Chronic pain and multimorbidity

Objective. To describe the key contemporary challenges in research of multimorbidity where primary and secondary chronic pain are integral components. Material and methods. A narrative literature review enrolled original and review articles in the PubMed and the Russian Science Citation Index databases. We focused on epidemiology, risk factors, clustering and mechanisms of multimorbidity where chronic pain is a component. No formal searching strategy was applied. Results. We analyzed data on the prevalence of multimorbidity in combination with chronic widespread pain, primary and secondary musculoskeletal pain using examples such as fibromyalgia, chronic back pain, osteoarthritis, and rheumatoid arthritis. Analysis highlights associations between multimorbidity and chronic pain with factors like age, gender, socioeconomic conditions, and educational level. Examples of multimorbidity clusters involving chronic pain are provided with emphasis on methodological challenges in characterizing these clusters. Chronic pain in structure of multimorbidity increases overall disease burden, medication load, financial costs, and negatively impacts the quality of life. Additionally, chronic pain often complicates diagnosis. Inclusion of chronic pain in multimorbidity has deepened our understanding of disease complexity and underscored the need for employing machine learning and advanced analytical methods to uncover previously unknown mechanisms driving multimorbidity with chronic pain. Conclusion. Researches should focus on identifying etiological factors underlying multimorbidity associated with chronic pain, exploring genetic and molecular mechanisms of clustering and developing effective, cost-efficient care models. These models should prioritize patient-centered, biopsychosocial approaches to improve the outcomes for individuals with multiple diseases and chronic pain.