Alexander Marshall discusses the underlying causes of bipolar disorder, how individuals can be affected, and where those in need can find help
Bipolar disorder is still one of the most misunderstood mental health issues in our society, despite the consequences of the condition being far too serious to ignore. 10% of patients will commit suicide, and half will deal with some form of substance abuse. The biology behind mental health conditions is generally poorly understood due to their complexity.
Bipolar disorder is a mood disorder which sees patients swing from the deepest depths of despair to the highest peaks of mania. While the symptoms of depression (which include overeating, a lack of energy and interest, difficulty thinking, hopelessness and suicidal thoughts) are much more widely known, many people would not recognise the symptoms of manic behaviour.
Contrary to depression, manic behaviour is an extended sense of euphoria and energy, and while that may sound somewhat pleasant, it results in irritability, increased sexual desire and risk-taking, insomnia, delusions and hallucinations. Due to these symptoms, those affected can find it difficult to maintain relationships, accumulate debt, and even fail to prioritise their own safety, as a sense of being unrestrained by normal limits overwhelms them.
The length of these mood cycles can vary, and in some cases even overlap, posing a severe threat as the individual suffers from both high energy levels and suicidal thoughts. The unpredictability of these cycles, as well as nuances in the condition (such as bipolar disorder type II, which does not manifest in full manic episodes, but instead has more frequent ‘hypomanic’ moods that lack delusions and hallucinations), makes diagnosis difficult. Often, bipolar disorder will not be diagnosed until 5-10 years after onset, and initial prescriptions for depression can even cause severe mania as a side effect, complicating the situation.
While the exact cause remains a mystery, genetic studies have started providing clues. The condition has a strong genetic basis, with direct relatives of patients being 10 times more likely to also suffer from the disorder. In particular, many of these studies identify a link to genes involved in calcium regulation. Although calcium is more widely associated with the growth of healthy teeth and bones, in trace amounts it actually plays a vital role in controlling many processes including cell death, how cells communicate with one another, and how cells utilise food sources.
The brain is one of the most energy-intensive organs in the body. However, the brain cells of bipolar patients appear to have reduced reservoirs of energy to draw upon. Cells regulate their energy production through their mitochondria, otherwise known as the ‘powerhouses’ of the cell. In bipolar patients, these mitochondria appear smaller and misshapen, and specific areas of the brain accumulate lactic acid. Most people will be familiar with lactic acid build up as the painful stitch after exerting themselves with exercise; however, the increased levels in the brain are a significant indicator that the supply of nutrients and energy to the brain cells is disturbed.
The most common type of treatment is currently lithium, which, while successful at repressing bipolar episodes, produces several unpleasant side effects including vomiting and tremors. Now, however, treatments which have previously been used for epilepsy are currently being investigated for use with bipolar disorder, and aim to be more effective with fewer adverse effects. Specifically, these drugs are thought to target calcium regulation and are showing promise in early trials.
Whilst the dysregulation of calcium may be a major factor causing bipolar disorder, it’s probably too early to be burning down the dairy farms. In particular, calcium is vital for the normal function of the brain, so any potential treatment will have to delicately alter its minute levels. Calcium is by no means the only candidate which could be playing a role though, as scientists also look into the contributing effect of our own internal clock, and how our brains signal through the hormone dopamine.
In the end, as with all mental health conditions, the underlying biology is highly complex. However, the full picture is slowly coming into focus, and there is great reason to be optimistic for the effectiveness of future treatments.
If you are struggling with suicidal thoughts, please seek help from a professional and contact the UK Samaritans. The UK Samaritans operates a 24 hour service available every day of the year (their phone number is 116 123). Instead, if you prefer to write down how you’re feeling, or if you’re worried about being overheard on the phone, you can email Samaritans at firstname.lastname@example.org.
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