Effects of Smoking on Outcomes of Thyroid Eye Disease Treated with Teprotumumab: A Retrospective Cohort Study

INTRODUCTION: Smoking has been demonstrated to worsen the disease process and conventional treatment outcomes of thyroid eye disease. However, the effects of smoking on outcomes of thyroid eye disease treated with the novel therapeutic teprotumumab are currently unknown. Our study compares response to teprotumumab treatment between smokers and non-smokers with thyroid eye disease. METHODS: A single-center, retrospective cohort study was conducted. Inclusion criteria were patients diagnosed with thyroid eye disease who had started or completed therapy with teprotumumab at the time of our data collection. Main outcome measures included reduction in clinical activity score, diplopia, and proptosis. RESULTS: All smokers had type 2 thyroid eye disease prior to treatment and demonstrated less improvement in diplopia, proptosis, and overall clinical activity score compared to non-smokers with thyroid eye disease. There was no significant difference between smokers and non-smokers in baseline variables (sex, thyroid stimulating hormone (TSH), thyroxine (T4), triiodothyronine (T3), number of infusions completed). Data analysis revealed a statistically significant difference in proptosis reduction between non-smokers and smokers. CONCLUSIONS: Smoking is a modifiable risk factor which portends a worse response to treatment of thyroid eye disease with teprotumumab.