Many Bipolar Patients Face Multiple Medical Illnesses

A 70-year-old woman we'll call “Rose” has bipolar disorder, but she has also experienced a plethora of medical problems within the past few months—a growth under her tongue, the need for a cardiac pacemaker, a small stroke, and blood poisoning that almost killed her.

Yet even bipolar patients who are much younger than Rose are apt to suffer from a spate of medical illnesses, a new study has found.

It was conducted by Caroline Carney, M.D., an associate professor of internal medicine and psychiatry at Indiana University, and Laura Jones, a research fellow with Medical Informatics in Indianapolis. Results were published in the September/October Psychosomatic Medicine.

Carney and Jones used all of the inpatient and outpatient claims submitted by health care professionals to Wellmark Blue cross/Blue Shield of Iowa from 1996 through 2001 for their study. They identified 3,557 individuals for whom claims had been submitted and who had a diagnosis of bipolar disorder with or without other psychiatric conditions except for schizophrenia or schizoaffective disorder. In addition 726,262 individuals for whom health insurance claims had been submitted, but who had no documented claims for psychiatric conditions served as controls.

Carney and Jones then looked for differences between bipolar subjects and control subjects concerning 44 chronic medical illnesses. They assessed possible confounding factors such as age, gender, place of residence, and number of health care visits for nonpsychiatric conditions.

Many Had Multiple Illnesses

The bipolar subjects were found to have significantly more medical comorbidity than did controls. Most notably, 41 percent of bipolar subjects had three or more chronic medical conditions, compared with only 12 percent of control subjects—a highly significant difference.

Moreover, the bipolar subjects' greater susceptibility to medical illness was found to span nearly every organ system in the body. For instance, compared with controls and taking possibly confounding factors into consideration, bipolar subjects were three times as likely to have abused nicotine, have asthma, and have experienced a stroke; four times as likely to have experienced liver disease; 10 times as likely to have HIV infection or AIDS; 20 times as likely to have abused alcohol; and 43 times as likely to have abused multiple substances.

“I was really surprised by the breadth of the differences between the controls and cases,” Carney told Psychiatric News.

In fact, hyperlipidemia, lymphoma, and metastatic cancer were the only medical conditions out of the 44 examined that were less likely to occur in the bipolar group than in the controls.

Regarding the cancer findings, Carney said she would like to think that there might be something in bipolar disorder that protects against cancer. Indeed, the findings mesh with those of a Swedish study that found that individuals with bipolar disorder have higher rates of death from all natural causes except cancer. What is more likely, she fears, is that bipolar patients might be dying earlier of other conditions before malignancies are detected.

But perhaps the most disturbing discovery was that the average age of the bipolar subjects was only 39, indicating that bipolar patients are often afflicted with serious medical difficulties even at a young age.

Hypotheses Suggested

The reasons why bipolar persons are susceptible to so many medical problems is yet to be determined. However, Carney and Jones offered some possible explanations in their study.

For example, nicotine abuse, which was three times as prevalent in the bipolar subjects, might partially explain the bipolar group's threefold greater risk of asthma and stroke. Their markedly heightened odds of abusing alcohol may explain why conditions related to alcohol use, such as peptic ulcer disease, liver disease, and pancreatitis, were more common in them than in controls. Lithium treatment for bipolar illness might be responsible for the hypothyroidism and kidney failure from which the bipolar group suffered significantly more often than did the controls.

All in all, Carney said, “This study strongly calls for the integration of medical and psychiatric services. As practice currently stands, mental health and medical services are generally delivered in different venues at different times. Communication between providers is often problematic. Systems of care designed to ensure integrated delivery may improve the recognition of medical conditions, preventive interventions, and overall access to care for persons with chronic mental illness.”

In the opinion of Carol Alter, M.D., an associate professor of psychiatry at Georgetown University and a member of the APA Council on Psychosomatic Medicine, the results of this study constitute “important information—as stated by the authors, there really has been no population-based look at the relationship of medical comorbidities to bipolar illness. Even with the limitations of the design—such as using subjects only from Iowa, one of the least-diverse states in the country, and not controlling for levels of nicotine use—the high rates of medical illness are impressive, [as is] the young age [at which they occur]. The data are not unlike the data we see with schizophrenia and speak to the chronicity and functional detriments associated with mental illness. One would likely guess that if they had access to data from public systems that the number of medical problems would be even greater.”

An abstract of “Medical Comorbidity in Women and Men With Bipolar Disorders: A Population-Based Controlled Study” is posted at<www.psychosomaticmedicine.org/cgi/content/abstract/68/5/684>.▪