Strabismus and Strabismus Surgery in the U.S. Veterans Health Administration: Foundational Analyses of Electronic Health Record Data from 2000 to 2022.

Background/

Objectives

Strabismus, or eye misalignment, has not been well-described in U.S. military Veterans. This study was undertaken to characterize Veterans with a strabismus diagnosis as well as those who underwent strabismus surgery.

Methods

A retrospective analysis of electronic health records (EHR) from the Veterans Health Administration (VHA) was conducted using patient data from 2000 to 2022. VHA-enrolled Veterans ≥ 18 years with strabismus-related International Classification of Diseases (ICD) codes and/or Current Procedural Terminology (CPT) codes were identified. Total and demographic (age group, sex, race, and ethnicity) stratified prevalence and incidence rates were calculated, as well as sex-stratified residual lifetime risk.

Results

A total of 321,639 patients had a strabismus diagnosis, with most (320,107) identified by ICD code (CPT code only = 1532). The peak prevalence was 2.29% in the 2022 VHA fiscal year (1 October 2021 to 30 September 2022) with a median annual age-adjusted incidence rate of 168.9/100 000 enrollees. Age-adjusted lifetime risk was 10.19% for males and 11.03% for females. Significant differences by age group, sex, race, and ethnicity were identified for strabismus prevalence (p < 0.001), strabismus diagnosis types (p < 0.001), and between patients with strabismus who either did or did not have surgery (sex p < 0.05, all others p < 0.001). Compared with other U.S. adult populations, VHA Veterans have similar or higher prevalence, annual incidence rates, and lifetime risk of a strabismus diagnosis, with demographic factors significantly affecting the rates and types of strabismus. Notably, despite lower prevalence and incidence than other racial groups, a higher percentage of African American patients with strabismus underwent surgery, contrasting with published Medicare data. Inconsistencies between ICD and CPT codes highlight potential miscoding and/or missing codes, with reliance on ICD code diagnoses potentially underestimating strabismus prevalence.

Conclusions

Further characterization of factors affecting strabismus risk among these patients may help improve strabismus diagnosis and management for many US Veterans. This foundational study serves as a platform for detailed predictive analyses in determining risk outcomes for individuals. This includes better identification of at-risk individuals, informing effective resource allocation for treatment.