Ashok Malla1,2, Jai Shah1,2, Manish Dama1,2, Srividya Iyer1,2, Ridha Joober1,2, Amal Abdel-Baki3,4, Sherezad Abadi2; 1McGill University, 2Douglas Mental Health University Institute, 3Université de Montréal, 4Centre Hospitalier Universtaire de Montréal
Longer duration of untreated psychosis (DUP) has a negative influence on short and long term outcome in first episode psychosis (FEP) and may limit benefits of specialized early intervention services. It is not clear if this effect would persist even when the early intervention service is extended beyond the initial two years. We report here post-hoc analysis of the results of a large RCT comparing effectiveness of an extended early intervention service (EEIS) to Regular Care, following two years of initial EIS. The results of the principal analyses on the primary outcome (length of positive, negative and total remission) favoured the EEIS. Using a DUP ≤ 12 weeks (as per the literature) cut-off 217 patients were split into two groups and examined if longer remission in patients randomized to an EEIS was associated with shorter DUP. Patients with DUP ≤ 12 weeks (median for the sample), treated in an extended EIS experienced significantly longer remission for positive (β = 0.35; p <0.01), negative (β = 0.38; p <0.01), and total symptoms (β = 0.36; p = 0.01) compared to regular care. However, for patients with DUP > 12 weeks, no such difference emerged between the two treatment conditions. For those with DUP between 12-24 weeks, only length of remission for positive symptoms (but not negative) showed a borderline significance (β = 0.37; p = 0.05). These findings suggest that reducing DUP may be essential to getting the most benefit from a specialized EI service even in an extended EI service.
