A Classification Analysis of Musculoskeletal Complaints and Its Association with Anxiety, Depression and Psychological Distress: Results from a Large-Scale Cross-sectional Study of Adult Iranian Population

Abstract

Objectives: The current study aimed to classify study population in homogenous groups based on musculoskeletal complaints and investigate the association of common psychological disorders with musculoskeletal complaints in a large sample of Iranian adults. Methods: Using data from a cross-sectional sample of adult Iranian population (n = 4762), individuals were classified in meaningful subgroups based on their musculoskeletal complaints and the association of common psychological disorders with musculoskeletal complaints was investigated in identified classes using structural equation mixture model. Musculoskeletal complaints score extracted through eight items concerning site-specific or widespread musculoskeletal symptoms. Psychological distress was measured by General Health Questionnaire (GHQ-12). Depression and anxiety were measured using Persian validated version of the Hospital Anxiety and Depression Scale (HADS). Results: Two classes characterised by high (15.5) and low (84.5) levels of musculoskeletal complaints, were identified using structural equation mixture modeling. All musculoskeletal symptoms had a higher prevalence among participants allocated to 'high musculoskeletal complaints' class compared to 'low musculoskeletal complaints' class. Severe fatigue and back pain were the most reported complaints. Anxiety, depression and psychological distress were positively associated with musculoskeletal complaints score in identified classes, controlling for sex and age. Anxiety showed a stronger association with musculoskeletal complaints score compared to depression and psychological distress. Conclusions: Musculoskeletal complaints can be summarised in a categorical and dimensional structure in the adult study population. Common psychological disorders including anxiety, depression and psychological distress are significantly associated with musculoskeletal complaints. These findings could be useful for dealing with prevention and treatment programmes.