From The Sunday Times, February 14, 1999

I used to deal with mild depressions - feeling low - by going jogging. I had never been seriously depressed until four years ago, following the difficulties I experienced in controlling atrial fibrillation, a common and non-threatening heart disorder. It means the regular rhythm of the heart is lost and, should a blood clot form, there is the danger of a stroke. As a hypochondriac, I was terrified by the prospect and became increasingly anxious as Easter approached, when I was due to go on an important trip to South Africa. I had fantasies of falling ill in a remote, medically primitive environment.

A change in medication gave me what I can only describe as morning sickness followed by severe stomach cramps. I was deteriorating both physically and mentally and felt incapable of travel. I cancelled my trip at the last moment, although doctors saw no reason for me to do so. My distress at not going only increased my anxiety and, after another change of heart drug, I began to feel very weird - I can describe it no other way. Then, quite suddenly, I was unable to sleep at all.

Sleep had never been a problem for me. Now it seemed so impossible that I began to take pills, temazepam, which helped a bit, but it was a dreamless sleep that left me feeling dopey. I found it very difficult to work, even to get out of bed. Through the pain, I realised that I was having a breakdown in the old-fashioned sense.

I became obsessed with the physical symptoms of my illness. I found it increasingly difficult to urinate and begged a urologist to hospitalise me.

Wisely, he did not. But shortly afterwards, I woke up one morning with the overwhelming desire to commit suicide. After several frantic phone calls to doctors, I was admitted to the psychiatric ward of the local hospital. There I was cured by a Prozac-style antidepressant (Seroxat) and cognitive therapy.

In last week's Sunday Times, Bryan Appleyard raised important questions about the cause and cure of depression. He questioned, for example, my emphasis on the biological basis of the illness and my suspicions about psychoanalysis.

Depression, as Appleyard says, is a perilously ambiguous term. There is something of a lumpy continuum between feeling low and anxious - as is common in everyday life - and severe clinical depression, which is a serious illness.

I am convinced my depression had a biological origin and was set off by one of the drugs I was taking. There can be no doubt that depression can have a biological origin. The evidence comes from patients in whom the levels of the hormone cortisol - a stress hormone - is inordinately high. Key evidence also comes from genetics. Studies on twins and families have shown that depression has a heritability of more than 50% - that is, half of the vulnerability to depression is biological.

Of course, Appleyard was right to emphasise that biology is only part of the story. Bereavement increases the probability of a severe depression sevenfold.

Marked parental rejection or neglect, violent treatment from a member of the household or sexual abuse about doubles the chance of a depressive episode in any one year in adult life. But while childhood experiences can have an influence, they are not as great as psychoanalysts would have us believe.

Interesting, imaginative and even seductive though the ideas of psychoanalysts are, they are impossible to validate or disprove - they are little more than anecdotes. Thus Freud believed that a patient who is depressed is mourning for someone who is consciously or unconsciously believed to be lost. The loss can be real, in the case of bereavement. More often, he argued, the patient is angry with the loved one, wishes that person dead, kills the person in fantasy and then mourns the loss.