Depression with a long-term physical illness: causes and treatment in the UK

Depression that occurs alongside a physical illness is sometimes described as secondary depression or depression due to a medical condition. The link can run in several directions. The Royal College of Psychiatrists says physical health problems, particularly those that are serious or long-term, can cause depression or make it worse. NHS inform lists illness or a physical health problem among the things that can bring on depression, alongside bereavement, relationship problems, money worries and job loss.

Depression can also make a physical condition harder to manage. NICE notes that depression can affect how a person copes with treatment for a physical health problem, and lists that as one reason an antidepressant may sometimes be considered even for mild depression. For this reason NICE publishes specific guidance for adults who have depression and a chronic physical health problem.

There is no short list of illnesses that cause depression. The Royal College of Psychiatrists gives examples across several groups, and the list is not exhaustive.

• Life-threatening illnesses such as cancer and heart disease.

• Long-term or painful illnesses, such as arthritis.

• Viral infections such as flu or glandular fever, particularly in younger people.

• Hormonal problems, such as an under-active thyroid.

• Conditions affecting the brain or nervous system.

It can be difficult to tell what is the illness and what is depression, because tiredness, poor sleep, loss of appetite and low energy occur in both. The NHS says depression can cause persistent sadness lasting weeks or months, loss of interest in things you used to enjoy, feeling tearful, and physical symptoms such as feeling constantly tired, sleeping badly, having no appetite or sex drive, and various aches and pains.

Features that suggest depression rather than illness alone include hopelessness, loss of enjoyment that is out of proportion to the physical limits, and thoughts that life is not worth living. NHS inform adds feelings of guilt, irritability, low self-esteem and difficulty concentrating to the list. Many people with depression also have symptoms of anxiety, according to the NHS.

See a GP if you think you may be depressed. The NHS says many people wait a long time before seeking help, but it is best not to delay. The Royal College of Psychiatrists says your GP will review your symptoms, can carry out a physical check-up, and needs to know about any treatment for a physical illness you are already having so they can decide which antidepressant, if any, is most suitable.

If a medicine you take for another condition may be involved, do not stop it yourself. NICE says to contact your healthcare professional if you have concerns, and the same advice applies to any prescribed medicine.

NICE sets out the possible first treatments for mild to moderate depression in a person who also has a long-term physical health problem. These are a physical activity programme (a group exercise class that takes account of your physical ability and is coordinated with any rehabilitation), a peer support group of people with the same physical problem, a self-help programme with professional support, and computerised cognitive behavioural therapy. If none of these helps, NICE says you should be offered an antidepressant or psychological treatment such as CBT or behavioural couples therapy.

For mild depression NICE says an antidepressant is not usually offered but may help if depression persists after the first treatments, has lasted a long time, you have had moderate or severe depression before, or the depression is affecting the treatment of your physical problem. The NHS describes the overall picture: lifestyle changes, talking therapies and medicine, depending on severity, with specialist referral for severe depression.

NICE says a GP should offer advice on going to bed and getting up at regular times, not eating large meals or drinking alcohol just before bed, and taking regular exercise where possible, as these can improve sleep. NICE also says healthcare professionals should not offer or advise St John's wort, because the right dose is unclear, preparations vary, and it can cause serious problems with other medicines including the contraceptive pill, anticoagulants and anticonvulsants.

The NHS suggests that a support group or self-help book can help you better understand what causes you to feel depressed.

The NHS says severe depression can make you feel suicidal and that life is no longer worth living. If you have seriously harmed yourself or feel you may be about to, call 999 or go to A&E. If you need urgent advice, call NHS 111 and choose the mental health option.

Most people with depression are treated by their GP, as the Royal College of Psychiatrists says, with referral to psychological therapy services or a specialist mental health team if needed. Your hospital team for the physical condition may also be able to advise or refer you.

Some people also see a private psychiatrist or therapist for faster access. Whichever route you use, make sure everyone involved knows about all your conditions and medicines.