Two new studies explore different aspects of medical illness in people with schizophrenia. In one study, conducted in Iowa, researchers collected medical claims from Blue Cross Blue Shield records for more than 1,000 people with schizophrenia and more than 700,000 people without the condition over a six-year period. Adjusting for age, those with schizophrenia (average age, 40) had a higher rate of chronic illnesses affecting almost every system in the body.
People with schizophrenia were nearly three times as likely to be smokers and have low thyroid function, and had nearly eight times the rate of the infectious disease hepatitis C. They were about twice as likely to have disorders such as asthma, stroke, peripheral vascular disease, chronic obstructive pulmonary disease, and diabetes. Their rate of coronary artery disease and high blood pressure was only slightly higher than average, possibly because they are correctly diagnosed for these commonly symptomless disorders even less often than most people.
Physical illness becomes chronic in schizophrenia sufferers partly because they don't get the treatment they need. They may not seek treatment, and mental health professionals are not always keeping track of their patients' physical condition. The resulting ill health raises the risk of prolonged hospitalization, suicide, accidents, and drug overdoses. Some disorders, such as hypothyroidism, can exacerbate psychiatric symptoms.
The second study, from Singapore, involved a different class of people with schizophrenia—those undergoing a first episode of psychosis. The 142 subjects were admitted to psychiatric hospitals after a psychotic episode. All were re-examined after six months, a year, and two years. Those whose psychosis resulted from a medical illness were excluded. The surprising finding: At least in the first couple of years, people with physical symptoms had a better than average outcome.
The participants in this study were mostly young—the average age was under 30—so they rarely had chronic physical illness. Even so, their rate of diabetes and high blood pressure was much higher than average for their age. More than 20% had some physical symptoms, mainly cardiovascular and respiratory. Compared to those without physical symptoms, they seemed to understand the consequences of their mental illness better. At the follow-ups, on average, they were more conscious of the need for treatment, their psychiatric symptoms had improved more, and their physical health had declined less. Maybe they were more familiar with health services and more accustomed to taking medications and it's possible that the physical symptoms gave them more incentive to accept and comply with any kind of treatment.
Like the Iowa study, the Singapore study confirmed that people with serious mental illness need to be more effectively monitored for and educated about physical symptoms, for the sake of their minds as well as their bodies.
Carney C, et al. "Medical Comorbidity in Women and Men with Schizophrenia: A Population-Based Controlled Study," Journal of General Internal Medicine (November 2006): Vol. 21, No. 11, pp. 1133–37.
Sim K, et al. "Physical Comorbidity, Insight, Quality of Life and Global Functioning in First Episode Schizophrenia: A 24-Month, Longitudinal Outcome Study," Schizophrenia Research (December 2006): Vol. 88, Nos. 1–3, pp. 82–89.