SAN FRANCISCO, June 21 - Increased levels of the stress hormone cortisol are clearly elevated in child-bearing-aged women who have stopped menstruating - not only in the bloodstream, but also in the cerebrospinal fluid, a senior researcher at the Magee-Womens Research Institute has found. The study is significant because it shows a definitive link between cortisol levels in circulating blood and those in the fluid that surrounds and bathes the brain and spinal cord.
"In fact, cortisol levels in the cerebrospinal fluid are even higher than in the circulating bloodstream," said Sarah Berga, M.D., a professor in the departments of obstetrics, gynecology and reproductive sciences and psychiatry at the University of Pittsburgh School of Medicine and a senior investigator at Magee-Womens Research Institute. "This is really important because cortisol is neurotoxic."
Benedetta Brundu, an obstetrics and gynecology resident in Padua, Italy, who participated in a research exchange program in Dr. Berga's Pittsburgh laboratory, presented the study findings today at the 84th Annual Meeting of the Endocrine Society, an organization made up of endocrine specialists in internal medicine, pediatrics and gynecology.
"This is one of these 'Why treat stress?' stories," said Dr. Berga, senior study author, who is also director of the division of reproductive endocrinology and infertility at the Magee-Womens Hospital of UPMC Health System.
For more than 15 years, Dr. Berga has been studying functional hypothalamic amenorrhea (FHA), a condition that affects some 5 percent of women in their reproductive years. It is characterized by wildly irregular or absent periods - often for as long as two years or more. For the most recent study, Drs. Berga, Brundu and their colleagues looked at 22 women with FHA and 24 women with normal menstrual cycles. The women who participated were of similar age and body-mass index.
What the researchers found was that women with FHA exhibited free cortisol concentrations in cerebrospinal fluid that were 30 percent greater than those among women with normal periods. Serum cortisol levels were 23 percent higher in women with FHA.
"What this means is that stress in women with FHA affects more than fertility," said Dr. Berga. "We continue to learn more about the long-term consequences of stress."
In addition to Drs. Berga and Brundu, study authors include Tammy L. Loucks, M.P.H., and Judy L. Cameron, Ph.D.
Funding for the study was provided by the National Institutes of Health (NIH).
Magee-Womens Research Institute, the country's first research institute devoted to women and infants, was formed in 1992 by Magee-Womens Hospital of UPMC Health System. The University of Pittsburgh School of Medicine's department of obstetrics, gynecology and reproductive sciences is one of the top three funded NIH departments in the nation.