Postmenopausal women who take hormone replacement therapy (HRT) were found to be at increased risk of developing irritable bowel syndrome (IBS) which persists over time and often with elevated gastrointestinal symptoms, medication utilization, and diagnostic testing.

Jacqueline Khalil, MS, DO, from Case Western Reserve University/Metro Health
in Beachwood, Ohio, presented the poster, which won a Presidential Poster Award at the American College of Gastroenterology scientific

IBS disproportionately affects women, and it is hypothesized that female sex hormones may play a substantial role in the risk, the investigators stated. This study investigated the effects of HRT on IBS and its related symptoms, medication use, and diagnostic testing in postmenopausal women.

The team conducted a population-based cohort study involving postmenopausal women aged 50 or older, with and without a prescription for HRT (estrogen and progesterone), performing 1:1 propensity score matching to adjust for age, race, ethnicity, inflammatory bowel disease, and celiac disease.

The cohort included 51,395 postmenopausal women prescribed HRT and 1,311,581 not prescribed HRT after exclusion criteria. After propensity matching, each cohort comprised 46,627 patients. Among postmenopausal women prescribed HRT, 992 developed IBS at least 30 days after being prescribed the therapy compared to 581 not prescribed HRT (OR=1.75, 95% CI [1.58-1.94]). These associations persisted in sensitivity analysis over 5 years (OR=1.88 95% CI [1.54-2.29]). 

In addition, 235 postmenopausal women prescribed HRT had a new encounter diagnosis ICD code of IBS-D, 188 with IBS-C, and 148 with mixed IBS at least 30 days after being prescribed HRT compared to those not on HRT (IBS-D: OR=1.44, 95% CI [1.18-1.76]; IBS-C: OR=2.27, 95% CI [1.76-2.95]; mixed IBS: OR=1.63, 95% CI [1.26-2.12]). Hormone therapy was also associated with increased GI symptoms, including abdominal distention (OR=1.44 95% CI [1.32-1.57]).

Patients received medications that included lubiprostone (OR=1.76 95% CI [1.32-2.35]), linaclotide (OR=1.90 95% CI [1.58-2.28]), plecanatide (OR=2.73 95% CI [1.68-4.45]), dicyclomine (OR=1.46 95% CI [1.30-1.64]), and tricyclic antidepressants (OR=1.84 95% CI [1.68-2.02]). These patients also underwent more diagnostic procedures such as colonoscopy (OR=2.08 95% CI[1.79-2.42]) and esophagogastroduodenoscopy (OR=1.21 95% CI[1.09-1.33]).

The investigators concluded that their findings emphasize the importance of considering the increased risk of IBD and gastrointestinal complications when prescribing HRT to postmenopausal women.
 

Khalil J, Sun Y, Kaelber D, Lembo AJ, Song G. P2357 - Hormone Replacement Therapy Is Associated With Increased Risk of Developing Irritable Bowel Syndrome in Post-Menopausal Women. Presented at: American College of Gastroenterology. October 28, 2024. Philadelphia, Pennsylvania.