Predictors of outcome in early onset schizophrenia: a 10-year follow-up study

Abstract

Background: Younger age at onset is generally thought to be a predictor of poor outcome in Early Onset Schizophrenia (EOS), but there is a paucity of epidemiological data supporting this belief. This study aims to describe long-term outcomes and predictors of patient functioning in EOS, with a focus on the effect of age at onset.

Methods: We consecutively enrolled 118 EOS patients who were hospitalized in 2006. Mean age at baseline was 13.3 ± 2.3 years. Sixty-five subjects were successfully interviewed. Mean length of follow up was 10.4 ± 0.3 years. Baseline data were collected from inpatient medical records, while follow up was conducted primarily through telephone interviews of patient relatives. WHODAS 2.0 was used to measure global functioning at follow up. Outcomes included education, employment, marriage status, physical health, subsequent diagnoses and treatment, and patient functioning. Univariate and multivariate regression models were used to assess predictors of outcome, while propensity scores were used to adjust for confounding in analyzing the effect of age at onset on functional outcome.

Results: Of the 65 subjects where follow-up data were available, 3 were deceased at follow up. Five (8%) discontinued treatment. Diagnostic stability was 76%. Nearly a quarter (24%) were using clozapine at follow up. In male and female patients, 61 and 55% respectively were overweight, while 29 and 32% respectively were obese. Sixteen (26%) were economically self-sufficient, while 34 (55%) were unemployed. Thirteen (21%) patients had ever been married. The median WHODAS score was 15 (IQR 2 to 35), roughly corresponding to the 78th percentile on population norms. Extroverted personality (p = 0.01), suspicious personality (p = 0.02), and high level of education (p = 0.001) predicted better functioning. Age of onset was not associated with function in either the univariate model (p = 0.24), full model (p = 0.17) or the final risk factor model (p = 0.11), nor after using propensity scores to further adjust for confounders.

Conclusion: The long-term functional outcome of EOS is more optimistic than generally believed. Age at disease onset does not predict long-term functional outcome in EOS populations.

Keywords: Early onset schizophrenia; Follow-up; Patient function.

Fig. 1

Change in antipsychotic medication prescription from baseline to follow up. On the horizontal axis is antipsychotic drug type, arranged in descending order from left to right by frequency of use at baseline. Data shown is the proportion of patients using each drug at baseline and follow up. Each patient could have been using multiple drugs.