Why are women more predisposed to autoimmune conditions?

 Since the age of 17, I have been curious about autoimmune conditions. I had experienced drug lupus in the past. I was told that it was due to my acne medication at the time; however, I always wondered if maybe there was a correlation to my biological sex. Furthermore, in medical school we were told that women were more predisposed to autoimmune diseases. But why? Why did having two XX chromosomes make you a risk factor for conditions like RA or Lupus?

 Well.. did you know that researchers have speculated a correlation with having two XX chromosomes and autoimmune diseases? There are genes on one X that can initiate an autoimmune reaction, and females happen to have two of those. They are essentially getting a double dose of that specific gene. Since males have X and Y, they do not get that double exposure from the X chromosome. Furthermore, Females go through something called X inactivation. One of their X chromosomes will be inactivated in a cell causing the other one to be predominant. The X that is inactivated can now be seen as foreign to the body and provide itself as an antigen. When this happens, the body can form an immune response and hence a possible autoimmune disease. In fact, the process I just described is suggested to a potential cause for Lupus

 There are other possible causes for Lupus. I will describe one more. It is suggested that there are genes expressed on one X chromosome, CD40LG and CXCR3, that become overexpressed when one of those X’s fails to inactivate. There are still studies being done to further assess this theory. It is speculated that proper X inactivation may help decrease disease progression.

 It is also suggested that hormonal changes can exacerbate an autoimmune disease. Hormonal changes may not be the cause of a skin condition like Psoriasis; however, it is speculated that hormonal changes can make the skin more sensitive. The endocrine system and skin are closely linked, and an imbalance could increase the severity of Psoriasis.

 In addition, Rheumatoid arthritis and Sjogren’s syndrome are thought to be linked to hormonal changes as well. With RA, there are issues with the bones and joints. It is suggested that around menopause, a decrease in estrogen and progesterone can decrease protection of the bone and joints making RA more severe. Sjogren’s Syndome is also thought to be linked to a decrease in estrogen.

Now that hormones are thought to be a link, pregnancy and puberty are a concern. These are times where hormonal imbalances occur. With pregnancy, those changes can last until at least one year post pregnancy. It is also thought that a mother carry a baby could face a decreased immune system making autoimmune issues more likely. As far as puberty goes… a study done in Taiwan observed an increase in juvenile SLE in girls compared to boys. It is also suggested that there is an increase of multiple sclerosis for girls after the onset of puberty.

I’ve learned something new today, and I appreciate the review article on the prevalence of autoimmune disorders in women that was published in the Cureus Journal of Medical Science in May 2020.

 Sabrina Billings MS4

Drexel University College of Medicine

 

 

 

Angum F, Khan T, Kaler J, Siddiqui L, Hussain A. The Prevalence of Autoimmune Disorders in Women: A Narrative Review. Cureus. 2020;12(5):e8094. Published 2020 May 13. doi:10.7759/cureus.8094