Type 1 diabetes in itself is an autoimmune disease and it involves a slightly higher risk of another autoimmune diseases. Vice versa, a person with another autoimmune disease has a slightly higher risk of getting type 1 diabetes at a later stage.
Common autoimmune diseases include coeliac disease, thyroid diseases, Addison’s disease where the adrenal glands do not produce enough cortisol, pernicious anaemia and vitiligo.