Risk of smoking in thyroid-associated orbitopathy.

Cigarette smoking greatly increases the risk of thyroid-associated orbitopathy (TAO) (odds ratio 7.7, interval 4.3 to 13.7) and the number of cigarettes smoked per day seems to be a significant independent determinant for the incidence of proptosis and diplopia. The own prospective study showed that soft tissue involvement (ATA activity score) and ocular motility could be influenced less by steroid and irradiation treatment in smokers in comparison to nonsmokers. The mechanisms whereby smoking affects eye disease are widely unknown, cytokines (INF-gamma, TNF-alpha, IL-1), receptors and receptor antagonists have probably a crucial role.