Strong clinical evidence exists to support the existence of an association between mental illness and non-alcoholic fatty liver disease (NAFLD). It is known that NAFLD is highly comorbid with psychiatric illness, and patients with bipolar disorder and schizophrenia possess increased prevalence of metabolic liver disease. Recent studies have thus indicated that patients with mental illness may possess a unique, increased risk of developing NAFLD.
Despite this, the mechanisms underlying the relationship between NAFLD and mental illness have not yet been clearly defined, and guidelines for the treatment of NAFLD in psychiatry have not been developed.
This review aims to investigate the main contributors to the development of NAFLD in patients with mood disorders.
Patients with mood disorders are at a higher risk of developing NAFLD and non-alcoholic steatohepatitis (NASH). Factors contributing to this increased risk include genetic susceptibility, socioeconomic factors, insulin resistance, systemic inflammation, and psychiatric medications.
Social and environmental factors in particular greatly influence NAFLD incidence in this patient population. Socioeconomic factors contributing to NAFLD development include sedentary lifestyles, high fat diets, smoking, and food insecurity. Psychotropic medications, such as SSRI antidepressants and atypical antipsychotics (AAs), also confer patients with an increased risk of developing NAFLD. Both SSRI antidepressants and AAs alter body weight and metabolism, and AAs have been shown to cause rapid and significant weight gain and insulin resistance. Patients taking these medications thus possess a high risk of developing metabolic liver diseases like NAFLD.
These findings highlight the importance of defining relative NAFLD risk for classes of psychiatric drugs and emphasize the key role of combination therapies focused on reducing psychotropic medication-associated metabolic risk.