STUDY SHOWS STRESS PLAYS HAVOC WITH HORMONES, WEAKENING IMMUNITY
COLUMBUS, Ohio -- The body's endocrine system may be one of the first victims of the stress brought on by a couple's marital arguments.
The levels of hormones that normally promote or reduce immune function change dramatically only moments after the first hostile charges are hurled.
The evidence, reported in the journal Psychosomatic Medicine this month by a group of Ohio State University researchers, is the latest in a series of findings concerning how psychological stress affects our bodies.
A related study last year of newlywed couples showed significant changes in a group of immune function markers -natural killer cells, viral antibodies and T-lymphocytes -- after the couples discussed sensitive topics. The changes in hormone levels in this study were at least equal to those of the other markers.
"The endocrine system produces hormones which affect organs throughout the entire body," explains William Malarkey, professor of internal medicine and medical microbiology and immunology, and leader of the research group. "While we're interested in the effects on immunity, these changes probably affect health in other ways as well."
Malarkey; Janice Kiecolt-Glaser, professor of psychiatry and psychology, and Ronald Glaser, professor of medical microbiology and immunology, looked at the way six of these hormones -cortisol, prolactin, norepinephrine, epinephrine, growth hormone and ACTH -- react to a psychologically stressful event.
This latest study and its earlier counterpart surprised the researchers. They had predicted that there would be little if any change among the research subjects since newlyweds are considered more amiable and less hostile than older couples. The study showed, however,definite physiological effects of psychological stress.
"We used what could be considered the worst possible group for this study. These were highly healthy people. They were blissful!" explained Malarkey. In assembling their experiments, the researchers excluded more than 90 percent of the couples who had originally volunteered because of weight, behaviors or other health reasons.
Ninety newlywed couples took part in the study. They had an average age of 25 and tended to be well-educated and reasonably well-off financially -- the average combined annual income for each couple was about $43,000. Most couples had dated for about three years beforethey married, and three out of five had lived together before getting married.
The couples each spent 24 hours in the university's Clinical Research Center, during which time blood samples were taken for later analysis of hormone levels and other immune function markers. After a short discussion with a member of the research team, the couples were asked to discuss a topic which they had identified as causing problems in their marriage.
The participants each had an IV inserted so that samples could be taken without interfering with their discussion. The couples were characterized as either "high-hostile" or "low-hostile" groups based on scoring of their videotaped interviews.
When the data was compiled, the researchers found the following:
--Couples in the low-hostile group showed a drop in two of the four hormones considered to be immune system inhibitors. Both epinephrine (or adrenaline) and ACTH dropped in this group during the experiment, while another immune inhibitor, norepinephrine, rose slightly but then held steady. Levels of the immune-enhancing hormone prolactin increased in the low-hostile group. And levels of growth hormone, another enhancer, dropped in this group.
--The high-hostile group showed almost opposite results. Immune inhibitors epinephrine, norepinephrine and ACTH either rose or stayed high. The immune-enhancing hormone prolactin dropped while growth hormone rose.
Levels of the sixth hormone, cortisol, thought to be the most potent immune system inhibitor, remained constant regardless of which group was tested. Researchers have known that stress can negatively affect some parts of the immune system, Malarkey said.
"Now we know something of the toll it can take on the endocrine system. But since these hormones perform other functions in the body, the stress-caused changes may create other health problems as well." He suggests that aging and a number of diseases may be equally affected bystress-based hormone changes.
"We can now see where human physiology is disturbed by these changes, but not to the point of causing a disease. That situation may interact with a person's genetic makeup or other underlying disease to later cause a serious health problem," he said.
Malarkey said the findings of this study clearly suggest that people should come up with new strategies for how they handle daily stresses.
"Our inability to deal with stress has a definite negative effect on our health."
Contact: William Malarkey (614) 293-8730
Written by Earle Holland, (614) 292-8384; Holland.firstname.lastname@example.org.