Predicting & Preventing Relapse in Depression

Medical Reviewer

Those of you familiar with my Shareposts may know that I live and work in the UK. I was therefore very pleased to see the UK government is preparing to announce a major shift in health policy in order to tackle depression. The announcement will broaden the range of psychological therapies available for doctors to recommend for their patients and will elevate the 'status' of depression as  equivalent to heart disease. In this Sharepost I'm stopping to take a look at just how significant a problem depression and particularly relapse, actually is.

It is estimated that as many as 85 per cent of people who experience a major depressive episode will have at least one additional episode. The duration of a depressive episode represents a significant chunk out of the lives of individuals. In one 20 year study of unipolar depression, the average number of depressive episodes was found to be between five or six. Effectively, 20 per cent of the life of an individual in this period was taken over by depression.

Without doubt the strongest predictor of depression is past depression. In patients with three or more episodes the relapse rate can be as high as 40 per cent within three months of recovery. People with recurrent depression who are removed or who take themselves off medication have a 70 per cent chance of relapse within six months.

After the first episode of depression, the longer a person goes without a relapse, the less likely it is they will develop a further episode. Relapse rates are around 20 per cent within two months, 30 per cent at around six months, 40 per cent at one year and 50 per cent at two years.

There have also been studies into the demographic characteristics of relapse. Young women may be particularly prone to relapse, although findings are not fully consistent in this regard. Adolescent onset is associated with a high risk of relapse within a year of onset. Age does seem significant in the sense that age of onset before the age of 40 is a fairly good predictor of the chances of relapse.

Roughly a quarter of people with depression suffer what is known as double depression. Double depression occurs when an individual who suffers from persistent mild depression falls into a major depressive state. Relapse rates in such cases can be as high as 50 per cent within one year.

Depression has a huge effect on society. The World Health Organization has warned that within 20 years more people in the world will be affected by depression than any other disease.

A lot of the focus of the UK strategy is expected to be on prevention and recognizing the signs of relapse. Schools are expected to be targeted as is more help in the workplace.


Depression targeted in government policy shift. (2009, December 07). Retrieved from

Hammen, C. (2002) Depression. Psychology Press.