Sleep disorders in patients with schizophrenia: correlations with metabolic syndrome and schizophrenia symptoms

Introduction: The purpose of this research is to evalu-ate sleep disturbances in people with schizophrenia and to analyse correlations between sleep disorders, pres-ence of metabolic syndrome and negative symptoms of schizophrenia. Material and methods: The research group was com-posed of 46 patients: 24 men and 22 women, all of whom had been diagnosed with schizophrenia and were not younger than 18 years. Using an actigraph the following sleep parameters were monitored: sleep efficiency, total time in bed, total sleep time, number of awakenings and length of awakenings. To assess negative symptoms of schizophrenia three scales were used: PANSS (Positive and Negative Syndrome Scale), BNSS (Brief Negative Syndrome Scale) and SNS (Self-evaluation of Negative Symptoms). Results: Significant differences regarding sleep param-eters were not observed between the group with meta-bolic syndrome and the group without metabolic syn-drome. No significant correlations were found between sleep parameters and total PANSS score, total BNSS score, total SNS score and PANSS subscales. Correla-tions between sleep parameters and single PANSS and SNS items were reported. Conclusions: More multicentre research on a larger group of patients is required to confirm the obtained results.