Bipolar disorder is a mental health condition defined by episodes of depression and mania. ¹ While scientists don’t 100% understand what causes bipolar disorder, we have a better comprehension thanks to recent research. Throughout this article, we’ll take a deeper look at bipolar disorder’s causes.

Bipolar’s Relationship with the Brain

Doctors have linked bipolar disorder to underlying problems in the brain. More specifically, to the neurotransmitters: ²

• Dopamine – A chemical released that makes your brain and body feel good.

• Norepinephrine (noradrenaline) – Increases heart rate, blood pumping (from the heart), blood pressure, blood sugar levels, energy, and helps to break down fat.

• Serotonin – Stabilizes mood and sense of well-being.

Irregular levels of norepinephrine and serotonin have been linked to several mental disorders, such as depression. However, in disorders associated with psychosis (i.e. schizophrenia), dopamine regulation is disrupted.

While researchers understand that these irregularities can cause mood disorders, researchers still aren’t 100% sure how these irregularities begin.

Is Bipolar Disorder Genetic?

Many studies link bipolar disorder to genetics. In other words, if a close family member (i.e. parent or sibling) struggles with bipolar disorder, you’re more likely to develop the condition. ³

The most convincing evidence comes from twin studies. Scientists have reported that if one identical twin is diagnosed with bipolar disorder, there’s a 40% to 70% chance the other twin will also have a diagnosis. ⁴

Research also indicates bipolar II is much more prevalent in concerns with genetics than bipolar I. ⁵

However, not everyone with a genetic history of bipolar will develop the condition. There is a chance you can develop another psychiatric illness (i.e. anxiety, depression, or attention-deficit/hyperactivity disorder) due to a close relative having bipolar disorder. ⁶

Is Bipolar Disorder Environmental?

Beyond the genetic link, bipolar disorder is also related to one’s environment, especially, during childhood. If a parent struggles with the condition, they’ll likely surround their child with many environmental stressors, including: ⁷

• Alcohol or substance abuse
• Financial and sexual indiscretions
• Hospitalizations
• Mood swings

Furthermore, bipolar parents may make their children susceptible to other psychiatric conditions due to bipolar behaviors. For example, if a bipolar parent causes physical or verbal abuse, their child may be susceptible to conditions like post-traumatic stress disorder (PTSD). ⁸

Environmental stressors are only a concern when a person is genetically predisposed to bipolar disorder. However, they may still be at risk of other mental conditions.

What Causes Bipolar Disorder Symptoms to Worsen?

Certain lifestyle habits may worsen bipolar disorder. These include:

• Arguments with Loved Ones – Even if an argument isn’t directly about your bipolar symptoms, it can lead to both manic or depressive episodes.

• Irregular Sleep – Changes in sleep patterns or irregular sleep (i.e. too much or too little) can harm your mood. ⁹

• Life Stresses – Whether it’s a breakup, financial difficulty, or a traumatic event, life stressors are related to worsened moods. ¹⁰

• Substance Abuse – If you use alcohol or drugs to self-medicate, chances are they’ll only worsen your bipolar disorder. ¹¹

While treatment is essential in overcoming bipolar disorder, it can also help to make certain lifestyle changes.

Final Word

More research is necessary to better understand what causes bipolar disorder. While scientists have a good idea of who’s susceptible, there’s no clear indication of risk factors until symptoms are apparent.

If you begin to notice bipolar symptoms, it’s important to seek out medical help as soon as possible. The sooner bipolar disorder is addressed, the better chance someone has at overcoming symptoms.

References

¹ Jain A, Mitra P. Bipolar Disorder. 2023 Feb 20. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan–. PMID: 32644424.

² Manji HK, Quiroz JA, Payne JL, Singh J, Lopes BP, Viegas JS, Zarate CA. The underlying neurobiology of bipolar disorder. World Psychiatry. 2003 Oct;2(3):136-46. PMID: 16946919; PMCID: PMC1525098.

³ Kerner B. Genetics of bipolar disorder. Appl Clin Genet. 2014 Feb 12;7:33-42. doi: 10.2147/TACG.S39297. PMID: 24683306; PMCID: PMC3966627.

⁴ Squarcina L, Fagnani C, Bellani M, Altamura CA, Brambilla P. Twin studies for the investigation of the relationships between genetic factors and brain abnormalities in bipolar disorder. Epidemiol Psychiatr Sci. 2016 Dec;25(6):515-520. doi: 10.1017/S2045796016000615. Epub 2016 Sep 19. PMID: 27641241; PMCID: PMC7137663.

⁵ Kerner B. Toward a Deeper Understanding of the Genetics of Bipolar Disorder. Front Psychiatry. 2015 Aug 3;6:105. doi: 10.3389/fpsyt.2015.00105. PMID: 26283973; PMCID: PMC4522874.

⁶ Andreassen OA, Hindley GFL, Frei O, Smeland OB. New insights from the last decade of research in psychiatric genetics: discoveries, challenges and clinical implications. World Psychiatry. 2023 Feb;22(1):4-24. doi: 10.1002/wps.21034. PMID: 36640404; PMCID: PMC9840515.

⁷ Aldinger F, Schulze TG. Environmental factors, life events, and trauma in the course of bipolar disorder. Psychiatry Clin Neurosci. 2017 Jan;71(1):6-17. doi: 10.1111/pcn.12433. Epub 2016 Sep 21. PMID: 27500795; PMCID: PMC7167807.

⁸ Springer KW, Sheridan J, Kuo D, Carnes M. The long-term health outcomes of childhood abuse. An overview and a call to action. J Gen Intern Med. 2003 Oct;18(10):864-70. doi: 10.1046/j.1525-1497.2003.20918.x. PMID: 14521650; PMCID: PMC1494926.

⁹ Gold AK, Sylvia LG. The role of sleep in bipolar disorder. Nat Sci Sleep. 2016 Jun 29;8:207-14. doi: 10.2147/NSS.S85754. PMID: 27418862; PMCID: PMC4935164.

¹⁰ Koenders MA, Giltay EJ, Spijker AT, Hoencamp E, Spinhoven P, Elzinga BM. Stressful life events in bipolar I and II disorder: cause or consequence of mood symptoms? J Affect Disord. 2014 Jun;161:55-64. doi: 10.1016/j.jad.2014.02.036. Epub 2014 Mar 18. PMID: 24751308.

¹¹ Cerullo MA, Strakowski SM. The prevalence and significance of substance use disorders in bipolar type I and II disorder. Subst Abuse Treat Prev Policy. 2007 Oct 1;2:29. doi: 10.1186/1747-597X-2-29. PMID: 17908301; PMCID: PMC2094705.