After searching 12 years for bipolar disorder's cause, U-M team concludes it has many

December 15, 2017

ANN ARBOR, Mich. - Nearly 6 million Americans have bipolar disorder, and most have probably wondered why. After more than a decade of studying over 1,100 of them in-depth, a University of Michigan team has an answer - or rather, seven answers.

In fact, they say, no one genetic change, or chemical imbalance, or life event, lies at the heart of every case of the mental health condition once known as manic depression.

Rather, every patient's experience with bipolar disorder varies from that of others with the condition. But all of their experiences include features that fall into seven classes of phenotypes, or characteristics that can be observed, the team reports in a new paper in the International Journal of Epidemiology.

The team, from U-M's Heinz C. Prechter Bipolar Research Program, collected and analyzed tens of thousands of data points over years about the genetics, emotions, life experiences, medical histories, motivations, diets, temperaments, sleep patterns and thought patterns of research volunteers. More than 730 had bipolar disorder, and 277 didn't. Three-quarters of them are currently active research participants in the Longitudinal Study of Bipolar Disorder..

Using those findings, the team has developed a framework that could be useful to researchers studying the condition, clinical teams treating it, and patients experiencing it. The team hopes it will give them all a common structure to use during studies, treatment decisions and more.

"There are many routes to this disease, and many routes through it," says Melvin McInnis, M.D., lead author of the new paper and head of the program based at the U-M Depression Center. "We have found that there are many biological mechanisms which drive the disease, and many interactive external influences on it. All of these elements combine to affect the disease as patients experience it."

The Prechter program, funded by gifts from many donors, is named for a late Detroit automotive pioneer who fought bipolar even as he built a successful business.

Long-term funding from this program has made it possible to build a massive library of data from the "Prechter cohort" of patients, which is two-thirds female, and 79 percent white, with an average age at enrollment in the study of 38 years. On average, participants had had their first depressive or manic episode when they were 17, and many had other mental health conditions.

Seven classes and the key findings that shaped them

The seven phenoclasses, as the U-M team has dubbed them, include standard measures doctors already use to diagnose and track the progress of bipolar disorder.

In addition, they include:Some of the key findings made in the Prechter cohort by the U-M team include:Even though bipolar disorder tends to run in families, the long-term study has revealed no one gene that 'carries the day' to explain it, says McInnis, who is the Woodworth Professor of Bipolar Disorder and Depression in the U-M Medical School's Department of Psychiatry.

"If there was a gene with a strong effect like what we see in breast cancer, for instance, we would have found it," he explains. "We hope this new framework will provide a new approach to understand this disorder, and other complex diseases, by developing models that can guide a management strategy for clinicians and patients, and give researchers consistent variables to measure and assess."

He adds, "Bipolar disorder has a lot to teach humankind about other illnesses, because it covers the breadths of human mood, emotion and behavior like no other condition. What we can learn in bipolar about all these factors will be directly applicable to monitoring other disorders, and personalizing the approach to managing them."
-end-
The Prechter Bipolar Research Program is still recruiting participants for its long-term study, and accepting donations from those who want to help the research move forward. More information is available at http://www.prechterprogram.org.

Michigan Medicine - University of Michigan

Related Bipolar Disorder Articles from Brightsurf:

Amygdala changes in male patients with schizophrenia and bipolar disorder
Researchers in Japan have revealed that DNA methylation occurs in the serotonin transporter gene that regulates neurotransmitter transmission in schizophrenia and bipolar patients.

Effect of high-deductible insurance use in bipolar disorder
A new study led by the Department of Population Medicine finds that individuals with bipolar disorder who switched to high-deductible health plans (HDHPs) experienced a moderate decrease in nonpsychiatrist mental health outpatient visits, but rates of psychiatrist visits, medication use, emergency department visits, and hospitalizations did not change.

Is bipolar disorder associated with increased risk of Parkinson's disease?
This study, called a systematic review and meta-analysis, combined the results of seven studies with 4.3 million participants to examine a potential association between bipolar disorder with a later diagnosis of Parkinson's disease of unknown cause.

Bipolar disorder may be linked to Parkinson's disease
People who have bipolar disorder may be more likely to later develop Parkinson's disease than people who do not have bipolar disorder, according at a study published in the May 22, 2019, online issue of Neurology®, the medical journal of the American Academy of Neurology.

Probiotics could help millions of patients suffering from bipolar disorder
About 3 million people in the US are diagnosed every year with bipolar disorder, a psychiatric condition characterized by dramatic shifts in mood from depression to mania.

Novel intervention for anxiety symptoms among people with Bipolar Disorder
Psychologists at Lancaster University have devised a novel psychological intervention to address Anxiety in Bipolar Disorder (AIBD).

Mutation links bipolar disorder to mitochondrial disease
Mutations in the gene ANT1 may confer a risk for bipolar disorder through a complex interplay between serotonin and mitochondrial signaling in the brain.

A new path into bipolar disorder comes to light
A new article authored by an international group of researchers reveals a novel potential drug target for bipolar disorder and offers new insights into the underlying biology of this lifelong and devastating mental illness.

After searching 12 years for bipolar disorder's cause, U-M team concludes it has many
Nearly 6 million Americans have bipolar disorder, and most have probably wondered why.

Simple EKG can determine whether patient has depression or bipolar disorder
A groundbreaking Loyola Medicine study suggests that a simple 15-minute electrocardiogram could help a physician determine whether a patient has major depression or bipolar disorder.

Read More: Bipolar Disorder News and Bipolar Disorder Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.