While manic and depressive states are well-known symptoms of bipolar disorder, often overlooked heart problems also put this patient population at great risk. Benjamin Goldstein, M.D., Ph.D., a professor of psychiatry and pharmacology at the University of Toronto, hopes to change all that.
For over a decade, Goldstein has been conducting research to understand why bipolar disorder and heart problems seem so closely connected, as well as raising public awareness about this connection. His goal is to reframe bipolar disorder as not only a psychiatric illness, but also a cardiovascular one.
Interest in Childhood Bipolar Reveals Early Emergence of Heart Problems
Goldstein became interested in the connection between bipolar disorder and heart problems about 12 years ago, after starting a postresidency training in child and adolescent mood disorders at the University of Pittsburgh with Boris Birmaher, M.D.
At that time, the diagnosis of bipolar disorder in children was an area of vigorous debate. Many psychiatrists questioned the existence of bipolar disorder before adolescence, believing that children diagnosed with early-onset bipolar disorder had some other conduct or behavioral disorder common in children.
David Kupfer, M.D., who was then chair of psychiatry at the University of Pittsburgh and also a mentor to Goldstein, was one of the first psychiatrists to advocate for a better appreciation of the physical health problems facing adults with bipolar disorder. Goldstein figured that if children diagnosed with early-onset bipolar disorder had similar types of medical problems as adults with bipolar, then that would support the validity of a bipolar diagnosis. He decided to examine weight in the children with bipolar disorder and found that about 40 percent of the youth were overweight or obese. What’s more, obesity correlated with worse psychiatric symptoms in these pediatric patients. Both findings were similar to what had been seen in adults.
Goldstein began studying the frequency and age of onset of heart disease among adults with bipolar disorder in large epidemiologic studies. His research led him to the discovery that people with bipolar disorder are about three times more likely to develop heart disease than the general population. Adults with bipolar disorder developed heart disease in their mid-40s—about 17 years younger than people in the general population and 10 years younger than adults with major depressive disorder, a group also known to be at risk of cardiovascular problems.
Some studies have suggested that manic symptoms create additional cardiovascular stress. Others have suggested that the higher risk of cardiovascular problems is the result of bipolar depression being generally severe and difficult to treat. Goldstein believes that it is the overall burden of depressive and manic symptoms that creates this greater risk of heart disease.
Cardiovascular Deficits Start Early
Goldstein said that while it is possible that medication side effects, limited physical activity, and/or smoking by patients with bipolar disorder may heighten the risk of cardiovascular problems, “there are biological connections above and beyond these explanations.” He pointed out that some of his research has shown that even in teens recently diagnosed with bipolar disorder, cardiovascular deficits are already evident.
One example of the differences seen in youth with bipolar disorder is in cerebrovascular reactivity—or how well the many tiny blood vessels in the brain dilate and contract in response to biochemical signals. Using brain scans, Goldstein and colleagues have found that youth with bipolar disorder have less cerebrovascular reactivity than healthy teens. If these blood vessels do not respond to biochemical signals properly, the health of surrounding brain tissue can be impacted. This, in turn, may contribute to both the mood symptoms associated with bipolar disorder and to future risk of stroke, he said.
Goldstein has also shown that among youth with bipolar disorder, those with higher triglyceride levels have more problems with executive function, and youth with hypertension have higher levels of impulsivity. While Goldstein noted these are only associations between poor cardiovascular health and worse mood states, the findings point to a connection between the mind and the heart.
Promoting Heart Health Can Help Patients With Bipolar Disorder
Understanding the connections between bipolar disorder and heart problems may assist with early interventions, Goldstein said. He and other researchers have found that aerobic exercise—even just a single session—can temporarily normalize blood flow and improve brain function in youth with bipolar disorder.
“When physicians discuss the importance of heart health with young or middle-aged patients, they usually do so with an eye to the future—highlighting the lower risk of heart disease in 20 or 30 years,” Goldstein told Psychiatric News. “But for young people with bipolar disorder, being heart healthy can help the mind in the here and now.”
To help drive home the message that bipolar disorder impacts the cardiovascular system, Goldstein and several colleagues worked with the American Heart Association (AHA) in 2015 to put forth an official statement that bipolar and other mood disorders in young people are significant and independent risk factors for early atherosclerosis and heart disease. “That recognition by the AHA was rewarding as it added a lot of legitimacy to my team’s work,” Goldstein said.
“There is no question that Benjamin, who was terrific while at Pittsburgh, has continued to function at a high level in both academics and research,” said Kupfer of his former mentee. “Working with both adults and children, his work has established this important interface between bipolar disorder and cardiovascular disorders.
“Does every pediatrician or primary care doctor know about this interface? Probably not, and they should,” Kupfer continued. “It makes early intervention for either disorder that much more important.” ■