Hormone Therapy May Harm Hearing
Progestin seems to be the culprit, study finds
TUESDAY, Sept. 5, 2006 (HealthDay News) -- Add another item to the list of ailments linked with mid-life hormone replacement therapy: hearing loss.
Researchers have confirmed prior, preliminary findings that postmenopausal women taking progestin as part of hormone replacement therapy (HRT) experienced greater hearing loss than women taking estrogen alone or no hormones at all.
"When a woman goes to her doctor to decide whether she wants to take HRT, this should really be another negative on that list," said Robert D. Frisina, senior author of the study and associate chair of otolaryngology at the University of Rochester Medical School. "If the woman had some hearing loss to begin with, she might want to be more careful," he said.
Age-related hearing loss is the leading communication disorder and among the top three chronic medical conditions in elderly people, the authors noted.
Meanwhile, HRT has recently been linked to an increased risk of breast cancer, heart attacks, stroke, dementia and perhaps even asthma. The use of estrogen alone or in combination with progestin has been widely used to relieve the symptoms of menopause, such as night sweats and hot flashes.
HRT's effect on sensory function, on the other hand, is not yet well understood.
"We're most interested in why people lose hearing as they get older," Frisina said. "We're trying to separate out what is really due to just aging and how much is due to other things like noise exposure or other medical conditions, or things like HRT."
This report was published in the current issue of Proceedings of the National Academy of Sciences. Previous data from the study were presented Feb. 24 at the Association for Research in Otolaryngology's annual meeting, in Daytona, Fla.
Frisina and his colleagues looked at 124 healthy, postmenopausal women aged 60 to 86. The women were divided into three groups: those taking estrogen plus progestin, those taking estrogen alone, and those not taking any hormones. All participants had undergone multiple hearing tests.
Women taking both estrogen and progestin had poorer speech perception than women in the other two groups. The problem was evident both with background noise and in quiet, suggesting that the issue involved both the inner ear and regions of the brain used for hearing.
"Things went wrong in the ear, and something went wrong in the brain, and these could be clinically noticeable. The woman could notice them herself," Frisina said.
It's not clear why HRT has this effect. "Generally, estrogen is beneficial to nerve cells but it looks like that, for hearing, the negative effects of progestin outweigh the positive effects that might occur with estrogen," Frisina said.
Right now, most doctors are recommending only short-term use of HRT for women who have severe symptoms of menopause. "This data could be important for certain people and should be taken into consideration when making a decision," Frisina said.
Learn more about hearing loss from the National Institute on Deafness and Other Communication Disorders, while the National Women's Health Information Center can tell you about hormone therapy.