According to the National Alliance on Mental Illness, bipolar disorder is a “mental illness that causes dramatic shifts in a person’s mood, energy and ability to think clearly.” The disorder is characterized by periods of elevated mood and high energy alternating with periods of low mood and motivation (depression.) The exact causes of bipolar disorder, however, have remained elusive to researchers.
There are a few different types of bipolar disorder, but the most common are Bipolar Type 1, which is characterized by increased mania, and Bipolar Type 2, which is characterized by intense depressive episodes as well as hypomania (a mild form of mania.) Each episode could last anywhere from days to months.
All types of bipolar disorder can be severe and may increase the risk of suicide. The National Institute of Mental Health reports that 2.6% of adult Americans (nearly 6 million people) are diagnosed with bipolar disorder. Of these cases, 83% are considered severe.
About The Study
Following a 12-year-long study, researchers at the University of Michigan say they have uncovered seven different causes of bipolar disorder, a troubling mental health condition that has traditionally been underdiagnosed, misdiagnosed, and poorly understood.
For the study, researchers examined 1,100 people, which included 730 who were diagnosed with bipolar disorder and 277 who were not. More than three-quarters were active research subjects in the Longitudinal Study of Bipolar Disorder, and on average, participants experienced their first bipolar episode when they were 17. They also tended to suffer from co-occurring mental health conditions.
Lead author Melvin McInnis, M.D., as quoted in a press release:
“There are many routes to this disease, and many routes through it. 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.”
Dr. McInnis and other researchers examined data on genetics, medical history, diet and sleep habits, emotions, life experiences, and certain thoughts and behavior patterns. They pinpointed seven “Phenotypic classes” or potential causes of bipolar disorder.
- Disease – genetic risk factors/predisposition puts some people at a greater risk of developing bipolar disorder
- Neurocognitive – thought and emotion patterns
- Temperament Personality – personality traits, behaviors, and activity
- Motivated Behaviors – activities such as substance use and substance use disorder
- Life Story – past experiences, aspects of family and intimate relationships and possible emotional traumas
- Sleep and Circadian – the influence of sleep on the disorder
- Outcomes and Course – the change or improvement of bipolar symptoms over time and with medical treatment.
In addition to these potential causes of bipolar disorder, the researchers also identified several factors and trends associated with sufferers. These include:
- Those with bipolar disorder were more likely to also suffer from eating disorders, anxiety disorder, and substance abuse.
- They were also three-and-a-half time more likely to suffer from chronic migraines.
- Many of the participants studied experienced childhood trauma, more so that those who did not have bipolar disorder.
- Female participants in the study tended to experience greater severity of symptoms when they were sleeping poorly. Sleeping habits did not appear to affect men, however.
- It was also found that two genes may make someone more vulnerable to developing bipolar disorder, but researchers also noted that many genetic variations had been associated with the disorder.
- Study participants also had consumed higher levels of saturated fats, and certain types of fats were associated with the severity of the mood swings.
- They found differences at the cellular level between bipolar and non-bipolar patients – neurons derived from stem cells of those with bipolar disorder were shown to be more excitable in comparison to other individuals.
Finally, they determined that cognitive abilities such as memory and motor skills were poorer in study subjects who had bipolar disorder.
Traditionally-Recognized Risk Factors
According to the Mayo Clinic, factors that may increase the risk of developing bipolar disorder or serve as a catalyst for the first episode include:
- Having a first-degree relative with bipolar disorder, such as a parent
- Periods of high distress, such as the death of a loved one or another traumatic event
- Drug or alcohol misuse
Treatment for Bipolar Disorder
The International Bipolar Foundation recommends a comprehensive treatment plan which includes medication, psychotherapy, education, peer support, and management of lifestyle risk factors. And the complex nature of this disorder requires an individualized treatment program versus a one-size-fits-all approach.
“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.”
“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.”
~ G. Nathalee Serrels, M.A., Psychology