By LESLIE H. LANG UNC-CH School of Medicine
(EMBARGOED) CHAPEL HILL, N.C. - Researchers at the University of North Carolina at Chapel Hill have shown that men infected with HIV will more rapidly develop AIDS as stressful events accumulate in their lives or if their social supports are weak.
The new findings carry important implications both for understanding the progression of AIDS and possible treatments for HIV, according to Dr. Jane Leserman, research associate professor of psychiatry at the UNC-CH School of Medicine.
"This is perhaps among the most compelling evidence to date linking psychosocial variables with HIV progression," she says. "Along with considering the more biological aspects of AIDS, we should consider the relevance of psychological aspects of this illness".
A report of the study appears in the May issue of the journal Psychosomatic Medicine. Leserman, who is part of a research team of eight scientists from North Carolina, Florida and Pennsylvania, notes that the new findings build upon those reported earlier by her team. They studied 82 HIV-infected gay men over a period of 5 1/2 years. The men first enrolled in the study between 1990 and 1992 and were without AIDS symptoms at that time.
In a two-year follow-up of the group, severe stress and depressive symptoms, especially when they occurred jointly, were associated with greater decreases in immunity -- specifically, some of the immune system's natural killer cells and CD8 T lymphocytes.
"At that point, because we knew that CD8 and natural killer cells were involved in host defenses against viral disease and that CD8 might inhibit HIV-1 replication, we went on to look at the relevance of these findings to disease progression. The results from our current study are the first to link stressful life events with progression to AIDS," Leserman says.
At 5 1/2 years into the study, 33 percent of the men had developed AIDS - that is, their CD4 immune "helper" T cell count dropped below 200 or they developed an AIDS clinical condition. "And what we found was that the men who had more cumulative stressful events and the men who had less cumulative social support were the ones who progressed faster to AIDS," Leserman says.
According to Leserman, who is also a UNC-CH medical sociologist, the measure of stress is unique, not based on self-reported checklist responses. "We ask subjects to tell us about the circumstances in their life every six months. They indicate people who have died, if they've changed jobs, moved or any other such stress that might occur to someone. And we interview them in detail about the circumstances - the financial impact, how close they were to the person who died, how long they lived with the partner before they broke up."
The researchers then apply a numerical rating to these circumstances, based on a manual of vignettes and norms. "In this way we know that the stress measure is independent of the subjects' perceptions and ways of coping. It's a more objective measure," Leserman says. She and her colleagues note, "This objective stress rating helps reduce the possibility that worsening disease may have led to poorer coping and higher stress scores."
Statistical analysis showed that the probability of progressing to AIDS was two to three times higher for HIV-infected men with more than average stress or with less than average social support than for those below the median on stress and above the median on social support.
"We showed that for every increase in cumulative average stressful life events - equivalent to one severe stressful event or two moderate stressful events - the risk of AIDS was doubled," Leserman says.
Was depression a factor in AIDS progression as it was in decreased immune measures? According to the report, depressive symptoms were related to faster progression to AIDS. "However, that dropped out when stressful events and social support were in the equation together," Leserman says. "The stressful event and social support variables seemed to be more robust in relation to progression to AIDS."
If there is a take-home message from these findings, Leserman sees it both in terms of treatment and research.
"We need to shore up social support systems for these men. And for men with stressful events in their lives, perhaps some cognitive-behavioral treatment, psychological support groups, or counseling might be appropriate," she states. "And we need to determine whether interventions that have been shown to reduce stress and improve social support can alter the course of HIV infection."
"It would also be important to determine if the study's findings apply to women," she adds.
The UNC-CH study was supported by separate grants from the National Institute of Mental Health and the National Institutes of Health.
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