A number of studies suggest a role for depression in many other medical conditions, especially in worsening an illness once it has taken hold. The evidence is mounting that for patients with serious disease who are depressed , it would pay medically to treat their depression too.
Eighty percent of heart attack patients attribute their illness to factors they feel they cannot change- such as worry, stress or overwork- and such beliefs have shown to cause further anxiety and depression. And depression does appear to double the risk of premature death. In a study of two thousand eight hundred and thirty two middle aged men and women tracked for twelve years, those who felt a sense of nagging despair and hopelessness had a heightened rate of death from heart disease. For the three percent or so who were most severely depressed, the death rate from heart disease, compared to the rate for those with no feelings of depression, was four times greater.
Depression seems to pose a particularly grave medical risk for heart attack survivors. In a study of patients in a Montreal hospital who were discharged after being treated for a first heart attack, depressed patients had a sharply higher risk of dying within the following six months. Among the one in eight patients who were seriously depressed, the death rate was five times higher than for others with comparable disease - an effect as great as that of major medical risk for cardiac death, such as left ventricular dysfunction or a history of previous heart attacks. Among the possible mechanisms that might explain why depression so greatly increases the odds of a later heart attack are its effects on heart rate variability, increasing the risk of fatal arrhythmias.
Of hundred patients who received bone marrow transplants, twelve of the thirteen who had been depressed died within the first year of transplant, while thirty four of the remaining eighty seven were alive two years later. In patients with chronic kidney failure who were most likely to die within the following two years: depression was a stronger predictor of death than any medical signs.
Professor Lewin, whose work was funded by the British Heart Foundation, has concrete evidence showing that graduates of his heart disease rehabilitation programme (currently used in eighty NHS hospitals) need less medical treatment and often recover more swiftly than expected. Coping strategies include learning to over-ride negative thoughts of hopelessness, with positive thinking, combined with a physical fitness programme, relaxation, breathing and yoga exercises. He has now developed a a similar programme for angina sufferers, having found that fourteen angina patients out of a control group of twenty eight did so well after rehabilitation that they no longer needed surgery.
In a study of patients whose condition was so dire that they were among the top ten percent of those using medical services - often because of suffering multiple illness, such as both heart disease and diabetes - about one in six had a serious depression. When these patients were treated for the problem, the number of days per year that they were disabled dropped from seventy nine to fifty one for those who had major depression, and from sixty two days per year to just eighteen in those who had been treated for mild depression.
Yet each successive generation worldwide since the start of this century has lived with a higher risk than their parents of suffering a major depression- not just sadness, but a paralysing listlessness, dejection and self pity, and overwhelming hopelessness - over the course of life. For those who were born after 1955, the likelihood they will suffer a major depression at some point in life is, in many countries, three or four times greater than for their grandparents. In Britain, it is currently estimated that one in five women and one in ten men suffers from depression at some point in their lives -and these episodes are beginning at earlier and earlier ages.
Review compiled Adam Michael Sanders