Genetic risk and outcome of psychoses (GROUP) is a 6 year longitudinal cohort study that focus on gene–environment vulnerability and resilience in patients with psychotic disorders, their unaffected family members and non-related controls. Its main aim is to elucidate etiological and pathogenetic factors that influence the onset and course of psychotic disorders. In this substudy, we will examine medication use over time, its relation with (the change in) metabolic syndrome status and effects on the brain.

A consortium of four university psychiatric centers and their affiliated mental health care institutions, conducted the GROUP study. At baseline, 1120 patients, 1057 siblings, 919 parents and 590 healthy controls were included. After inclusion, participants, except parents, were evaluated again after three and six years of follow-up. Extensive assessment of genetic factors, environmental factors, medication use, metabolic parameters and outcome were performed. Moreover, brain imaging was performed in a subset of participants, using a 1.5 Tesla MRI scanner.

At baseline 65% of patients used atypical antipsychotics, 16% used conventional antipsychotics and 19% used clozapine. Siblings and controls used no antipsychotics. Forty-three percent of patients, 21.3% of siblings and 9.1% of controls used antidepressants; 43.9% of patients, 2.1% of siblings and none of the controls used a mood stabilizer. We are currently analyzing the medication data over time in relation to (change in) metabolic syndrome status and the effects on the brain.

GROUP is a longitudinal cohort study in patients with psychotic disorders, their healthy siblings and controls without psychosis. This naturalistic substudy examines medication use, its association with (change of) metabolic status and effects on the brain in subjects with (high risk of) psychosis.