FRIDAY, Nov. 7, 2003 (HealthDayNews) -- In experiments with cats, researchers found the animals who suffered from interstitial cystitis had smaller adrenal glands than those without the condition.
The finding could lead to new treatments for the chronic, painful pelvic disorder that affects more than 700,000 people in the United States, 90 percent of them women.
Interstitial cystitis is a chronic inflammatory condition of the bladder wall. Symptoms include urinary urgency and frequency, difficulty urinating, minimal urine output and pain in the bladder and/or the urethra that is temporarily relieved by voiding. In some patients, pain may radiate to the genitals, rectal area and thighs.
"In cats that have interstitial cystitis, which appears to be the same in cats as in humans, two of the four zones of their adrenal glands are unusually small," says lead researcher Dr. Tony Buffington, a professor of veterinary clinical sciences at Ohio State University.
In their study, Buffington and his colleagues compared the adrenal glands of 13 cats that had interstitial cystitis with eight cats that did not have the disorder.
The adrenal glands of the cats with interstitial cystitis were about half the size of the adrenals in the normal cats, according to the report in the December issue of the Journal of Urology.
The adrenal glands sit next to the kidneys and produce hormones that, among other things, help regulate heart rate and blood pressure.
The researchers found that when cats were injected with the stress-inducing compound adrenocorticotropic hormone, those with interstitial cystitis produced lower levels of the stress hormone cortisol, which is produced in the adrenals.
Under normal conditions, the functioning of the adrenal glands in cats with interstitial cystitis appears normal, Buffington says. "It is only under stress that it is abnormal," he adds.
Buffington believes this finding indicates that while there may not be adrenal insufficiency under normal circumstances, there may well be an insufficiency in adrenal reserve during periods of stress.
Interstitial cystitis worsens with stress, Buffington notes. The combination of increased stress and decreased adrenal response may be the reason why, he adds.
These findings may offer a new direction to studying interstitial cystitis in humans that can eventually lead to new treatments, Buffington says.
"Preliminary findings in humans suggest that the same abnormalities in adrenal function may be present in women when the disease is flaring up, but not when the disease is in a quiet state," he notes.
Small adrenal glands may be an underlying risk factor for interstitial cystitis, Buffington speculates.
Interstitial cystitis is a complex disorder and the abnormalities that underlie it are very subtle, Buffington says. These new findings may shed light on the causes of the condition and lead the way to new treatments, he adds.
Dr. Richard Bercik, associate director of urogynecology at Yale University, says that "physicians and lay people need to realize the connection between stress and interstitial cystitis."
"It is not just that stress exacerbates symptoms but also that other diseases associated with stress disorders, for example chronic fatigue syndrome, irritable bowel disease, fibromyalgia, endometriosis, chronic pelvic pain, anxiety, obsessive compulsive disorder, depression, neuralgia, temporomandibular joint (jaw joint) disease, phobias, all can possibly interface with interstitial cystitis," he adds.
Bercik advises that patients with these disorders are at higher risk for interstitial cystitis and should be screened for it.
This study will lead to similar testing in human interstitial cystitis patients, Bercik says. "We know that interstitial cystitis patients have higher norepinephrine levels in the urine, and interstitial cystitis patients with low cortisol in urine tend to have more symptoms."
"These may be two different subgroups, but both point to an altered immune/inflammatory response, which is regulated by the hypothalamic-pituitary-adrenal system," he notes.
More information
To learn more about interstitial cystitis, visit the National Institute of Diabetes and Digestive and Kidney Diseases and the National Library of Medicine.
