Eur J Pain. 2026 Feb;30(2):e70217. doi: 10.1002/ejp.70217.
ABSTRACT
BACKGROUND: Chronic pain frequently co-occurs with multiple somatic comorbidities. However, little is known about how these conditions naturally cluster in patients with high-impact chronic pain. This study aimed to describe somatic comorbidities and identify clusters of co-occurring diseases in patients with high-impact chronic pain referred to specialised interdisciplinary treatment and to examine associations between these clusters and patient-reported physical health, mental health and pain distribution.
METHODS: A cross-sectional study was conducted with 10,256 chronic pain patients referred to specialised interdisciplinary pain treatment using data from the Danish PainData registry. Somatic comorbidities were self-reported from a list of 16 diseases and conditions. Exploratory factor analysis with tetrachoric correlations identified clusters of comorbidities. Physical and mental health were evaluated using the PROMIS-10 Global Health questionnaire and pain distribution was assessed by a 71-area pain drawing. Statistical analyses, including ANOVA and Kruskal-Wallis tests, evaluated differences in patient-reported outcomes between disease clusters.
RESULTS: Patients reported a median of three somatic comorbidities, with migraine (56%), herniated disc/spinal disorders (53%) and osteoarthritis (42%) being most prevalent. Factor analysis revealed six disease clusters, including systemic illness, cardiovascular disease, musculoskeletal disorders, metabolic-vascular conditions, allergy-respiratory issues and neurosensory disturbances. Distinct clusters of co-occurring diseases and conditions were associated with poorer physical health and more widespread pain.
CONCLUSIONS: Somatic comorbidities were highly prevalent in this large chronic pain cohort, with six disease clusters associated with varying levels of physical health and pain distribution. These findings highlight the need for stratified approaches in pain care, informed by somatic disease clustering.
SIGNIFICANCE STATEMENT: This study identifies distinct clusters of somatic comorbidities among patients with high-impact chronic pain and links them to health outcomes. Understanding these clusters may help clinicians tailor more precise, stratified pain interventions and offers basic scientists insight into potential underlying mechanisms connecting chronic pain with systemic disease patterns.
PMID:41615244 | DOI:10.1002/ejp.70217