The study, published in the Lancet eClinicalMedicine journal, included more than 6,600 people with autoimmune conditions. Most were female and from the UK. Women were more likely to have doctors wrongly attribute their conditions to psychiatric causes and to wait longer for a diagnosis.
Patients listed their main condition. Almost a quarter of the women had autoimmune thyroid disease, which includes underactive Hashimoto's disease and overactive Graves' disease. One in seven women had systemic lupus, which can cause tiredness, rashes and muscle pain.
Lead author Melanie Sloan, a researcher in the department of public health and primary care at Cambridge and UEA, said some women wait years for a diagnosis, which delays their treatment. She also pointed to the lasting cost. "The damage caused to women by these types of misdiagnosis can be very long lasting in terms of trusting doctors and their own self-esteem."
About one in 10 people worldwide has an autoimmune condition.