Hormone Replacement Therapy: Do the Risks Outweigh the Benefits?

A review of studies suggests long-term hormone replacement therapy increases risk of cancer, cardiovascular problems, and other serious conditions.

Although hormone replacement therapy (HRT) can decrease the risk of developing fractures, it increases the risk of developing certain cancers, thromboembolic events, and urinary incontinence, according to a review published online on May 29, 2012, in the Annals of Internal Medicine. The review was carried out to help update guidelines from the United States Preventive Services Task Force (USPSTF).

The authors of the review looked at studies of 2 types of HRT therapy—estrogen-plus-progestin therapy and estrogen-only therapy—published since the release of the USPSTF’s initial recommendations in 2002. Prior to 2002, HRT was used to prevent chronic conditions, including cardiovascular disease, dementia, and osteoporosis. However, as a result of trials associating HRT with adverse effects, the therapy is currently indicated only for prevention of osteoporosis and for short-term treatment of menopausal symptoms.

The authors reviewed 51 articles from 9 trials that compared HRT therapy to placebo and focused on 2 Women’s Health Initiative trials including participants who were generally between the ages of 60 and 69.

The authors report that the benefits of HRT include fewer fractures and fewer cases of diabetes, but also that HRT is associated with higher risks of certain conditions. Patients who received either kind of HRT had more cases of stroke, gallbladder disease, and urinary incontinence. Those who received estrogen-plus-progestin also had more cases of invasive breast cancer, deep venous thrombosis, pulmonary embolism, probable dementia, and death from lung cancer. (However, incidence of invasive breast cancer was reduced in patients undergoing estrogen-only HRT.)

HRT patients also had more abnormal mammography results, larger tumors, and more advanced stages of breast cancer. Other cancers, such as lung, endometrial, ovarian, and cervical cancers, were not increased during the estrogen-plus-progestin trial, although the incidence of death due to lung cancer was increased in those taking estrogen plus progestin.

Trial limitations included low medication adherence, high attrition, inability to detect risks for certain conditions, and the small number of studies available for evaluation.

The updated finding confirmed the USPSTF’s earlier position, leading the researchers to recommend HRT for short-term therapy only, lead researcher Heidi Nelson told HealthDay.