Metabolic syndrome in psychiatric patients: overview, mechanisms, and implications

Psychiatric patients have a greater risk of premature mortality, predominantly due to cardiovascular diseases (CVDs). Convincing evidence shows that psychiatric conditions are characterized by an increased risk of metabolic syndrome (MetS), a clustering of cardiovascular risk factors including dyslipidemia, abdominal obesity, hypertension, and hyperglycemia. This increased risk is present for a range of psychiatric conditions, including major depressive disorder (MDD), bipolar disorder (BD), schizophrenia, anxiety disorder, attention-deficit/hyperactivity disorder (ADHD), and posttraumatic stress disorder (PTSD). There is some evidence for a dose-response association with the severity and duration of symptoms and for a bidirectional longitudinal impact between psychiatric disorders and MetS. Associations generally seem stronger with abdominal obesity and dyslipidemia dysregulations than with hypertension. Contributing mechanisms are an unhealthy lifestyle and a poor adherence to medical regimen, which are prevalent among psychiatric patients. Specific psychotropic medications have also shown a profound impact in increasing MetS dysregulations. Finally, pleiotropy in genetic vulnerability and pathophysiological mechanisms, such as those leading to the increased central and peripheral activation of immunometabolic or endocrine systems, plays a role in both MetS and psychiatric disorder development. The excess risk of MetS and its unfavorable somatic health consequences justifies a high priority for future research, prevention, close monitoring, and treatment to reduce MetS in the vulnerable psychiatric patient.