Previous studies have found an increased risk of gallbladder disease with the use of hormone replacement therapy (HRT) by postmenopausal women. HRT may be delivered through oral medications or through a transdermal patch. With the pill, the hormone is metabolized by the liver, but hormones delivered through the patch avoid this process. Because the liver and gallbladder work together closely, this is thought to be a pathway for the hormone effect on gallbladder disease.

Researchers from the Epidemiology Unit of the University of Oxford in England set out to determine if hormone replacement via patch would decrease the risk of gallbladder disease compared to pill form. The study published in the British Medical Journal , found that HRT may in fact increase the chance of gallbladder disease, and the pill form had a higher risk than the patch.

About the Study

The prospective cohort study gathered information from a large study of women called the Million Women Study . The study has followed over one million postmenopausal women in England since 1996 and tracked health information such as disease development and treatments. Over 6.1 years, 19,889 women were admitted for gallbladder disease. Compared to women that have never taken HRT, the risk of gallbladder disease was:

  • 1.64 times greater in women with any HRT
  • 1.68 times greater in women taking oral therapy
  • 1.17 times greater in women using patch therapy

The study also found that risk decreased as time passed after stopping HRT. The researchers concluded that for every 125 women, there would be one fewer admission for gallbladder disease with the use of the patch.

A cohort study is not considered the most reliable type of study design. Due to the study design, results may be affected by outside factors and influences that could not be controlled. It is important to look for trends and relationships in future studies by more rigorous study protocols, such as randomized, controlled studies.

How Does This Affect You?

Gallbladder disease is a common medical problem in middle-aged women. HRT appears to exacerbate the chance of developing the disease. If you do receive HRT, the patch may decrease your chance of gallbladder problems. HRT is often given in short-term doses and the risk of gallbladder disease is shown to decrease the longer one is away from HRT. Talk to your doctor about risks and benefits associated with HRT.

Talk to your doctor about risks and benefits associated with HRT.