Psychological processes underlying the development of a chronic pain problem: a prospective study of the relationship between profiles of psychological variables in the fear-avoidance model and disability.
OBJECTIVE
Understanding the psychological processes that underlie the development of a chronic pain problem is important to improve prevention and treatment. The aim of this study was to test whether distinct profiles of variables within the fear-avoidance model could be identified and could be related to disability in a meaningful way.


METHODS
In 81 persons with a musculoskeletal pain problem, cluster analysis was used to identify subgroups with similar patterns on fear and avoidance beliefs, catastrophizing, and depression. The clusters were examined cross-sectionally and prospectively on function, pain, health care usage, and sick leave.


RESULTS
Five distinct profiles were found: pain-related fear, pain-related fear + depressed mood, medium pain-related fear, depressed mood, and low risk. These subgroups were clearly related to outcome. In contrast to the clusters "medium pain-related fear" and "low risk," the majority of those classified in the clusters "pain-related fear," "pain-related fear + depressed mood," and "depressed mood" reported long-term sick leave during follow-up. The subjects in the clusters with high scores on the depression measure reported the highest percentage of health care usage during follow-up (70% in the "pain-related fear + depressed mood" group and 42% in the "depressed mood" group reported >10 health care visits).


CONCLUSIONS
Distinct profiles of psychological functioning could be extracted and meaningfully related to future disability. These profiles give support to the fear-avoidance model and underscore the need to address the psychological aspects of the pain experience early on.
Boersma
Katja
K
Department of Occupational and Environmental Medicine, Orebro University Hospital, Orebro, Sweden. katja.boersma@orebroll.se
Linton
Steven J
SJ
D000223:Adaptation, Psychological; D000328:Adult; D002908:Chronic Disease; D016000:Cluster Analysis; D003469:Culture; D003863:Depression / Q000523:psychology; D004185:Disability Evaluation; D005239:Fear / Q000523:psychology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009140:Musculoskeletal Diseases / Q000453:epidemiology / Q000523:psychology; D010146:Pain / Q000453:epidemiology / Q000523:psychology*; D010147:Pain Measurement; D011446:Prospective Studies; D011569:Psychiatric Status Rating Scales; D015203:Reproducibility of Results; D018582:Sick Leave; D011795:Surveys and Questionnaires; D013548:Sweden / Q000453:epidemiology