Family history of bipolar disorder: what it means for risk

The NHS describes bipolar disorder as a mental health condition where you have extreme mood changes. You sometimes have high moods, called mania or hypomania, and sometimes low moods, which are depression. These moods usually last a few days or weeks at a time, and between episodes many people have long periods of stable mood lasting weeks, months or years.

It is different from ordinary mood variation, and it can take time to diagnose because it affects everyone differently and symptoms are similar to other mental health conditions.

The NHS says it is not known exactly what causes bipolar disorder, but that you are more likely to have it if you have a parent, brother or sister who has bipolar disorder. NHS inform likewise says genetics are involved and that it can run in families.

The sources do not give the size of the added risk, and they do not say that a family history means you will develop it. Plenty of people with an affected relative never have the condition, and plenty of people with bipolar disorder have no affected relative.

Psychiatrists ask about family history as part of an assessment: NHS inform says the specialist will ask about your symptoms, when you first experienced them, how you have felt recently, your medical background and your family history.

The NHS says there are some things that can increase your chances of having bipolar disorder, in addition to a family link. NHS inform adds chemical imbalances in the brain to the list of possible factors.

• Childhood trauma or abuse.

• A stressful event such as relationship problems, abuse, the death of someone close or money problems.

• Recreational drugs such as cannabis or cocaine.

• A parasite called toxoplasma gondii, which causes toxoplasmosis.

The NHS says high mood symptoms can include feeling very happy and excited, being very irritable or aggressive, having a lot of energy and not needing much sleep, racing thoughts, speaking fast, a high sex drive, being overly confident, being impulsive or extravagant such as spending lots of money, and sometimes hallucinations, delusions or paranoia.

Low mood symptoms can include feeling sad, losing interest in things, low energy, difficulty sleeping or sleeping a lot, eating too much or too little, low confidence, feeling worthless or hopeless, difficulty concentrating, avoiding people, and having suicidal thoughts or thoughts about harming yourself.

NHS inform describes rapid cycling, with repeated swings from high to low without a normal period in between, and mixed states, in which symptoms of depression and mania occur together.

The NHS says if a GP thinks you may have bipolar disorder they will refer you to a mental health specialist, a psychiatrist. A treatment plan can include medicines to help stabilise your moods and talking therapy such as CBT. Some medicines are taken all the time and others only when symptoms get worse, and they can cause side effects.

The NHS says some medicines for bipolar disorder are not safe to take in pregnancy and advises talking to your doctor if you are pregnant or planning a pregnancy. If doctors are worried you are at risk of self-harm, suicide or harming someone else, you may need to stay in hospital or have support from a crisis team at home.

The NHS suggests you try to have a regular routine, get plenty of sleep, eat a healthy diet and exercise, manage stress, and avoid recreational drugs, smoking, too much alcohol, shift work, flying at night or across time zones, and lots of caffeinated drinks.

See a GP if you have extreme changes in your moods that last a long time or affect everyday life, or if you have been diagnosed and treatments are not helping. If you are worried about someone else, encourage them to speak to their GP.

The NHS says support is available if you or someone you know is having a mental health crisis or emergency. Call 999 or go to A&E in an emergency, and use NHS 111 for urgent advice.