Danish study links oral menopausal hormone therapy to clot risk

A Danish study published in The BMJ linked oral menopausal hormone therapy to higher risk of venous thromboembolism (VTE), with risks varying by dose and duration. Researchers analyzed data on 1,060,082 women aged 50 to 69 in Denmark from 2003 to 2021. The study recorded 9,807 VTE cases, 18,460 ischemic strokes and 11,974 heart attacks, according to Healio.

Women using oral hormone therapy had higher VTE risk than nonusers (HR = 1.6). Healio reported that more than 1 mg of oral estradiol per day was linked to higher VTE risk than 1 mg or less (HR = 1.3), and to higher risks of stroke (HR = 1.5) and heart attack (HR = 1.4) than no hormone therapy. Healio said transdermal therapy was not linked to the three outcomes. MedPage Today reported an exception: higher heart attack risk with combined cyclic transdermal therapy. The observational study cannot establish cause and effect, MedPage Today reported.