Discordant results have been reported in the literature about the association of thyroid disorders and other systemic, or organ specific, autoimmune diseases. We have carried out a prospective study investigating about the correlation between Graves’ disease (GD) and other autoimmune diseases from data obtained by the literature.
The study involved 3209 GD patients [984 of whom with Graves’ ophthalmopathy (GO)], in comparison to: 1) 1069 healthy controls; 2) 1069 with multinodular goiter; 3) 1069 patients with autoimmune thyroiditis (AT). All the subjects were matched by age and gender, had a similar iodine intake and came from the same area.
GD patients showed a significant increase of the prevalence of certain autoimmune disorders, compared to controls. The mostly detected associations were: vitiligo (2.6%), chronic autoimmune gastritis (2.4%), rheumatoid arthritis (1.9%), polymyalgia rheumatica (1.3%), multiple sclerosis (0.3%), celiac disease (1.1%), type 1 diabetes (0.9%), systemic lupus erythematosus and sarcoidosis (<0.1%), Sjögren disease (0.8%). Moreover, three associated autoimmune disorders were found in 1.5% patients with GD. GO patients showed higher (18.9%) prevalence of autoimmmune disorders, with respect to GD patients not having GO (15.6%). The pattern of the associated autoimmune disorders in GD was quite similar to that observed in AT patients.
These researches shed light on the importance of screening GD patients, who are sick, or who develop new unspecific symptoms (also if in treatment for the hyperthyroidism), for the presence of other autoimmune disorders.