Epidemiology and prevention of Graves' ophthalmopathy.

Graves' ophthalmopathy is clinically relevant in approximately 50% of patients with Graves' disease, severe forms affecting 3%-5% of patients. Two age peaks of incidence are observed in the fifth and seventh decades of life, with slight differences between women and men. The disease is more frequent in women than in men, although the female-to-male ratio is only 1:4 in severe forms of eye disease. The natural history of Graves' ophthalmopathy is incompletely defined, but in many instances, especially in mild forms, the disease may remit or improve spontaneously. The onset of the ophthalmopathy is in most cases concomitant with the onset of hyperthyroidism, but eye disease may precede or follow hyperthyroidism. Cigarette smoking plays an important role in the occurrence of the ophthalmopathy, and is also associated with a higher degree of disease severity and a lower effectiveness of its medical treatment. Primary prevention (i.e., avoidance of the occurrence of the ophthalmopathy) is presently not feasible, but smoking withdrawal in relatives of patients with Graves' disease might be important. In terms of secondary prevention (i.e., avoidance of progression of subclinical eye disease into overt and severe ophthalmopathy) in addition to refraining from smoking, early and accurate control of thyroid dysfunction (both hyperthyroidism and hypothyroidism), as well as early diagnosis and treatment of mild eye disease are important. As to the role that management of hyperthyroidism may play in the course of Graves' ophthalmopathy, while antithyroid drugs and thyroidectomy are not disease-modifying treatments, radioiodine therapy causes a progression of the ophthalmopathy in approximately 15% of patients, especially high-risk patients, who smoke, have severe hyperthyroidism or uncontrolled hypothyroidism, high levels of thyrotropin (TSH)-receptor antibody, or preexisting eye disease. However, the risk of radioiodine-associated progression of the opthalmopathy can be eliminated by concomitant treatment with middle-dose glucocorticoids. In terms of tertiary prevention (i.e., avoidance of deterioration and complications of overt disease) early immunosuppressive treatment or orbital decompression, as appropriate, are essential tools. Smoking withdrawal may increase the effectiveness of immunosuppressive treatment.