Schizophrenia is associated with increased medical comorbidity likely caused by interactions between life-style, environment, and the disease itself. High rates of medical comorbidity exist among all forms of serious mental illness. Affective disorders such as bipolar disorder and unipolar depression are associated with 1.5–2 times the mortality rate observed in the general population, and high rates of HIV and hepatitis A, B, and C exist among patients with severe mental illness. However, schizophrenia is particularly affected by medical comorbidities, and is associated with a 20% shorter-than-normal lifespan. This discussion focuses on rates of medical comorbidity in people with schizophrenia and the effects of medication on cardiometabolic risk factors. It is also important to recognize that lifestyle and environmental factors associated with serious mental illness, as well as poor access to healthcare, contribute to the elevated rates of medical illnesses observed in these populations as well.

Studies of the association between schizophrenia and medical comorbidities have suggested that the introduction of second-generation antipsychotics (SGAs) may be responsible for the increases observed in cardiovascular disease rates in this patient population, and that cardiovascular disease mortality may be shifting to an earlier stage of life. Ösby and colleagues observed that while overall cardiovascular mortality in schizophrenia patients in Sweden increased from 1976–1995, an even greater increase occurred in men from 1991–1995. This latter increase corresponded temporally to an increased use of SGAs.

Osborne and colleagues recently confirmed the observation made by Osby and colleagues. They compared 46,000 people with serious mental illness and a general population sample of ∼300,000 people from 1987–2002.