Relationship between cigarette smoking and Graves’ ophthalmopathy

Environmental triggers in the development of Graves’ disease (GD) have been suggested from the very first description of the disease. Since 1987 a number of studies from various countries, have assessed the risk for Graves’ ophthalmopathy (GO) associated with smoking, and found an odds-ratio of approximately 4 associated with smoking. Smokers have a higher risk for more advanced GO and a dose response relation is evident. Temporality is suggested by a few prospective studies, as is reversibility since former smokers had a lower risk of developing GO than current smokers, even with a comparable lifetime tobacco consumption. In view of the biological plausibility of the association (suggested mechanisms include tissue hypoxia, modulation of circulating pro- and anti-inflammatory cytokines and accentuation of fibroblast HLA-DR expression) it seems that the association is, indeed, causal. Treatment effect of GD/GO is also influenced by cigarette smoking. It is an independent risk factor for relapse of GD after antithyroid drug treatment. Furthermore, it attenuates the effect of orbital radiotherapy and high-dose systemic glucocorticoids in GO and causes a higher rate of progression of eye disease after radioiodine therapy.