Impact of clozapine on disability and course of illness in patients with schizophrenia: A study from North India

Abstract

Aim: The aim of this study was to evaluate the impact of long-term use of clozapine on disability and course of illness among patients with treatment-resistant schizophrenia. Materials and Methods: 102 participants who have been receiving clozapine for a mean duration of 5 years were evaluated on Positive and Negative Syndrome Scale (PANSS) rating, Clinical Global Impression (CGI) severity rating, and Indian Disability Evaluation and Assessment Scale (IDEAS) and the scores were compared with the scores on the same scales at the time of starting clozapine. Results: There was a significant reduction in both CGI-severity scores and scores in all the four domains of IDEAS, alongside a significant reduction on all three subscales of PANSS with clozapine treatment. The CGI global improvement subscale was rated as very much improved for 80 patients. In terms of course of symptoms, at 6 months of clozapine use, three-fourth of the patients were rated as having partial recovery with no relapse of symptoms, but with passage of time, the proportion of patients in the category of 'complete recovery' was found to be increasing. Higher CGI severity at the follow-up, lower CGI global improvement, and poorer efficacy index were associated with higher disability at the follow-up. Conclusions: The present study suggests that clozapine has a significant beneficial impact on disability and course of illness among patients with treatment-resistant schizophrenia.