Risk factors for Graves' Orbitopathy in surgical patients-Results of a 10-year retrospective study with review of the literature.

Introduction: We investigated known (eg age, smoking, thyrotropin receptor autoantibody (TRAb)) and new risk factors (eg thyroid peroxidase autoantibodies (TPO-Ab), thyroid size, or BMI) for Graves' disease (GD) and Graves' orbitopathy (GO), especially in combination with each other, to determine which factors play the most important role in the development of GO.

Methods: From 2008 to 2018,  = 500 patients with GD were included in this retrospective single-centre case-control study.  = 231 (46%) had a GO and  = 269 (54%) showed no GO. Differences in risk factors were determined by Mann-Whitney U and chi-square test. Combined influences of factors were examined by multivariable logistic regression.

Results: Age at first diagnosis of GD (OR = 1.043,  < .006), smoking status (OR = 2.64,  < .026) and TRAb (OR = 1.046,  < .01) had a significant impact on GO. The factors gender, TPO-Ab titre, BMI, TSH titre, T3 and T4 were not significant.

Conclusion: As it has been shown in univariate analyses, smoking, age and TRAb levels have a negative impact on the onset and course of GD and GO. Via multivariable regression, we could additionally show that smoking is the most important factor out of those analysed. TRAb might be a helpful surrogate parameter in the assessment of the progress of GO and therefore might be one factor in the decision-making process for potential early operative surgery. With regard to the hitherto unclear role of BMI, thyroid size and TPO-Ab in the course of GO, this study could not find any clinically relevant influence.