Depression can be defined as a mental condition which gives rise to symptoms such as feelings of sadness, with a lack of pleasure, interest or motivation, low self-esteem, poor appetite, tiredness or lethargy, poor concentration, poor memory and disturbed sleep. Not all these symptoms may be present at the same time.
The problem can run in families and is rarely a one-off experience as it is usually long-standing or recurrent. Ability to cope with daily family life and work may be affected.
Ordinary situations such as going to the shops can become a major exercise or a traumatic experience. This causes many with the condition to retreat into themselves and their home, as they find it difficult to venture outside.
Many sufferers of depression have periods where they feel rejected, worthless or guilty. It can seem that there is no way to escape the problem. These feelings may sometimes develop into thoughts of suicide.
Many people use the expression ‘depression’ lightly, but it is important that we separate clinical depression from episodes of low mood. Depression is a severe medical condition which requires the attention of a doctor.
Many of us will have experienced feeling a bit sad, ‘fed up’ or down during some period of our lives. While often unpleasant, this is a normal part of being human. Low moods tend to be more easily resolved – being surrounded by people you like or hearing good news can be all it takes to cheer oneself up. The same, however, cannot be said of depression.
Mood is a complex phenomenon, and scientists have yet to work out exactly why people experience different moods. What we know is that our mood is largely controlled by chemicals in our brain, known as neurotransmitters.
For example, it has been shown that there is a direct relationship between our mood and levels of serotonin in the brain. Some people naturally have lower levels of serotonin making them more prone to bouts of low mood or mild depression. It is also suggested that the levels of serotonin and other neurotransmitters can define our personalities – some people are naturally more outgoing and ebullient, whilst others are more introspective and quiet.
However, depression is a far more complex condition than one which can be simplified to the quantity of a certain chemical in the brain. There are a number of factors which can lead to depression. These do not apply to every person and their effects vary from one to another. These factors may be divided into three categories:
- Biological factors – there is a large variety of biological factors which may lead to low mood or depression, including the chemical imbalances already described. Hormone levels, for example, can profoundly affect mood. In women, this can be seen during the normal menstrual cycle, such as with pre menstrual syndrome, as the hormones oestrogen and progesterone fluctuate. Depression or mood swings can also be symptoms experienced during the menopause
- Genetic factors – depression can run in families. This is most likely to be because your genes hold information controlling cell structure and function, including the amount of serotonin produced. It is thought that you are up to six times more likely to develop depression if you have a family history of the condition
- External factors – these are factors which are not related to the natural neurological state of the mind. The most obvious example of this is that certain types of prescribed medicine can affect your mood. If this is the case with you, work with your doctor to find a solution or alternative medication.
The causes of depression described above determine whether or not one is likely to be prone to low mood or depression. Actual episodes of depression or worsening of the condition may arise as a result of triggers. These include:
- Bereavement – anyone suffering the loss of a loved one will find it a difficult time. Bereavement affects people in different ways. Most will of course feel terribly sad and recover given time, going through the normal process of grieving. However, some people slip into feelings of depression which can last for many months or years
- Empty nest – some people describe the time when some or all of their children leave home as being similar to bereavement. The change of routine, with a feeling of ‘emptiness’ in the house can be a very unsettling time
- Alcohol – this can cause depression in many addicts or regular drinkers. Those prone to depression may use alcohol as a temporary solution to their ‘problems’ but in the long run, alcohol and other addictive substances simply amplify the problem
- Loss of job – becoming unemployed can be very difficult for most. Along with the inevitable money worries, it creates uncertainty in one’s life and potentially, a loss of confidence.
- Stress – a wide range of other factors, ranging from money worries, relationship or family problems to problems at work,can lead to the feeling of being under stress, or anxiety, triggering depression.
The triggers described above are the same as those leading to low mood and it is important to separate these normal episodes of feeling low from depression which is a medical condition.