Estrogen therapy could be dangerous for women with existing heart risk

The research also showed that in women without existing atherosclerosis, hormone therapy use included some positive effects on lipids but also some negative effects related to heart health, said MaryFran Sowers, lead researcher and professor of epidemiology at the University of Michigan School of Public Health.

The U-M study came about, Sowers said, in trying to explain what's behind the so-called timing hypothesis. The timing hypothesis suggests that if a woman implements a hormone therapy program within six years of her final menstrual period, this narrow window is enough to deter heart disease from developing with the onset of menopause. But the U-M findings suggest that explanation isn't quite so simple, Sowers said.

Even within the six-year window, there were negative aspects related to heart disease. While the positive outcomes on HDL and LDL cholesterol levels were observed, Sowers said, researchers also saw negative outcomes in terms of the inflammation process—which can be related to heart disease.

Sowers said the research shows it's critical for women considering hormone therapy to discuss their heart health with their doctor.

"If the woman walks into the doctor's office with a certain degree of (heart disease) burden already, then she and her health care provider may decide that hormone therapy adds too much to the burden," Sowers said. "If she doesn't have that burden, they may decide that hormone therapy is an acceptable burden.

"The woman should say to her health care provider, 'What kind of information do we need to gather in order to make an informed decision about whether or not hormone therapy should be pursued,'" Sowers said. '"I understand there could be some heart disease risk, but that the risk may be based upon where I am now, and can you tell me where that is?'"

Heart disease risk can be measured through lipid panels, which are standard, but also by measuring inflammation markers, Sowers said. Tests for inflammation markers exist but their measurement isn't standard when a women is considering hormone therapy, Sowers said.

Hormone therapy has been controversial for years, and there was a time when there was an almost knee jerk reaction against it, Sowers said. This backlash occurred after the findings from the Women's Health Initiative study showed that some women on estrogen therapy had increased heart disease risk. The six-year timing hypothesis was an attempt to explain the findings in the WHI study, Sowers said.

Provided by University of Michigan