Is Schizophrenia a Progressive Disease?
Robert B. Zipursky, M.D.
Professor and Chair
Department of Psychiatry and Behavioural Neurosciences
Clinicians generally think of Schizophrenia as a progressive illness, beginning early in life with psychotic episodes in adolescence and the early twenties, and resulting in a state of disability. Yet these assumptions may be incorrect. Reasons for the assumption that Schizophrenia is a progressive disease may include the ‘clinician’s illusion’, which is the attribution of the characteristic and course of those patients who are currently ill to the entire population contracting the illness. Another component that may contribute to the assumption of progression is Berkson’s fallacy, the idea that those who have other disabilities that are not causally connected to the condition being investigated are more likely to enter the formal treatment system, and that these etiologically unrelated conditions may have a negative influence on the course of the illness. A longitudinal study found that the best predictor for a long-term successful outcome is the patient’s treatment success in the first two years of the illness. Thus, there is no reason to believe that the percentage of those doing poorly increases over time. Conclusions emphasized the following: there is little evidence that there is substantial progression of the disease, most remitted patients remain well with going treatment, short-term course predicts long-term outcome, the percentage of patients with a poor outcome remains stable over time, and many patients can be symptom free and obtain employment. The reasons why patients do poorly can be due to premorbid deficits, concurrent disorders, extended period of the disability before treatment, limited access to necessary interventions, non-adherence with resulting relapses, and a downhill spiral due to stigma, poverty, homelessness, and unemployment. Clinicians must work hard to intervene in ways that are known to be effective.