Chronic pain profile: An interaction between biological and psychosocial factors*

OBJECTIVE: To Identify subgroups of workers with chronic pain based on the interaction of different pain dimensions (sensory, affective, evaluative and mixed), depression, beliefs regarding pain, physical incapacity and socio-demographic-clinical data. METHODS:An observational cross-sectional study was carried out with a convenience sample made up of 115 patients with work-related musculoskeletal disorders (WRMD). The participants answered the McGill Pain Questionnaire, Beck Depression Inventory, Survey of Pain Attitudes, Roland-Morris Disability Questionnaire and a form for socio-demographic and clinical data. RESULTS: Four distinct subgroups were identified, two of which reported pain of a sensory-affective nature and two reported predominantly sensory pain. The individuals in subgroups I and III reported higher levels for all variables analyzed, while the first cluster had the highest mean scores. The subgroup II exhibited moderate degrees of physical disability and a high sick leave index, although the members of this group were less depressed and less dependent upon analgesics. Lower levels of pain, physical disability and depression were associated to subgroup IV, which also had the greatest proportion of males. Beliefs were similar among the subgroups. CONCLUSIONS: Patients with moderate to strong chronic pain associated to sensory and affective components exhibited a higher degree of disability and depression. The results suggest that the chronification process of pain and its functional consequences vary between individuals and are influenced by emotional factors.