Musculoskeletal pain latent classes and biopsychosocial characteristics among emerging adults.

Background: Emerging adults (aged 18-29) report high levels of musculoskeletal pain; however, it is unknown if body location and intensity patterns are related to different biopsychosocial characteristics. This study identified patterns of self-reported musculoskeletal pain among emerging adults and assessed if there were differences in their lifestyle and psychological characteristics.

Methods: Data from survey responses from a large public university and a large medical university in the United States were used (n = 1,318). Self-reported pain location and intensity at five body regions were assessed, and latent class analysis identified classes separately for men and women. Mental health, physical activity, and sleep outcomes were compared between the classes.

Results: Four classes were identified for men and women. Three of the classes were consistent between genders - "no pain," (women = 28% of their sample; men = 40% of their sample) "mild multisite pain," (women = 50%; men = 39%) and "moderate-severe multisite pain" (women = 9%; men = 7%). The fourth class for women was "moderate spine pain," (13%) and for men was "mild extremity pain" (13%). For both men and women, the "moderate-severe multisite" pain classes reported the highest levels of depression, anxiety, and stress, poorer sleep, and higher work physical activity than the "no pain" class. The "mild multisite" and "moderate spine" (women only) pain classes fell between the "no pain" and "moderate-severe" pain classes. The characteristics of the "mild upper extremity pain" class for men was similar to the "no pain" class.

Conclusions: The identified classes provide unique information on pain location and intensity in emerging adults. The high prevalence of "mild multisite pain" (n = 593; 45% of the total sample) demonstrates an intervention opportunity during this age range to prevent further increases in musculoskeletal pain later in life. Future work should assess the longitudinal outcomes of these pain classes, the impact of interventions for this age group, and the balance between leisure and occupational physical activity when addressing musculoskeletal health.