Causes of bipolar disorder

Reading time: 3 min

The cause is in its origin, essentially, biological and genetic. The limbic system is responsible for regulating the emotions and that the mood is stable and in keeping with the circumstances. That is to say, it has a bearing in that each day we get up with a similar and coherent mood with what happens in life. Obviously, this mood will be more or less stable depending on different aspects, like physical health, rest, daily events, etc.

In the case of individuals that have a bipolar disorder, the limbic system functions erroneously, causing their mood to suffer sudden changes without there necessarily being a personal, work, family, or social reason, that justifies it. 

Neurotransmitters like dopamine, serotonin, and acetylcholine, play a crucial role in each phase. In the manic phases, there is an increase in dopamine levels, and in the depressive ones, a decrease in serotonin. Hormones, such as thyroxin, are also important.

El primer factor de riesgo –y la causa de la mayoría de recaídas- es dejar de tomar la medicación.

Pill with warning sign

The main risk factor—and the cause of the majority of relapses—is to stop taking the medication. Almost half of those that suffer from a bipolar disorder do not take the medication prescribed by their psychiatrist correctly, which may lead to the appearance of new episodes and a gradual worsening of the course of the illness.

Cannabis, pills and syringe crossed out

Another very common trigger is the consumption of alcohol and other toxic habits—cannabis, cocaine, designer drugs, and coffee abuse.

Woman getting out of bed with unrefreshing sleep

To sleep less than seven or eight hours, as this could be an indicator of the onset of euphoria phase, and may trigger an episode.

Pills with green and white stripes

Certain drugs that are used for other illnesses can also act as triggers for new episodes. Among them are the corticosteroids. In this sense, it is recommended to consult the psychiatrist if certain drugs can be taken.

Woman giving birth on a stretcher

Childbirth in some women can act as a trigger due to the hormonal changes. One usually hears of post-partum depression: this has nothing to do with psychological factors of the type “fear of the responsibility of being a mother” or “to feel empty”. It is simply a sudden drop in the level of oestrogens, which can lead to a post-partum depression episode—more common in women with a bipolar disorder—as well as post-partum mania.

Episode triggering factors

Psychological factors also have an important role as triggering factors, that is to say, they act as the trigger that sets off an episode. Psychological-type factors, such as stress or negative life events, can trigger a manic or depressive episode in an individual vulnerable to the disorder. 

Both negative and positive life events can trigger an episode. That is to say, an episode may start after being sacked from work, or after being promoted, after being divorced, or after starting a relationship. It is interesting that the positive or negative sign of the triggering event does not determine whether the episode is depressive or manic.

It is expected, for example, that someone with a bipolar disorder begins a depressive episode after the death of a loved one, but the reality is that many patients with a bipolar disorder start a manic episode after a distressing event. This leads to thinking to what extent the biological factors, more than the psychological ones, are decisive in this illness.

Apart from the psychosocial triggering factors, there are various situations that can lead to the appearance of a new episode.

Substantiated information by:

Ana Isabel Martínez Arán
Diego Alberto Hidalgo Mazzei
Eduard Vieta Pascual
Mercè Comes Forastero

Published: 20 March 2018
Updated: 20 March 2018

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