"It's kind of just like a never-ending cycle": Young people's experiences of co-existing chronic musculoskeletal pain and mental health conditions.

Chronic musculoskeletal pain (CMP) imposes a significant burden on young people (16-24yrs), impacting their physical, social, and emotional wellbeing and functioning during a critical developmental period as they transition from adolescence to young adulthood. The prevalence of mental health conditions also peaks around this age group, with CMP and mental health conditions being frequently comorbid. Existing epidemiological evidence recognises the relationship as bidirectional; however, there is little in-depth qualitative evidence about how young people experience living with co-existing CMP and mental health conditions. A Constructivist Grounded Theory approach was used. Young people, 16-24 years, living in Australia with self-reported co-existing CMP and mental health conditions were invited to participate in interviews to explore their lived and health care experiences. Twenty-one young people were included (5 men, 1 transgender person, 1 non-binary person, and 14 women). A core category of 'a feedback loop of pain and mental health', characterised the interconnectedness of CMP and mental health in these young people. This feedback loop was influenced both helpfully and unhelpfully by intrapersonal factors (emotions, cognitions, behaviours), interpersonal factors (healthcare interactions, relationships, and sense of self) and their personal context (societal discourse about pain, and mental health including stigma and environmental factors). 'A feedback loop of pain and mental health' suggests the need for a whole person, interdisciplinary approach that is titrated to the needs of the young person and addresses both CMP and mental health concurrently. Further research is needed to test the clinical utility of such a model. PERSPECTIVE: This study highlights the complex bidirectional feedback loop between chronic musculoskeletal pain and mental health in young people aged 16-24. These findings emphasise the need for interdisciplinary, whole-person approaches to concurrently address both conditions. Future research should explore the clinical utility of such models.