Research has shown that women with premature ovarian failure, the cessation of menstruation before the age of 40, are at significantly higher risk of developing serious autoimmune diseases.
Premature ovarian insufficiency (POI) occurs when the ovaries stop functioning properly and are unable to produce eggs in women under the age of 40. Menstrual periods become irregular and then stop, and some women experience symptoms of menopause. It affects 1% of women worldwide.
Studies have shown that women with POI are two to three times more likely to develop serious autoimmune diseases, including type 1 diabetes, hyperthyroidism, lupus, and inflammatory bowel disease, compared to the general population.
The researchers say their findings significantly strengthen the hypothesis that autoimmune processes play a “pivotal role” in the development of POI.
The study, published in the journal Human Reproduction, is the largest to investigate the link between autoimmune disease and POI.
Finnish researchers followed nearly 20,000 women for at least 12 years. They analyzed health data from a comprehensive Finnish registry and identified nearly 4,000 women under the age of 40 who were diagnosed with POI between 1988 and 2017.
They matched each with four women of the same age, and looked at how many of them developed a severe autoimmune disease between 1970 and 2017. They found that 5.6% of women with POI had been diagnosed with at least one autoimmune disease before their diagnosis, and 12.7% were diagnosed with an autoimmune disease after their POI diagnosis.
Overall, women were 2.6 times more likely to have developed an autoimmune disease before POI diagnosis compared with controls. These risks ranged from almost two times higher for hyperthyroidism and rheumatoid arthritis to almost 26 times higher for polyglandular autoimmune disease.
Women who developed POI but had no history of autoimmune disease were almost three times more likely to be diagnosed with an autoimmune disease over the next three years.
The authors note that these associations are likely underestimated because the study only included autoimmune diseases diagnosed at specialized medical centers. Less severe diseases, such as celiac disease and hypothyroidism, are often diagnosed and treated in primary care, so the overall prevalence of autoimmune diseases in women with POI is likely higher.
“It is important to emphasize that most women with POI will not develop severe autoimmune diseases, and most women with severe autoimmune diseases will not develop POI. However, health professionals need to be aware of the increased risk, and they should inform their patients about it,” said Dr Susanna Savkoski, an obstetrician-gynaecologist at Oulu University Hospital and University of Oulu in Finland, who led the study.
Because POI threatens fertility, women at high risk for the disease should consider trying to conceive at a young age, she says, although some autoimmune diseases should be taken into consideration as they can significantly increase the risk of pregnancy complications.
The authors hope to study the biological mechanisms of POI and autoimmune diseases to help develop preventative treatments. “We are investigating whether long-term use[of hormone replacement therapy]can prevent other diseases that occur in women with POI,” Savkoski said.
Responding to the findings, Louise Kenny, professor of maternal and fetal health at the University of Liverpool, said: “POI is poorly understood and devastating – it limits young women’s chances of conceiving their own biological child and increases their risk of menopause-related complications such as osteoporosis.”
New studies are needed to confirm the immune system’s role, she added.
Bassell Watter, associate professor of reproductive medicine at Anglia Ruskin University, said the study highlighted the need for comprehensive, multidisciplinary care for women with POI because they are at increased risk of long-term health complications.
He added: “This study does not help us understand the causation of POI, so it remains to be seen whether it is the result of an autoimmune disease or whether a lack of ovarian activity may exacerbate the autoimmune response in affected women.”
