Estrogen in menopausal hormone therapy could protect women over 50 from painful urinary infections, says study
A treatment used to relieve menopausal symptoms might protect postmenopausal women from painful urinary infections, according to a new study. Estrogen present in the hormone therapy could be keeping trouble-causing bacteria in check by boosting the growth of good ones, researchers suspect.
Urine hosts microbes, including bacteria, viruses and fungi. Healthy women in the study tended to have a diverse mix of bacteria, especially Lactobacillus. Women with fewer types of bacteria, on the other hand, experienced recurrent urinary tract infections (UTI). "We see more and more evidence that diversity in the microbiome prevents infections," Professor Florian Wagenlehner, a urologist expert who was not involved in the study, said.
The urinary tract infection is usually caused by bacteria, although fungi and viruses are also known to be responsible in some cases. It causes pain in the upper back and sides, chills, fever, nausea, and vomiting. According to researchers, around 50% to 60% of women will have urinary infection during their lifetime. But it takes a disproportionate toll on postmenopausal women.
Women going through menopause see a decline in estrogen levels. Hence, doctors prescribe Menopausal Hormone Therapy (MHT) to replace the lost hormone. However, it is important to remember that the treatment is associated with health risks such as breast cancer, stroke, attack and dementia.
In this study, Dr Nicole J De Nisco from the University of Texas at Dallas and her colleagues recruited 75 postmenopausal women who were attending the Urology Clinic at UT Southwestern Medical Center in Dallas, Texas. They collected urine samples from the participants to study the prevalence of different kinds of bacteria. They divided the participants into three groups. The first one involved healthy women with no history of UTI, the second included those with recurrent infections in the past, while the third group listed women with UTI at the time of the study.
The team identified bacteria through DNA testing. The first group of healthy women had a ten times greater variety of bacteria than those with frequent urinary infections. "Secondly, 34 of the women were taking Menopausal Hormone Therapy, and they tended to have more Lactobacillus-type bacteria in their urine, which may imply that the estrogen supports the growth of Lactobacillus in the urogenital tract. We also found that women who were taking MHT via patches or orally had more Lactobacillus than women taking MHT via vaginal cream," De Nisco explained.
Studies suggest lactobacillus protects against infections in the vagina. The team now suspects that the bacteria might be doing the same in the urinary tract as well. However, the study has only found a link between estrogen, lactobacillus and reduced UTI. Researchers are yet to prove that link.
The study opens up the possibility of treating UTI by modifying the bacterial content in the urine. If scientists can prove that estrogen boosts lactobacillus growth in the future, it will pave the way for treatments such as probiotic vaginal pessaries or estrogen therapy for vulnerable women. Vaginal pessaries are devices that are inserted into the vagina.
"We know that estrogen therapy is not recommended for all women going through menopause, and the optimal formulations of probiotic pessaries need to be developed, and their use in women with UTI would need to be tested. This is the next step in our research," De Nisco added. The study suffers from a few limitations, including that it involved only a few women. Data suggests that menopausal therapy may make people prone to other health disorders. And studies evaluating vaginal probiotics have not provided enough evidence on their safety, according to experts.
The study is presented at the European Association of Urology Virtual Congress.