Risk-Stratified Monitoring of Open Angle Glaucoma Suspects Based on Diagnostic Conversion Risk.

OBJECTIVE

To assess annual rates and determinants of diagnostic conversion from open angle glaucoma suspects (OAGS) to primary open angle glaucoma (POAG) in the United States and develop a pragmatic, risk-stratified framework for tailoring follow-up frequency based on per-visit conversion risk.

DESIGN

Retrospective cohort study.

METHODS

Patients with newly diagnosed OAGS between 2007 and 2021 were identified in Optum's de-identified Clinformatics Data Mart Database based on International Classification of Diseases codes. Inclusion required (1) continuous enrollment during a 3-year lookback period and 5-year study period from index (first) date of OAGS diagnosis, (2) diagnosis by an ophthalmologist or optometrist with ≥1 optical coherence tomography (OCT) or visual field test, and (3) no prior glaucoma-specific treatment or POAG diagnosis. Cox proportional hazards modeling was performed to assess factors associated with diagnostic conversion to POAG. In a secondary analysis, subgroups were created based on age and treatment status and predicted probability of conversion was estimated for each group.

MAIN OUTCOME(S) AND MEASURE(S): Diagnostic conversion of POAG.

RESULTS

Among 83 305 OAGS patients (57.6% female; 5.4% Asian; 11.1% Black; 12.7% Hispanic; 70.8% non-Hispanic White), 17 134 (20.6%) converted to POAG, corresponding to an overall annual conversion rate of 6.1% (9.4% in year 1, 5.3% in years 2-5). On multivariable Cox regression, older age (HR ≥ 1.38), male sex (HR = 1.12), Black race (HR = 1.14), location outside the Northeast (HR ≥ 1.24), record of gonioscopy (HR = 1.90), and OAGS treatment (HR ≥ 1.31) were associated with greater hazard of conversion (P ≤ .02). Among the lowest-risk patients (<50 years; untreated), annual conversion was 2.0% with follow-up every 0.9 ± 0.6 years, whereas the highest-risk patients (>70 years; treated) had a 16.7% annual conversion rate with follow-up every 0.4 ± 0.4 years after year 1. When standardized to a 5.0% per-visit conversion threshold, corresponding monitoring intervals were 6.1 years and 0.6 years, respectively.

CONCLUSIONS

The rate of conversion from OAGS to POAG is <6.0% per year beyond the first year after diagnosis. Estimating per-visit conversion risk enables risk-stratified surveillance strategies that may safely reduce visit frequency for very low-risk patients while preserving timely detection in higher-risk groups, thereby improving clinical efficiency and resource allocation.