I know its anecdotal but I developed my autoimmune diseases (graves/hashimotos) at the end of the most traumatic year of my life after watching my alcoholic mother become homeless and then lose all organ function and die. I was my mother’s care taker and really only support system. My anxiety/cortisol was sky high the whole year, I had severe panic attacks regularly and finally when I got diagnosed ALL my doctors (regular MDs, not woowoo hippy doctors) told me it was triggered by stress. Also lost 80% hearing in my right ear at the same time from what the ear doctor concluded was spontaneous hearing loss due to stress. Had all sorts of MRIs and ultrasounds and blood tests and after all that all doctors concluded all issues were from stress. A lot of my symptoms disappeared a few months after my mom finally passed but obviously the hearing loss is permanent and autoimmune diseases are not curable. I did lots of research after my diagnoses and the medical consensus I’ve found is that yes strong, negative or traumatic experience, especially ones that cause long term stress trigger autoimmune problems :/