools in northeastern Brazil. The study area was characterized by socioeconomic deprivation, a Human Development Index below 0.499, and high levels of violence. Musculoskeletal pain was assessed using the validated Presence and Impact of Pain in Kids questionnaire, with continuous pain lasting more than three months considered the outcome. Anxiety and depressive symptoms, sleep quality, physical activity, school bullying, family violence, self-rated health, healthcare provision, and daily smartphone use were assessed using standardized instruments and structured questionnaires. Bivariate analyses and multivariable binary logistic regression were performed to estimate crude and adjusted odds ratios. Results 31.4% adolescents reported continuous chronic musculoskeletal pain. In the final adjusted model, poor sleep quality was associated with higher odds of pain (aOR=2.49; 95% CI: 1.04–5.97; p = 0.041), as were anxiety symptoms (aOR=1.93; 95% CI: 1.02–3.63; p = 0.042). Each additional hour of daily smartphone use was associated with an 8.8% increase in the odds of pain (aOR=1.09; 95% CI: 1.02–1.16; p = 0.011). Conclusion Continuous chronic musculoskeletal pain was reported by nearly one-third of adolescents attending public schools in a socially vulnerable urban setting. Its associations with anxiety, poor sleep quality, and longer smartphone use reinforce the multidimensional nature of adolescent pain. These findings expand evidence from an underrepresented Brazilian population and support context-sensitive approaches integrating pain, mental health, sleep, and everyday behaviors within school and primary healthcare settings.