Graves' disease, endocrine ophthalmopathy and smoking

We have evaluated the association between smoking, Graves' disease and endocrine ophthalmopathy in a case-control study of 208 patients with newly diagnosed Graves' disease and carried out a retrospective survey of 72 patients treated for Graves' disease and admitted to our ward because of endocrine ophthalmopathy. In the prospective study, patients with Graves' disease smoked significantly more than their healthy controls (41% vs 30%, p < 0.01 for current smokers, odds ratio 1.6, 95% confidence interval 1.1-2.3, and p < 0.05 for patients with a history of smoking, odds ratio: 1.4, 95% confidence interval 1.0-1.9). Among the patients with endocrine ophthalmopathy at diagnosis, there were slightly more patients with a history of smoking (p < 0.05, odds ratio 2.1, 95% confidence interval 1.1-3.9), but not more current smokers when compared with the remaining group. The patients with eye problems tended to have a more active disease with higher levels of thyroxine and TSH-receptor antibodies, but no difference was seen in thyrogastric autoantibodies. No effect of smoking on thyroid hormone and autoantibody levels could be detected. In the retrospective survey we found 64%, 71% and 87% smokers among patients with moderate, severe and malignant eye disease, respectively. In summary, the results show that smoking is associated with an increased risk of contracting Graves' disease and that it enhances the severity of the eye disease in cases that develop endocrine ophthalmopathy during the course of treatment.