Association of adjuvant aromatase inhibitor with cataract risk in postmenopausal women with breast cancer

Background: Aromatase inhibitor (AI) is a cornerstone drug for endocrine therapy of postmenopausal hormone receptor-positive breast cancer. The relationship between AI medication and subsequent cataract risk is yet inconclusive. Methods: A total of 1,697 postmenopausal, early-staged, and hormone receptor-positive breast cancer patients from the prospectively-maintained database of the Breast Surgery Department at Fudan University Shanghai Cancer Center were included, with 542 patients received no endocrine therapy and 1,155 treated with AI only. We explored the influence the use of AI or not and the duration of AI on the subsequent incidence of cataract. Results: A total of 146 (8.6%) cataracts were observed in the whole study population. The incidence of cataract is highly related to age, with incidence of cataract in patients <50 years old, 50-60 years, ≥60 years was 2.9%, 6.9%, and 13.3%, respectively (P<0.001). There was no significant relationship between adjuvant AI use and cataract (7.4% in no endocrine group vs. 9.2% in the AI group) with an adjusted hazard ratio of 1.20 (95% confidence interval: 0.8-1.7, P=0.30). The incidence of cataract in patients with long-term AI (more than 5 years) could be high up to 14.7%, but without statistical significance compared to those the shorter duration (P=0.52). Conclusions: There is no significant association between use of AI and cataract in postmenopausal breast cancer patients. Of note, age is an important risk factor for cataract and it is necessary to surveil the eye health in postmenopausal elderly women.