Effect of age on reoperation rate in children undergoing exotropia surgery

Purpose To determine the effect of age on the reoperation rate in children undergoing exotropia surgery. Methods This was a population-based retrospective cohort study using claims data that included children <= 12 years who had undergone exotropia surgery as the first strabismus operation and had >= 3 years of continuous enrolment were selected from the Optum de-identified Clinformatics Data Mart Database (2003-2019). Patient age at the first exotropia surgery was grouped into three categories; 0-3, 4-6, and 7-12 years. We assessed the sex, race, age, surgical methods, continuous enrolment period after the first surgery, and the time between the first surgery and reoperation. Cox regression analysis was used to estimate the risk of reoperation at different ages. The hazard ratio of reoperation in children undergoing exotropia surgery according to the age at the first exotropia surgery. Results Among 2015 children, 312 (15.5%) underwent one or more reoperations. A reoperation was more often performed for recurrent exotropia (n = 231) than for consecutive esotropia (n = 81). The time between the first surgery and reoperation was shorter for reoperation for consecutive esotropia (376 days) than for recurrent exotropia (672 days) (p < 0.001). Younger children showed a higher reoperation hazard ratio than older children (p < 0.001). In reoperation for consecutive esotropia, the patients aged 0-3 years showed a high hazard ratio (2.82; 95% CI, 1.59-5.01). Conclusion Children undergoing exotropia surgery at a younger age have a higher reoperation rate than those undergoing surgery at an older age.