March 4, 2008 -- CHICAGO (AP) - The first follow-up of a landmark study ofhormone use after menopause shows heart problems linked with thepills seem to fade after women stop taking them, while surprisingnew cancer risks appear.
That heart trouble associated with hormones may not be permanentis good news for millions of women who quit taking them after thegovernment study was halted six years ago because of heart risksand breast cancer.
But the new risks for other cancers, particularly lung tumors,in women who'd taken estrogen-progestin pills for about five yearspuzzled the researchers and outside experts.
Those risks "were completely unanticipated," said Dr. GerardoHeiss of the University of North Carolina in Chapel Hill, leadauthor of the follow-up analysis.
The analysis focused on participants' health in the first two tothree years after the study's end. During that time, those who'dtaken hormones but stopped were 24 percent more likely to developany kind of cancer than women who'd taken dummy pills during thestudy.
"There's still a lot of uncertainty about the cause of theincreased cancer risk," said analysis co-author Dr. JoAnn Manson,chief of preventive medicine at Harvard's Brigham and Women'sHospital.
The cancers included breast tumors, which also occurred morefrequently in hormone users during the study.
The researchers noted that the increased risks for all cancersamounted to only three extra cases per year for every 1,000 womenon hormone pills, compared with nonusers.
Still, Heiss said the results suggest that former hormone usersneed to be vigilant about getting cancer screening includingmammograms.
"Vigilance is justified," he said. "No alarm, butvigilance."
The initial study of 16,608 postmenopausal women was designed toexamine pros and cons of taking pills long thought to benefitwomen's health. It was halted in 2002 when more breast cancers,heart attacks and related problems were found in hormone usersversus nonusers.
There were some health benefits - decreased risks for hipfractures and colorectal cancer - but the follow-up found thosealso faded after women stopped the pills.
Some data suggest that U.S. breast cancer rates have declinedsince the study's end. But that likely reflects fewer womenstarting on the pills rather than any decline in breast cancer riskamong past users, said Dr. Michael Lauer of the National Heart,Lung and Blood Institute at the National Institutes of Health,which conducted and funded the landmark research.
The authors said the new results send the same message they'vebeen advocating ever since the study ended: Health risks fromestrogen-progestin pills outweigh their benefits, and they shouldonly be used to relieve hot flashes and other menopause symptoms,in the lowest possible dose for the shortest possible duration.
The new analysis appears in Wednesday's Journal of the AmericanMedical Association.
A spokesman for Wyeth Pharmaceuticals, maker of the Premproestrogen-protestin pills used in the study, voiced a criticismfrequently cited by scientists, too - that participants were intheir 60s on average, at least 10 years old than typical hormoneusers. The latest results thus may not apply to typical usersbecause older women have different health risks than younger ones,including more cancers in general, said Wyeth's Dr. Joseph Camardo.
Prempro's packaging information already recommends routinebreast exams and mammograms for users, and Camardo said thefollow-up results are "not anything that's particularly new thatshould change guidance."
Manson, the co-author, said it's possible the initial studyresults prompted hormone-using participants to see their doctorsmore often than nonusers after the study ended, which could haveresulted in more cancers detected.
It's also possible hormones either triggered new tumors orfueled the growth of existing ones, the researchers said.
"Once a tumor gets started, you might think of it as a train isout of the station and it might be more difficult to stop it,"Lauer said.
The follow-up involved 15,730 participants tracked through March2005.
The authors said the decline in heart problems was notsurprising, since harmful effects of hormones on blood vesselscould be expected to fade after women stopped taking the pills.Also, heart risks during the study were highest soon after womenstarted taking hormones.
Dr. Sherry Nordstrom, an obstetrician-gynecologist at theUniversity of Illinois at Chicago, said the lung cancers were asurprising finding but called hormones "still very appropriatetherapy" for women with bad symptoms.
Study participant Geraldine Boggs, a Washington, D.C. nurse withthree daughters and four granddaughters, said women should payattention to the new findings.
"I initially joined the study to make sure that my daughtersand granddaughters had informed choices about taking them when theygot to be my age," said Boggs, 64.
Boggs, in her early 50s when she enrolled, was assigned to takehormones. Still, she said she developed no health problems duringthe study or afterward, other than hot flashes for about a yearafter quitting the pills.
Dr. Nieca Goldberg, a New York University women's heartspecialist, said the study underscores that in addition to cancerscreening, women who stop taking hormones need to find other waysto keep their bones strong, including getting more calcium andexercise.
On the Net:
Hormone study: http://www.nhlbi.nih.gov/whi/estro-pro.htm
(Copyright 2008 by The Associated Press. All Rights Reserved.)