Women whose periods stop prematurely are at greater risk of autoimmune diseases, research shows
Women with premature ovarian insufficiency, where menstruation stops before the age of 40, are at much greater risk of serious autoimmune diseases, according to research.
Premature ovarian insufficiency (POI) occurs when women under the age of 40 stop producing eggs because their ovaries are no longer functioning properly. Menstruation becomes irregular and then stops, and some women experience symptoms of menopause. It affects 1% of women worldwide.
Research has shown that women with POI are two to three times more likely to develop serious autoimmune diseases, such as type 1 diabetes, overactive thyroid, lupus, and inflammatory bowel disease, compared to the general population.
The researchers say the findings significantly strengthen the hypothesis that autoimmune processes play a “critical role” in the development of POI.
The study, published in Human Reproduction, is the largest study into the association between autoimmune diseases and POI.
Finnish academics followed almost 20,000 women for at least 12 years. They analyzed health data from Finland’s comprehensive registers and identified almost 4,000 women under 40 who had a POI diagnosis between 1988 and 2017.
Each of them was matched with four women of similar age. They then examined how many of them developed serious autoimmune diseases 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% had POI after their diagnosis.
Overall, women were 2.6 times more likely to have an autoimmune disease before a POI diagnosis compared with controls. These risks ranged from nearly double for overactive thyroid and rheumatoid arthritis to nearly 26 times for polyglandular autoimmune diseases.
Women with POI who did not have a pre-existing autoimmune disease were almost three times more likely to be diagnosed with POI in the subsequent three years.
According to the authors, these associations are likely underestimates because the study only included autoimmune diseases diagnosed in specialized health centers: less serious conditions such as celiac disease and underactive thyroid are often diagnosed and treated in primary care. As a result, the overall prevalence of autoimmune diseases is higher in women with POI.
Dr Susanna Savukoski, a gynaecologist and obstetrician at Oulu University Hospital and the University of Oulu, Finland, who led the study, said: “It is important to emphasise that most women with POI do not develop serious autoimmune diseases, and most women with serious autoimmune diseases do not develop POI. However, healthcare professionals should be aware of the increased risk, and patients should also be informed about it.”
Because POI poses a threat to fertility, women at increased risk for the condition should consider trying to conceive at a young age, she says. However, some autoimmune diseases can significantly increase the risk of complications during pregnancy and should be taken into consideration.
The authors want to study the biological mechanisms of POI and autoimmune diseases to help develop preventive treatments. Savukoski said: “We are investigating whether long-term use of (hormone replacement therapy) can prevent other conditions from developing in women with POI.”
Commenting on the findings, Louise Kenny, professor of maternal and fetal health at the University of Liverpool, said: “POI is poorly understood and devastating. It limits the opportunity for young women to carry their own biological child and increases their risk of menopausal complications such as osteoporosis.”
New research is needed to confirm the role of the immune system, she added.
Bassel Wattar, senior lecturer in reproductive medicine at Anglia Ruskin University, said the research highlights the need for multidisciplinary and holistic care for women with POI due to the increased risk of long-term health problems.
He added: “This study does not help us understand the causality of POI and therefore the question remains whether it is a consequence of autoimmune disease or whether the lack of ovarian activity may exaggerate an autoimmune response in affected women.”