Regional differences in treatment response and three year course of schizophrenia across the world.

Data from the Worldwide-Schizophrenia Outpatient Health Outcomes (W-SOHO) study was used to determine the frequency of response and describe the course of disease in outpatients with schizophrenia in different regions of the world. The W-SOHO study was a 3-year, prospective, observational study that included over 17,000 outpatients with schizophrenia from 37 countries classified into six regions (Northern Europe, Southern Europe, Latin America, East Asia, Central & Eastern Europe, North Africa & Middle East). Cox proportional-hazards regression was employed to assess the factors associated with response. Multinomial logistic regression was used to assess the correlates of disease course. We found that approximately two-thirds of the patients (66.4%) achieved response during the 3-year follow up. Response rates varied across regions, and were highest in North Africa & Middle East (84.6%) and Latin America (78.6%) and lowest in Southern Europe (62.1%) and East Asia (60.9%). There were significant differences between the regions in the proportion of patients experiencing continuous remission, remission plus relapse and a persistent symptomatic course, and between the regions in the duration of remission. Overall, Latin America, East Asia, and North Africa & Middle East had more favorable outcomes because they had the largest proportion of people who achieved continuous remission, the longest time in remission and lowest percentage with a persistent symptomatic course. Having good social functioning at baseline was consistently associated with better clinical outcome. These results seem to indicate that patients from Latin America, East Asia, North Africa & Middle East may have a more favorable disease course than patients from European nations.