Overview of Managing Medical Comorbidities in Patients With Severe Mental Illness

Roger S. McIntyre, MD, FRCPC

Department of Psychiatry and Pharmacology, University of Toronto, and the Mood Disorders Psychopharmacology Unit, University Health Network, Toronto, Ontario, Canada

Increased Mortality in Severe Mental Illness


People with serious and persistent mental disorders, particularly schizophrenia and bipolar disorder, have higher rates of mortality than would be expected in an otherwise healthy population.1,2 Multiple factors contribute to the increased mortality of people with mental disorders, some of which are independent and some of which are interdependent. Patients with bipolar disorder or schizophrenia often do not have access to optimal primary care and make poor decisions regarding diet and lifestyle, which can increase the incidence of several somatic comorbidities, including, but not limited to, metabolic syndrome, diabetes, and cardiovascular disease (CVD), which causes more deaths in the severely mentally ill than any other factor (AV 1AV 1).2 In addition, the medications used to treat mental disorders can have adverse effects that are themselves risk factors for mortality. For instance, some second-generation antipsychotics can cause weight gain, which in turn contributes to the potential development of a host of related medical conditions. Many of the health problems associated with high mortality in patients with severe mental illness could potentially be addressed by integrating psychiatric care and primary care.3 Although psychiatrists should not serve as primary care physicians, they should take the lead in coordinating psychiatric care with general medical care and educate patients about healthy habits. The development and dissemination of professional guidelines would be helpful in this area.

The Patient’s Perspective on Mental Illness and Medical Comorbidities

The high incidence of somatic comorbidities occurring with serious mental disorders and the associated increased rates of mortality are well documented. However, little information has been available regarding the knowledge that patients and their caregivers have about the relationship between persistent mental illness and comorbid somatic conditions. Participants in the Understanding Patients’ Needs, Interactions, Treatment, and Expectations (UNITE) survey, a global survey of patients with schizophrenia or bipolar disorder and their families that attempted to ascertain the patient perspective on mental illness and its treatment, reported high rates of disability but attributed a significant portion of their burden of illness to the somatic conditions concurrent with their psychiatric disorders.4 Participants were knowledgeable about the interaction between somatic and psychiatric disorders, particularly when it came to issues of weight gain associated with psychotropic medication and the related risks of CVD, diabetes, and other conditions. However, survey participants reported that relatively little discussion regarding medical issues took place during their interactions with their health care providers. Patients were not advised of what they could do to manage risk factors, such as smoking cessation, dietary choices, and general behavioral modification. In short, the UNITE survey uncovered a disconnect between what patients and their caregivers know about the relationship between mental illness and comorbid somatic conditions and what they know about preventing or managing medical problems.


The Relationship Between Mental Illness and Associated Medical Conditions

High rates of obesity, metabolic syndrome, diabetes, and CVD in the mentally ill are well established, but the causal relationships between psychiatric illnesses and comorbid somatic conditions are unclear.5 In the case of bipolar disorder and obesity, evidence suggests that obese patients with bipolar disorder have more manic and depressive episodes,6 more severe episodes with longer duration,6 shorter time to recurrence,6 increased suicidality,7 and poorer outcomes6 than patients with bipolar disorder who are not obese. Conversely, the presence of bipolar disorder might increase the likelihood that a patient will become obese owing to decreased levels of physical activity, unhealthy diet, and other factors, and the treatment of bipolar disorder with atypical antipsychotics may exacerbate obesity. So, a bidirectional relationship may exist between severe psychiatric disorders and medical conditions. In other words, each condition makes the other worse.

Modifiable Risk Factors for Medical Comorbidities in the Mentally Ill

Although suicide in patients with schizophrenia or bipolar disorder receives much attention, CVD contributes to more deaths and more years of life lost than any other single factor (for example, see AV 1AV 1).2 Heart disease is already a major health problem in the general population, but the risks are further increased for individuals with serious mental disorders. Modifiable risk factors for CVD and other somatic conditions associated with schizophrenia and bipolar disorder include diabetes, hypertension, lipid abnormalities, physical inactivity, and smoking, among others.8 Psychotropic medications may play a role in contributing to certain modifiable risk factors such as overweight and obesity, which is a major contributor to the development of CVD. Efficacy across antipsychotic classes is generally similar, so focusing on a drug’s potential impact on body weight as part of an overall plan to manage risk factors for serious medical comorbidities may help to decrease rates of CVD and lower mortality rates for patients with schizophrenia and bipolar disorder.


Treatment Recommendations for Managing the Risks Associated With Antipsychotic Treatment

Some of the pharmaceutical agents that are most effective in the treatment of severe mental illnesses are also associated with increased body weight and obesity and a host of related medical complications. The use of medications that may promote weight gain is not entirely avoidable. However, for some patients, pharmacologic approaches that may be helpful include initially prescribing or switching to antipsychotics that are weight neutral or promote weight loss (AV 2AV 2).9 Depending on the patient and the disorder, combining a weight-loss promoting agent with the primary antipsychotic may also be effective. Behavioral weight management approaches for patients being treated with antipsychotics may also be used to control weight gain in some patients.

Drug Names

aripiprazole (Abilify), olanzapine (Zyprexa), risperidone (Risperdal and others), ziprasidone (Geodon)

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