Why Lupus Is More Common Among Women

Lupus is an autoimmune disease that affects more than 1.5 million people in the United States, according to the Lupus Foundation of America. People with lupus often feel symptoms such as pain, fatigue, or cognitive issues because the immune system attacks the healthy cells of the body. Although lupus can affect anywhere in the body, more often it affects the skin, joints, and internal organs.

While anyone can get lupus, 90% of people with lupus are women. Because lupus is often diagnosed during a woman's reproductive years, researchers are looking into how hormones might play a role in why lupus develops more prevalently in women, according to the University of Washington Medicine. A 2014 review in Nature Reviews Rheumatology suggested that estrogen affects certain important parts of the immune system. On the other hand, progesterone counteracts the effects of estrogen on some of these immune system pathways. This suggests that the balance between estrogen and progesterone in the body can determine whether or not lupus develops.

The prevalence of women developing lupus might also have to do with the extra X chromosome. A 2018 study in Science Immunology found that even though the spare X chromosome becomes inactive in cell activity, it still makes the protein TLR7. This protein typically identifies threats in the immune system. However, this excess of TLR7 could possibly trigger autoimmune problems such as lupus (via Stat News).

The University of Washington says that 70% of the risk of lupus might lie in your genes. Even if no one in your family has had lupus, it's possible that a family member might have had a similar autoimmune disease. Other factors can determine whether or not the genes associated with lupus activate the disease. However, the Lupus Foundation says that 20% of those with lupus may also have a parent or sibling with lupus. Lupus develops in 5% of children whose parents have lupus.

Race and ethnicity also factor into the likelihood of developing lupus, according to the University of Washington. Black, Hispanic, and Asian women are more affected by lupus than white women. They are also more likely to have complications from the disease such as kidney disease or organ complications. Rheumatologists tell WebMD that they're not sure why these differences exist, but genetics do have a role. Other factors such as access to rheumatologists, language and education barriers, and structural racism in health care might contribute to the higher risk.