Chronic Pain and Obsessive-Compulsive Disorder: A Scoping Review.

Introduction: The aim of this study was to map the association between Chronic Pain (CP) and Obsessive-Compulsive Disorder (OCD) in the present literature.

Methods: A scoping review was conducted with a comprehensive search of literature in peer-reviewed journals. Search parameters included articles written in English, published at any time, and including terms associated with both CP and OCD. Databases searched for purposes of this study included Psychinfo, Medline, Embase, Emcare, CINAHL, Scopus, Web of Science, Cochrane, and Google Scholar.

Results: The review included 87 records, comprising 49 primary research and 38 secondary research records. Extracted information from these were grouped into four broad classifications. The Prevalence and Severity classification included information from 39 records which comprised: (1) primary research detailing current OCD prevalence rates in CP conditions (differentiated between general population and Pain/Medical/Hospital clinics); (2) primary research detailing lifetime OCD prevalence rates in CP conditions; (3) primary research detailing CP prevalence rates in OCD; (4) primary research detailing relationships between OCD and CP through psychometric measures; and (5) secondary research relating to prevalence rates. The Neurobiology classification included information from 28 records (primary and secondary research) detailing convergent and divergent neurobiological/neurophysiological aspects as reported for both OCD and CP. The Psychological Models/Factors classification included information from 7 records (primary and secondary research) detailing pain-related anxiety, neuropsychological measures, catastrophic thinking, preservative thinking, early maladaptive schemas, schema modes, childhood trauma experiences, and conditional associative learning, as reported for OCD and CP. The Intervention classification included information from 32 records which comprised: (1) primary research on neurosurgical, medication, and psychotherapeutic interventions; (2) secondary research on Deep Brain Stimulation; (3) secondary research on Medication; (4) secondary research on lesion, cingulotomy, and other surgical procedures; and (5) secondary research on other interventional procedures.

Conclusion: While there has been considerable and growing research in the fields of both OCD and CP over the years, focused research into their potential association has been limited and potentially overlooked. The results of this review, however, suggest a complex relationship between CP and OCD. Prevalence rates between the two conditions vary widely across different populations, although the underlying reason for this remains unclear at this stage. There are commonalities in terms of alterations in pain processing, the dysregulation of certain brain regions, and the abnormalities in neurotransmitter systems in both conditions. In their treatment, use can be made of overlapping pathophysiological processes, the convergent and divergent psychological aspects, and the range of interventional approaches that share targets to promote efficacy. However, the complex presentations of both OCD and CP make it a challenging relationship to accurately clarify. Further directed and robust, high-quality studies will be needed to expand our understanding of this area.