Heart disease too seems to be exacerbated by depression. In a study of 2,832 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.32 And for the 3 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.33 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 risks 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.
Depression has also been found to complicate recovery from hip fracture. In a study of elderly women with hip fracture, several thousand were given psychiatric evaluations on their admission to the hospital. Those who were depressed on admission stayed an average of eight days longer than those with comparable injury but no depression, and were only a third as likely ever to walk again. But depressed women who had psychiatric help for their depression along with other medical care needed less physical therapy to walk again and had fewer rehospitalizations over the three months after their return home from the hospital.
Likewise, in a study of patients whose condition was so dire that they were among the top 10 percent of those using medical services—often because of having multiple illnesses, such as both heart disease and diabetes—about one in six had serious depression. When these patients were treated for the problem, the number of days per year that they were disabled dropped from 79 to 51 for those who had major depression, and from 62 days per year to just 18 in those who had been treated for mild depression.34
THE MEDICAL BENEFITS OF POSITIVE FEELINGS
The cumulative evidence for adverse medical effects from anger, anxiety, and depression, then, is compelling. Both anger and anxiety, when chronic, can make people more susceptible to a range of disease. And while depression may not make people more vulnerable to becoming ill, it does seem to impede medical recovery and heighten the risk of death, especially with more frail patients with severe conditions.
But if chronic emotional distress in its many forms is toxic, the opposite range of emotion can be tonic—to a degree. This by no means says that positive emotion is curative, or that laughter or happiness alone will turn the course of a serious disease. The edge positive emotions offer seems subtle, but, by using studies with large numbers of people, can be teased out of the mass of complex variables that affect the course of disease.
The Price of Pessimism—and Advantages of Optimism
As with depression, there are medical costs to pessimism—and corresponding benefits from optimism. For example, 122 men who had their first heart attack were evaluated on their degree of optimism or pessimism. Eight years later, of the 25 most pessimistic men, 21 had died; of the 25 most optimistic, just 6 had died. Their mental outlook proved a better predictor of survival than any medical risk factor, including the amount of damage to the heart in the first attack, artery blockage, cholesterol level, or blood pressure. And in other research, patients going into artery bypass surgery who were more optimistic had a much faster recovery and fewer medical complications during and after surgery than did more pessimistic patients.35
Like its near cousin optimism, hope has healing power. People who have a great deal of hopefulness are, understandably, better able to bear up under trying circumstances, including medical difficulties. In a study of people paralyzed from spinal injuries, those who had more hope were able to gain greater levels of physical mobility compared to other patients with similar degrees of injury, but who felt less hopeful. Hope is especially telling in paralysis from spinal injury, since this medical tragedy typically involves a man who is paralyzed in his twenties by an accident and will remain so for the rest of his life. How he reacts emotionally will have broad consequences for the degree to which he will make the efforts that might bring him greater physical and social functioning.36
Just why an optimistic or pessimistic outlook should have health consequences is open to any of several explanations. One theory proposes that pessimism leads to depression, which in turn interferes with the resistance of the immune system to tumors and infection—an unproven speculation at present. Or it may be that pessimists neglect themselves—some studies have found that pessimists smoke and drink more, and exercise less, than optimists, and are generally much more careless about their health habits. Or it may one day turn out that the physiology of hopefulness is itself somehow helpful biologically to the body's fight against disease.
With a Little Help From My Friends:
The Medical Value of Relationships
Add the sounds of silence to the list of emotional risks to health—and close emotional ties to the list of protective factors. Studies done over two decades involving more than thirty-seven thousand people show that social isolation—the sense that you have nobody with whom you can share your private feelings or have close contact—doubles the chances of sickness or death. 37 Isolation itself, a 1987 report in Science concluded, "is as significant to mortality rates as smoking, high blood pressure, high cholesterol, obesity, and lack of physical exercise." Indeed, smoking increases mortality risk by a factor of just 1.6, while social isolation does so by a factor of 2.0, making it a greater health risk.38
Isolation is harder on men than on women. Isolated men were two to three times more likely to die as were men with close social ties; for isolated women, the risk was one and a half times greater than for more socially connected women. The difference between men and women in the impact of isolation may be because women's relationships tend to be emotionally closer than men's; a few strands of such social ties for a woman may be more comforting than the same small number of friendships for a man.
Of course, solitude is not the same as isolation; many people who live on their own or see few friends are content and healthy. Rather, it is the subjective sense of being cut off from people and having no one to turn to that is the medical risk. This finding is ominous in light of the increasing isolation bred by solitary TV-watching and the falling away of social habits such as clubs and visits in modern urban societies, and suggests an added value to self-help groups such as Alcoholics Anonymous as surrogate communities.
The power of isolation as a mortality risk factor—and the healing power of close ties—can be seen in the study of one hundred bone marrow transplant patients.39 Among patients who felt they had strong emotional support from their spouse, family, or friends, 54 percent survived the transplants after two years, versus just 20 percent among those who reported little such support. Similarly, elderly people who suffer heart attacks, but have two or more people in their lives they can rely on for emotional support, are more than twice as likely to survive longer than a year after an attack than are those people with no such support.40