Hormone Therapy May Increase Risk Of Blood Clots
Study: Older Age, Obesity Also Boost RiskOct 6, 2004 | www.nbc13.com As if there weren't enough reasons to reconsider hormone replacement therapy, a new study highlights yet another negative health effect of taking estrogen plus progestin to combat the symptoms of menopause.
We already know that hormone replacement therapy can lead to increased risk of breast cancer and other problems. Now, a new study found that estrogen plus progestin doubles a woman's risk of developing certain blood clots.
Two years ago, Gail Berry was sitting at her desk when her leg swelled and ached so badly that she went to the hospital. She found out she had a deep vein thrombosis a blood clot.
"The ultrasound showed it was in the back of my right leg, and I was admitted to the hospital for treatment," Berry said.
Berry, who had been taking estrogen plus progestin, also had a pulmonary embolus, which occurs when part of the blood clot breaks off and travels to the lung. That can be fatal.
A 5½-year study published in Wednesday's issue of the Journal of the American Medical Association came from research that initially was stopped out of concern that estrogen increases the risk for heart attacks and breast cancer. It included about 16,600 women who were randomly assigned to receive either hormone replacement as estrogen with progestin, or a placebo.
Researchers found that 167 women taking the hormone combination developed blood clots, compared to only 76 women taking a placebo.
"The main finding of the study was that women who were assigned to take the hormone replacement therapy had about a doubling of the risk of blood clots compared to women assigned to take placebo," said Dr. Mary Cushman, of the University of Vermont.
Women who are over age 70 and women who are obese are at greatest risk for developing blood clots, or thrombosis, said Cushman, who conducted the study with colleagues from the Women's Health initiative.
"The women who had both obesity and hormone replacement were almost seven times more likely to develop thrombosis, compared to thinner women," Cushman said.
The study found that the group of women with a specific genetic trait were also at increased risk for blood clots.
"The findings would suggest that if a person does have a family history of thrombosis, they might have a pre-disposing genetic trait, and those women might be appropriate for testing if they're considering taking hormones for their menopausal symptoms," Cushman said.
Researchers also found that women on hormones who took aspirin to thin their blood were still at risk for blood clots.
"There was really no evidence in the study that using aspirin regularly could be protective," Cushman said.
Doctors say women taking estrogen must be even more vigilant and report any symptoms of blood clots, which include swelling and pain.
Cushman said she's seen these findings firsthand.
"In my practice, I very commonly will see middle-aged women who are struggling with menopausal symptoms and have been prescribed hormone replacement therapy and subsequently experience a blood clot," she said.
That's what happened to Berry, so she made some changes.
"I have not gone back on the hormones. I have lost about 30 pounds, and I feel much better," Berry said.