Accumulation of psychosocial and lifestyle factors and risk of low back pain in adolescence: a cohort study.

Purpose: Low back pain (LBP) is common already in adolescence, and many risk indicators including both psychosocial and lifestyle factors have been recognized. Our purpose was to assess whether the co-occurrence of psychosocial (externalizing and internalizing) problems and lifestyle factors (leisure time physical activity, sedentary behaviour, sleep, smoking, and overweight/obesity) associate with LBP at 16 years cross-sectionally or with new LBP at 18-year follow-up.

Methods: The study population, drawn from the Northern Finland Birth Cohort 1986, consisted of 1625 participants (712 boys and 913 girls) who completed a questionnaire on potential explanatory factors at 16 years and on LBP at 16 and 18 years. The outcome measure was 'reporting LBP' or 'consultation for LBP' during the past 6 months. Latent Class Analysis (LCA) was utilized to study the co-occurrence of the explanatory factors.

Results: Among both genders, four clusters were found. Externalizing behaviour problems were associated with 'reporting LBP' (RR 1.5, boys 1.4, girls) and 'consultation for LBP' (RR 1.6 for both genders) at baseline among both genders. In addition, the cluster of multiple risk behaviours was associated with both 'reporting LBP' (RR 1.3) and 'consultation for LBP' (RR 2.5) and the obese cluster with 'consultation for LBP' (RR 1.7) among girls. Externalizing behaviour problems at 16 years predicted 'consultation for LBP' at 18 years among girls (RR 3.6).

Conclusions: Our results stress the role of psychosocial factors in reporting and seeking care for adolescent LBP.