Objective

Few data are available to inform clinical expectations about course and prognosis of severe obsessive-compulsive disorder (OCD). Such information is necessary to guide clinicians and to inform criteria for invasive interventions for severe and intractable OCD. This study sought to examine course and prospective predictors of a chronic course in patients with severe OCD over 5 years.

Method

A selected subset of adults in the Brown Longitudinal Obsessive-Compulsive Study (BLOCS) was included. Adult BLOCS participants were enrolled between 2001 and 2006. All participants in the current study (N = 113) had DSM-IV OCD diagnosis, severe OCD symptoms at baseline, and at least 1 year of follow-up data.

Results

Cox proportional hazard models were used to examine the general pattern of course in the severe OCD sample based on Longitudinal Interval Follow-Up Evaluation (LIFE) psychiatric status ratings, as well as test predictors of chronically severe course. Results indicated that approximately half of patients with severe OCD at baseline had illness drop to a moderate or lower range of severity during 5 years of follow-up (50.4%) and that marked improvement was rare after 3 years of severe illness. The only unique predictor of a more chronically severe course was patient report of ever having been housebound for a week or more due to OCD symptoms (P < .05).

Conclusions

Findings of this study were 3-fold: (1) half of participants with severe OCD have symptom improvement over 5 years of follow-up, (2) the majority of participants that drop out of the severe range of symptom severity do so within the first 3 years of follow-up, and (3) patient-reported history of being housebound for 1 week or more due to OCD is a significant predictor of OCD's remaining severe over the 5-year follow-up.

Obsessive-compulsive disorder (OCD), a leading cause of disability, affects ~1-2% of the population, and can be distressing and disabling. About 1/3 of individuals demonstrate poor responsiveness to conventional treatments. A small proportion of these individuals may be deep brain stimulation (DBS) candidates. Candidacy is assessed through a multidisciplinary process including assessment of illness severity, chronicity, and functional impact. Optimization failure, despite multiple treatments, is critical during screening. Few patients nationwide are eligible for OCD DBS and thus a multi-center approach was necessary to obtain adequate sample size. The study was conducted over a six-year period and was a NIH-funded, eight-center sham-controlled trial of DBS targeting the ventral capsule/ventral striatum (VC/VS) region. There were 269 individuals who initially contacted the sites, in order to achieve 27 participants enrolled. Study enrollment required extensive review for eligibility, which was overseen by an independent advisory board. Disabling OCD had to be persistent for ≥5 years despite exhaustive medication and behavioral treatment. The final cohort was derived from a detailed consent process that included consent monitoring. Mean illness duration was 27.2 years. OCD symptom subtypes and psychiatric comorbidities varied, but all had severe disability with impaired quality of life and functioning. Participants were randomized to receive sham or active DBS for three months. Following this period, all participants received active DBS. Treatment assignment was masked to participants and raters and assessments were blinded. The final sample was consistent in demographic characteristics and clinical features when compared to other contemporary published prospective studies of OCD DBS. We report the clinical trial design, methods, and general demographics of this OCD DBS sample.