Endometriosis increases the risk of Type 2 diabetes

Endometriosis can increase the risk of Type 2 diabetes, according to research done by George Mason College of Public Health. The association was strongest among premenopausal women and women without obesity, groups not traditionally considered at the highest risk for Type 2 diabetes, according to the research, which was published in August in Diabetologia.

Endometriosis is a chronic inflammatory condition that develops when endometrial tissues grow outside of the uterus. Endometriosis can be found on the ovaries, fallopian tubes and outer surface of the uterus. The most common symptom is pain; other symptoms include bleeding or spotting, infertility and digestive issues. It affects more than 11% of American women between 15 and 44. It is especially common among women in their 30s and 40s, according to the U.S. Health and Human Services.

“Previous studies largely evaluated endometriosis as a single condition and generally reported little or no overall association with Type 2 diabetes,” Maggie Fuzak Nunziato, Ph.D., the study's lead author and a Ph.D. candidate in epidemiology at George Mason, said in a news release. “Our findings add to a growing understanding that endometriosis may affect more than reproductive health alone.”

Fuzak Nunziato and her colleagues analyzed electronic health records of almost 3 million women who lived in Utah between 1996 and 2021. They used the Utah Population Database (UPDB), which includes data for more than 11 million people. Researchers identified almost 100,000 women who received an endometriosis diagnosis during the study period.

Researchers found that women with endometriosis had an overall 46% higher risk of developing Type 2 diabetes, with risk varying across different forms of endometriosis. The risk was highest among women with extra-pelvic endometriosis, meaning the disease is found outside the pelvis.

There also was a strong association among women with body mass indexes lower than 30 kg/m2, meaning women with underweight, healthy weight, or overweight but not obese. These women have generally not been considered at risk for diabetes. “Our findings add to a growing understanding that endometriosis may affect more than reproductive health alone,” Fuzak Nunziato said.

Researchers said they believe the chronic inflammation associated with endometriosis may play a role in metabolic health. “These findings may have implications for future research on metabolic risk assessment among individuals with endometriosis and support the need for further investigation into the biological mechanisms linking reproductive and metabolic health,” researchers wrote.

Researchers said there are several limitations to their research. The first is that patients were identified based on ICD codes, and they may be subject to misclassification. Women with endometriosis are more likely to see healthcare providers more often, increasing the likelihood of detection of diabetes. Additionally, factors that could affect metabolic outcomes, such as diet, physical activity and use of hormone treatments, were not measured in this analysis.