After HRT, Some Health Risks Remain
Researchers Examine Pros and Cons of Hormone Replacement Therapy
WebMD News Archive
HRT and Health Risks: Findings
"We have some good news," says Rowan T.Chlebowski, MD, PhD, a
medical oncologist at the Los Angeles Biomedical Research Institute in
California and another study researcher. "The cardiovascular disease risk
really ended once you stopped the hormones."
The risk for cardiovascular problems, including heart attacks, strokes, and
lung blood clots, was comparable for the former users and the nonusers.
While former HRT users had 343 such "events," nonusers had 323.
After the HRT was stopped, the risk of fractures was similar among former
users and nonusers, indicating the protective effect of the hormones
disappeared once they were stopped. The rates of colorectal cancer didn't
differ in a significant way between the two groups, either, indicating the
protective effects found with HRT against colorectal cancer disappeared,
The risk of breast cancer stayed elevated during the follow-up. "Women
on HRT had a 27% increased risk" of breast cancer compared to nonusers,
Chlebowski says. While 79 former HRT users developed breast cancer during the
follow-up, 60 nonusers did. However, the differences are not statistically
significant, Chlebowski says.
When looking at the breast cancer risk, say Heiss and Chlebowski, it may
have been a bit too soon for the breast cancer risk to decline. "We do see
a tendency toward the breast cancer risk going down," Heiss tells
The other troubling cancer finding: "Women on HRT had a 24% greater risk
of all [invasive types of] cancer compared to women on placebo," Heiss
says. While 281 of the former HRT users developed cancer during the follow-up,
218 nonusers did. Still, Heiss says, "that is not overly alarming."
Chlebowski says the finding is "concerning" and warrants more study.
Why other cancers, including lung
cancer, were more common among former HRT users than nonusers is a mystery,
Another Expert Weighs In
The new study does have some good news, says James Liu, MD, chairman of
obstetrics and gynecology at MacDonald Women's Hospital, Case Medical Center,
University Hospitals, Cleveland, who reviewed the findings for WebMD. Until
2001, Liu was one of the principal investigators for the Women's Health
"The good news is that the effects for the vast majority of side effects
appear to reverse," he says. "The breast cancer issue may take longer