Depression: What is it?

It's natural to feel down sometimes, but if that low mood lingers day after day, it could signal depression. Clinical depression is an episode of sadness or apathy along with other symptoms that lasts at least two consecutive weeks and is severe enough to interrupt daily activities. Depression is not a sign of weakness or a negative personality. It is a major public health problem and a treatable medical condition.

Shown here is a PET scan revealing "hot spots" of increased activity in the brain of a person who is not depressed.

Depression symptoms: Emotional

The primary symptoms of depression are a sad mood and/or loss of interest in life. Activities that were once pleasurable lose their appeal. Patients may also be haunted by a sense of guilt or worthlessness, lack of hope and recurring thoughts of death or suicide. 

Depression symptoms: Physical

Depression is often associated with physical symptoms. These include:

• Fatigue and decreased energy
• Insomnia, especially early morning waking
• Excessive sleep
• Persistent aches or pains, headaches, cramps or digestive problems that do not ease even with treatment

Depression can make other health problems feel worse, particularly chronic pain. Key brain chemicals influence mood and pain. Treating depression has been shown to improve co-existing illnesses.

Depression symptom: Appetite

Changes in appetite or weight are another hallmark of depression. Some patients develop increased appetite, while others lose their appetite altogether. Depressed people may experience significant weight loss or weight gain.

Impact on daily life

Without treatment, the physical and emotional turmoil brought on by depression can derail careers, hobbies and relationships. Depressed people often find it difficult to concentrate and make decisions. They turn away from previously enjoyable activities, including sex. In severe cases, depression can become life-threatening.

Suicide warning signs

People who are depressed are more likely to attempt suicide. Warning signs include talking about death or suicide, threatening to harm themselves or engaging in aggressive or risky behaviour. Anyone who appears suicidal should be taken very seriously. Do not hesitate to call the Samaritans on 08457 909090.

Depression: Who’s at risk?

Anyone can become depressed, but many experts believe genetics play a role. Having a parent or sibling with depression increases your risk of developing the disorder. Women are twice as likely as men to become depressed.

Causes of depression

Doctors aren't sure what causes depression, but a prominent theory is altered brain structure and chemical function. Chemicals called neurotransmitters become unbalanced. What pushes these chemicals off course? One possibility is the stress of a traumatic event, such as losing a loved one or a job. Other triggers could include certain medications, alcohol or substance abuse, hormonal changes or even the season.

Illustrated here are neurons (nerve cells) in the brain communicating via neurotransmitters.

Seasonal depression

If your mood matches the season - sunny in the summer, gloomy in the winter - you may have a form of depression called seasonal affective disorder (SAD). The onset of SAD usually occurs in the late autumn and early winter, as the daylight hours grow shorter. SAD is thought to affect 7% of people in the UK.

Postnatal depression

The "baby blues" strikes around eight out of 10 new mothers, but one in 10 develop a more intense dark mood that lingers even as their baby thrives. This is known as postnatal depression, and the symptoms are very similar to those of clinical depression. An important difference is that the baby's well-being is also at stake. A depressed mother may have trouble enjoying and bonding with her infant.

Depression in children

Depression or anxiety clouds the days of as many as 4% of UK children. It interferes with the ability to play, make friends and finish schoolwork. Symptoms are similar to depression in adults, but some children may appear angry or engage in risky behaviour, called "acting out." Depression can be difficult to diagnose in children.

Diagnosing depression

As of yet, there is no blood test for depression. To make an accurate diagnosis, doctors rely on a patient's description of the symptoms. You'll be asked about your medical history and medication, alcohol and drug use since these may contribute to your symptoms of depression. Discussing moods, behaviours and daily activities can help reveal the severity and type of depression. This is a critical step in determining the most effective treatment.

Talking therapy for depression

Studies suggest different types of talking therapy can fight mild to moderate depression. Cognitive behavioural therapy aims to change thoughts and behaviours that contribute to depression. Interpersonal therapy identifies how your relationships impact your mood. Psychodynamic psychotherapy helps people understand how their behaviour and mood are affected by unresolved issues and unconscious feelings. Some people find a few months of therapy are all they need, while others find they need longer.

Medication for depression

Antidepressants affect the levels of brain chemicals, such as serotonin and noradrenaline. Allow antidepressants a few weeks of use to take effect. Good follow-up with your doctor is important to evaluate the medication's effectiveness and make dosage adjustments. If the first medication tried doesn't help, there's a good chance another will. The combination of talking therapy and medication appears particularly effective.

Exercise for depression

Research suggests exercise is a potent weapon against mild to moderate depression. Physical activity releases endorphins that can help boost mood. Regular exercise is also linked to higher self-esteem, better sleep, less stress and more energy. Any type of moderate activity, from swimming to housework, can help. Choose something you enjoy and aim for 150 minutes spread across at least five days a week.

Light therapy (phototherapy)

Light therapy has shown promise as an effective treatment not only for SAD but for some other types of depression as well. It involves sitting in front of a specially designed light box for a prescribed amount of time each day. Light therapy may be used in conjunction with other treatments. Talk to your doctor about getting a light box and the recommended length of time for its use.

St John's Wort for depression

St John's Wort is a traditional herbal remedy used to help relieve symptoms of slightly low mood and mild anxiety. There is some evidence that it can fight mild depression, but two large studies have shown it is ineffective against moderately severe depression. Any herbal supplement can interact with other medications you may be taking for medical conditions or contraception, so always talk to your doctor before taking this or any other supplement.  

Pets for depression

A playful puppy or chatty parrot is no substitute for medication or talking therapy, but researchers say pets can ease the symptoms of mild to moderate depression in many people. Pets provide unconditional love, relieve loneliness and give people a sense of purpose. Studies have found pet owners to have less trouble sleeping and better overall health.

The role of social support

Because loneliness goes hand-in-hand with depression, developing a social support network can be an important part of treatment. This may include joining a support group, finding an online support community or making a genuine effort to see friends and family more often. Even joining a book club or taking classes at your gym can help you connect with people regularly.

Vagus nerve stimulation (VNS)

Vagus nerve stimulation (VNS) can help patients with treatment-resistant depression that does not improve with medication. VNS is like a pacemaker for the brain. The surgically implanted device sends electrical pulses to the brain through the vagus nerve in the neck. These pulses are believed to ease depression by affecting mood areas of the brain.

Electroconvulsive therapy (ECT)

The NHS says electroconvulsive therapy (ECT) works for severe depression, but it is only used when antidepressants and other treatments haven't worked. This treatment uses electric charges to create a controlled seizure. However, the effects may not be permanent and some people may experience unpleasant side effects, including headaches, memory problems, nausea and muscle aches.

Transcranial magnetic stimulation

A newer option for people with stubborn depression is repetitive transcranial magnetic stimulation (rTMS). This treatment aims electromagnetic pulses at the skull. It stimulates a tiny electrical current in a part of the brain linked to depression. rTMS does not cause a seizure and appears to have few side effects, but doctors are still fine-tuning this treatment.

Good outlook

In the midst of depression, you may feel hopeless and helpless, but the fact is, this condition is highly treatable. More than 80% of people get better with medication, talking therapy or a combination of the two. Even when these therapies fail to help, there are cutting-edge treatments that fill the gap.

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