A Cold Fact: Long -Term Stress Can Make You Side

NEW YORK — Explanations for why people catch colds are almost as numerous as the viruses that cause colds. They range from the environmental — living with small children, riding the subway at rush hour, getting chilled to the bone —to the personal — smoking too much, exercising too little, sleeping poorly, eating erratically, working too hard.

But studies under way at Carnegie Mellon University in Pittsburgh suggest that psychological stress is also a very important factor in determining who gets sick when nasal passages are invaded by a cold-causing virus. Just any old stress will not do. It has to be long-term stress, lasting at least a month and stemming from a significant problem like being fired from a job after years of service or being left financially or emotionally bereft by a divorce.

Dr. Sheldon Cohen, a psychologist at' Carnegie Mellon, has spent years trying to discover why some people frequently catch colds, while others rarely get a sniffle. In 1991, he directed a study of: 394 men and women that identified psychological stress as an important factor.

He and researchers in Britain showed that the higher a people’s stress score on, a standard test, the more likely the person was to develop a cold when exposed to a cold virus. Stress was an important risk factor even when smoking, lack of exercise, poor diet, disturbed sleep and alcohol consumption were considered. In the studies, financed by the National Institute of Mental Health, Dr. Cohen and colleagues at the University Of Pittsburgh School Of Medicine and the University of Virginia Health Sciences Center subjected 276 healthy volunteers aged 18 to 55 to physical, social and psychological examinations before pla­cing them in quarantine and depositing cold viruses in their nasal passages.

Stress lasting more than two years nearly quadrupled the risk. Likewise, the stress of interpersonal difficulties doubled the risk of a cold, and being under work-related stress raised the risk three and a half times. Less common stresses, however, had no effect on participants' chances of developing a cold. Even being socially well-connected, which could provide emotional support during hard times, could not overcomethe harmful effects of chronic severe stress, the researchers reported.

Now, Dr. Cohen and researchers are looking at substances called cytokines that have an indirect effect on tissues that are being invaded. Cytokines are messenger chemicals of the immune system that travel through the blood and send out an inflammatory alarm when cellular abnormalities are discovered. The alarm marshals macrophages and other reinforcements to battle the invader.

This response of the body to a viral infection, not the virus itself, causes the sneezes, congestion, runny nose and other cold symptoms.

New York Times, published: May 12, 1998

Vocabulary: