The longitudinal course of schizophrenia: testosterone and progression of the negative symptoms

Background: The longitudinal course of schizophrenia shows a high level of heterogeneity with testosterone as a possible factor in the variety of clinical outcomes.Aim: Evaluation of the course of schizophrenia in male patients over an eight-year period and of the possible testosterone effects on changes in clinical features.Subjects and methods: The initial study population consisted of 120 male schizophrenic patients (aged 18-40) hospitalized in the University Psychiatric Hospital Vrapce in 2009. Patients were classified into nonaggressive (control, n = 60) and aggressive (n = 60) groups. In 2017, we reassessed 85 patients (67,5%) from the initial sample. Symptoms of schizophrenia were determined using the Positive and Negative Syndrome Scale (PANSS) and compared with the total serum testosterone level taken at the inclusion in the study. The distribution of values for individual variables was determined using the Smirnov-Kolmogorov test; for all further analyses, the appropriate non-parametric test was used.Results: The control group showed a statistically significant negative correlation between testosterone and negative PANSS. The initial PANSS scores, compared to those at the follow-up, showed a statistically significant reduction in positive and general symptoms in all groups, with the greatest reduction in the control group.Conclusion: We found a reduction in positive and general symptoms of schizophrenia among all patients and no changes in negative symptoms. Inverse correlation between testosterone and negative symptoms was found only in the control group, but there was no testosterone influence on the progression of any PANSS subscales.