Behavioral outputs of negative symptom domains of schizophrenia.

The present study aimed to validate the hypothesis that negative symptoms of schizophrenia encompass two domains, namely avolition-apathy (AA) and diminished expression (DE), and to investigate the relationship of these domains with behavioral outputs which imply hedonic activities: Cigarette use and weight gain. A total of 106 consecutive schizophrenia outpatients with primary negative symptoms were evaluated using the Positive and Negative Syndrome Scale (PANSS), the Negative Symptoms Assessment Scale (NSA-16), the Calgary Depression Scale for Schizophrenia (CDSS), and the Simpson-Angus Scale (SAS). A semi-structured interview was used to assess demographic features, the number of cigarettes smoked per day, and body mass index. Data were analyzed using descriptive statistics, principal component analysis, analysis of variance, and covariance. A two-factor solution was revealed for the negative symptoms of schizophrenia represented by AA and DE. Analyses of variance and covariance suggested that higher AA scores were associated with normal weight and non-smoking status. No significant differences were revealed regarding DE scores in relationship with the same behavioral hedonic outputs. The present results indicated the AA and DE domains exhibit meaningful differences concerning the outcome, which may imply the need for different approaches regarding rating and treatment.