Changes in Body Mass Index During Mandatory Forensic Psychiatric Care: Findings from a Long-Term (2009-2020) Cohort Study Based on Swedish Registry Data

Lifespan is reduced by approximately 15 years in individuals suffering from severe mental illnesses such as schizophrenia spectrum disorders. Contributing to this is an increased prevalence of metabolic syndrome, an assortment of factors that confer risk of diabetes type 2 and cardiovascular disease. Body Mass Index (BMI) is predictive of metabolic syndrome. Previous research indicates that the BMI of incarcerated individuals not suffering from a major mental disorder increase during incarceration, especially amongst females. However, information on the development of BMI during forensic psychiatric care is scarcer, and follow-up periods have been short. Thus, the authors extracted data from the Swedish National Forensic Psychiatric Register regarding the longitudinal development of BMI in 3389 individuals who received court mandated forensic psychiatric care in Sweden during 2009-2020. A significant increase in BMI by 1.1% per year was observed during the first four years of care. After this, changes were no longer significant. Factors associated with a larger increase in BMI were female gender, being prescribed antipsychotics, young age at admission, receiving outpatient care, and access to an external support person. There was an inverse association between BMI and symptom severity. Substantial heterogeneity was observed in longitudinal changes in individual BMI and in comparisons between individuals receiving care at different clinics.