WASHINGTON -- Current use of menopausal hormone therapy (MHT) was associated with an approximately 50% increased risk of major lower gastrointestinal bleeding, researchers said here.
Users of MHT had no difference in risk of upper GI bleeding but were nearly three times more likely to have ischemic colitis, , a medical student at SUNY Downstate College of Medicine in New York City and researcher at Massachusetts General Hospital (MGH) in Boston, and colleagues reported.
Action Points
- Note that this study was published as an abstract and presented at a conference. These data and conclusions should be considered to be preliminary until published in a peer-reviewed journal.
Longer duration of MHT use also was associated with an increased risk of developing ischemic colitis, they stated in a presentation at the Digestive Disease Week annual meeting.
Though hormone therapy is an effective treatment for menopause, clinicians should be cautious about using it in patients with a history of ischemic colitis, co-author , of MGH, told ֱ.
"There is an increased risk, no question about it," Singh said. "It's a low risk, but it's a real risk."
The actual risk of bleeding is still very low, cautioned , DDW conference chair and gastroenterologist at the University of Michigan in Ann Arbor. During 8 years of follow-up, only 973 cases in 211,344 patients had confirmed cases of major GI bleeding.
Estrogen and progesterone are known to produce a prothrombotic state, which could increase the tendency to form a thrombus in the blood vessels supplying the large intestine, Singh postulated. This leads to the necrosis and sloughing of mucosa that characterize ischemic colitis.
Though there are reported cases of GI bleeding of patients on MHT, this is the first prospective study looking at the phenomenon, Singh said.
The observational study looked at 211,344 women, ages 24 to 55, who were enrolled in the Nurses' Health Study in 1976 and the Nurses' Health Study II in 1989 and followed through 2012.
From 2006 through 2012, participants in the study filled out biannual questionnaires that reported prior episodes of major GI bleeding that required hospitalization or a blood transfusion. Self-reports were confirmed by a medical record review.
Results were adjusted for age, age of menopause, menopause type, parity, body mass index, smoking status, history of oral contraceptive use, and use of aspirin and nonsteroidal anti-inflammatory drugs.
Researchers did not adjust for other anticoagulants, such as clopidogrel or coumadin. An additional limitation was lack of data on type and route of MHT, Singh said.
There were 973 confirmed cases of major GI bleeding among women after menopause (504 upper GI cases and 469 lower GI cases).
Current users of MHT had a significantly higher risk of overall GI bleeding compared with non-users (hazard ratio 1.2, P=0.047 for trend).
They also had a significantly increased risk of lower GI bleeding (HR 1.5, P=0.014 for trend), largely due to ischemic colitis (HR 2.8, P=0.002 for trend).
Increasing duration of MHT use was linearly associated with an increased risk of ischemic colitis (P=0.001 for trend):
- Duration of 1-5 years: HR 1.7
- Duration of 6-10 years: HR 2.3
- Duration of ≥11 years: HR 2.6
In addition to knowing what the risks are before initiating therapy, patients on MHT should ask their doctors at regular intervals if they should still be on the drug, Singh stated.
Disclosures
The study was funded by the National Institute of Diabetes and Digestive and Kidney Diseases.
Primary Source
Digestive Disease Week
Source Reference: Boylan MR, et al "Menopausal hormone therapy is associated with increased risk of lower gastrointestinal bleeding" DDW 2015; Abstract 783.