[Prospective follow-up over a 12 month period of a cohort of 155 patients with obsessive-compulsive disorder: phase III National DRT-TOC Study].

In the phase III of the french national study on OCD, 155 patients suffering from an OCD (full DSM III-R criteria, score on NIMH-OC > or = 7, not treated or undertreated) had entered a naturalistic follow-up of 12 months duration. Obsessions, compulsions, depression, anxiety, impulsivity and global functioning were assessed by using NIMH-OC, CPRS-OC2, MOCI, MADRS, HAD (-A, -D), BDS (Behavioral Dyscontrol Scale), CGI and GAS (DSM III-R). From the initial population (155 patients), 130 (84%) had been treated with drugs and were "completers" and assessed at M6 and M12; 18 (11.6%) were lost to follow-up and 7 (4.5%) had dropped out because of treatment refusal, side-effect or improvement. Only 19% of patients had received a behavior therapy. In spite of selection of patients with severe and chronic OCD associated to depression (mean MADRS score = 25), 85% of treated patients had been treated with one anti-OCD drug (105 with fluoxetine, 17 with clomipramine and 17 with other antidepressants), 4.5% needed a treatment substitution and 4.5% a bitherapy (combination of 2 anti-OCD drugs); 84% of patients were considered as "good compliant" with visit agenda and treatment. At the end of follow-up, global improvement was observed in 77% of patients treated. Clinical improvement was assessed by different response criteria (final NIMH-OC score, 30% decrease on NIMH-OC, 35% decrease on MOCI, final GAF score > or = 70) which showed 4 patterns of response to treatment: "positive response on M6 and M12" = 43-64%; "only M12" (slow response) = 13-24%; "only M6" (escape or relapse) = 4-6%; "negative response on M6 and M12" (resistant OCD) = 19-33%. During 12 month treatment, 31 patients (22.5%) had presented an adverse effect in which 7 cases (5.1%) with "serious adverse event" and 5 cases (3.6%) who required treatment drop-out. Predictive factors of clinical response to anti-OCD drugs were explored: 1) "lack of insight" was the best factor to characterise the resistant group; 2) high base-line of "impulsivity" predict better response at M6; 3) important to severe slowness was associated with a longer delay to response (between M6 and M12). The results of the phase III from the french multi-site study will be compared to the international data on long-term treatment of OCD.