Women taking the most common formof hormone replacement therapy (HRT)may experience 10% to 30% more hearingloss, compared with similar womennot taking HRT, according to a recentstudy published by the Proceedings ofthe National Academy of Sciences.Researchers suggested that HRT thatincluded progestin, the synthetic form ofthe hormone progesterone, possiblyaccelerated normal age-related hearingloss. The study included 124 women takingprogestin and showed that they hadthe hearing of women 5 to 10 yearsolder. The study team consisting of scientists,nurses, and audiologists tested thehearing of 124 healthy women betweenthe ages of 60 and 86. The women weredivided into 3 groups: those who hadtaken HRT that included only estrogen,those who had taken both estrogen andprogestin, and those who had neverbeen on HRT. All the women were testedwith a standard "pure tone" test tomeasure which frequencies they couldhear, as well as with more advancedtests to determine how healthy the earswere and how the brain deciphers thesignals received from the ears. In allmeasures, women whose HRT includedprogestin had worse hearing than theother groups, showing problems not onlyin the inner ear, but in the portions of thebrain used for hearing. Researchers hadanticipated that the estrogen groupwould actually show improved hearing,but that was not the case. Senior authorRobert D. Frisina, PhD, said, "In light ofthese findings, we feel that hearing lossshould be added to the list of negativethings to keep in mind when talkingabout HRT." Further studies are underway to determine how progestin affectsthe ears and brain.
Ms. Farley is a freelance medicalwriter based in Wakefield, RI.