Bipolar disorders appear to increase the risk of early death from a medical illness, according to a literature review study published as the lead article this week in the journal Psychiatric Services.
The researchers comprehensively reviewed 17 studies involving more than 331,000 patients. Evidence suggested that people with bipolar disorder have a higher mortality from natural causes compared to people in the general population of similar age and gender but without mental illness. The various studies indicated that the risk was from 35 percent to 200 percent higher. The risk is the same for men and women. The most common conditions leading to premature death were heart disease, respiratory diseases, stroke, and endocrine problems such as diabetes.
"The review of data gathered from large population studies suggests that having bipolar disorder is similar to being a smoker in terms of increasing a person's risk of early death," said Dr. Wayne Katon, a University of Washington (UW) professor of psychiatry. He co-authored the study with third-year UW psychiatry resident Babak Roshanaei-Moghaddam. The article is titled, "Premature Mortality from General Medical Illnesses Among Persons with Bipolar Disorder: A Review." Katon is a noted researcher on the interplay between life-shortening medical conditions and mood disorders.
People with bipolar disorder tend to have manic phases and depressed phases in their lives. During mania, they might be too wound up to sleep, their thoughts might race, and they might have boundless energy. During depression, they might feel painfully sad, hopeless, and immobilized.
In the past, the higher premature death rate among people with bipolar disorder was attributed to a higher rate of suicide and accidents. More recently, Katon said, researchers are finding that, while rates of suicides and accidents are indeed greater among those with bipolar disorder compared to the general population, they only partly account for the higher premature death rate. Emerging evidence, Katon said, shows that the majority of early deaths among people with bipolar disorder come from medical conditions.
As psychiatric conditions such as bipolar disorder become more treatable, Katon said, "We're saving people from this illness and losing them to other medical illnesses."
The possible reasons for this higher risk of premature death are manifold. Many factors could be contributing to poor physical health among people with bipolar disorder, according to the published report. These include unhealthy diet, binge eating, lack of exercise, smoking, substance abuse, social deprivation, living alone, homelessness, lack of access to health services, biased attitudes of health professionals towards people with psychiatric illnesses, failure among psychiatrists to address their patient's medical problems, or delaying medical care because of the overriding need for psychiatric treatment.
Biological abnormalities associated with bipolar illness might also be shortening lives, Katon noted. The illness can stress the immune system and the hypothalamic-pituitary axis, a system that controls many body processes. Bipolar disorders also heighten the activity of the sympathetic nervous system, which sets off the fight-or-flight response to stress.