Distress May Spur Immune System in AIDS-Infected Men, Study Says
NEW ORLEANS (AP) _ Psychological distress may stimulate the disease-fighting immune system in men with early AIDS virus infection, the opposite of its apparent effect in people with full-blown AIDS, a study suggests.
That may mean the impact of anxiety, depression and fatigue depends on how well the immune system is able to respond to such distress, said researcher Lydia Temoshok.
It also fits in with a recent suggestion that the AIDS virus may over- stimulate the immune system early on, leading to its later exhaustion and collapse, she said. If that is true, strategies to spur the immune system of infected people may have to be timed to avoid over-stimulation, she said.
AIDS kills by crippling the body’s immune system, leaving a person vulnerable to fatal illnesses. Some researchers are studying whether programs to help deal with stress can help infected people maintain their immune systems, possibly slowing the progression of the disease or increasing survival times.
Temoshok is a senior scientist at the Walter Reed Army Institute of Research in Washington. She did the new research at the University of California at San Francisco with colleagues there and from the University of California at Los Angeles.
She spoke in an interview before presenting the work Friday at the annual meeting of the American Psychological Association.
Arthur LaPerriere, research assistant professor of psychiatry at the University of Miami School of Medicine, called Temoshok’s study preliminary. But he said it may indicate that psychological intervention can affect the immune systems of people at the stage of infection she studied.
Research at his school found that infected men who had no symptoms showed an increase in immune system white blood cells after participating in a program that included progressive muscle relaxation and psychological therapies, he said.
Temoshok said her work shows only a correlation between distress levels and activity of the immune system, suggesting but not proving any cause and effect.
Previously, her work had linked higher levels of psychological distress with lower levels of immune system activity in men with full-blown acquired immune deficiency syndrome.
But just the opposite relationship appeared in the new study of 103 men who showed at least one AIDS-related symptom but not the full disease.
Distress was measured with standard tests of anxiety, depression and fatigue. Measures of the immune system included numbers of T-cells, which are white blood cells that are a key target of the AIDS virus, and of other white cells. Researchers also measured the potency of immune system blood cells called natural killer cells.
Most immune system measures were significantly higher in men with more anxiety, depression and fatigue, Temoshok said.
Other studies suggest that distress has the opposite effect on healthy people, whose immune systems become depressed.
The researchers do not yet know if the stimulated immune system has any effect on the progression to full-blown AIDS, she said. So it is not clear what psychological treatment, if any, would be useful, she said.
A possible explanation for the divergent findings of the two studies is that the impact of distress may depend on the immune system of a person infected with the AIDS virus, she said.
Perhaps the relatively well-functioning immune system of a person with only early AIDS symptoms responds by being stimulated, while the more crippled immune system of a person with full-blown AIDS can only be suppressed, she said.