Predictors of medium and long-term outcome following capsulotomy for obsessive-compulsive disorder: one site may not fit all

Patients with treatment-refractory obsessive-compulsive disorder (OCD) are sometimes considered for surgical interventions. The identification of reliable predictors of outcome following such interventions would be of great clinical importance, as it would lead to stricter selection of suitable patients, thus avoiding unnecessary surgery and improving the overall response rate. We analyzed data from 24 severe treatment-resistant patients who underwent capsulotomy for OCD and were carefully followed-up one year after the surgery and at long term (mean 10.8 years after surgery). The Yale-Brown Obsessive Compulsive Scale Symptom Checklist was administered to assess the lifetime presence of the most common symptom types. We applied an algorithm to calculate the patients' scores on 4 well-established symptom dimensions: Contamination/cleaning, forbidden thoughts, symmetry/order and hoarding. Multiple regression models were employed to examine whether scores on certain symptom dimensions were predictive of long-term outcome. The presence and number of lifetime symptoms in the symmetry/order domain were associated with greater severity of OCD, depression and anxiety, as well as greater impairment in various functional domains like work, social and family life at both one-year and long-term follow-ups. These results remained consistently significant after controlling for preoperative psychopathology, scores on other OCD symptom dimensions, sex, age, age of onset, duration of follow-up, type of surgical procedure, number of operations and lesion volume. The results could have implications for existing ablative and deep brain stimulation protocols and challenge our current conceptualization of OCD as a unitary diagnostic entity with a single neurobiological substrate.