Risk factor stratification in early-onset primary angle closure disease.

PURPOSE: To identify the potential biometric associations in patients with early-onset primary angle closure disease (EOPACD), and the relevant biometric cut-offs for distinguishing them.

DESIGN

A prospective cross-sectional observational study.

PARTICIPANTS

The study included 190 eyes with EOPACD of 128 patients, aged 20-40 years (mean age 34.2 ± 6.0 years).

METHODS

EOPACD (defined as primary angle closure presenting before 40 years of age) was classified into early-onset primary angle closure suspect (EOPACS), early-onset primary angle closure (EOPAC), and early-onset primary angle closure glaucoma (EOPACG) groups. The participants underwent a baseline clinical examination, including gonioscopy, ultrasound biomicroscopy, anterior segment ocular coherent tomography (ASOCT) and optical biometry (IOL Master). Statistical analysis was performed to identify risk factors associated with EOPACG such as axial length (AL), lens thickness (LT), lens vault (LV), anterior chamber depth (ACD), anterior chamber area (ACA) and other parameters on ASOCT.

MAIN OUTCOME MEASURES: To identify ocular biometric associations and potential cut-offs for distinguishing glaucoma eyes from suspects.

RESULTS

Biometric measurements showed that the AL was the shortest, while ACD, ACA and ASOCT angle parameters were narrowest in eyes with EOPACG, as compared to EOPACS and EOPAC (p < 0.001; Bonferroni/Dunn test). Similarly, LV and LT were highest in eyes with EOPACG (p < 0.001). Logistic regression analysis revealed that ACD exhibited the highest predictive ability (ACD ≤ 2.73 mm, OR 4.36, AUC 0.72), followed by LT (LT ≥ 4.22 mm, OR 4.2, AUC 0.71) and ACA (ACA ≤ 17.24mm2, OR 3.04, AUC 0.7) for EOPACG.

CONCLUSIONS

This study highlights the significance of ocular biometric measurements, especially ACD and LT, which can assist in stratifying individuals with EOPACD for early detection of glaucoma. Thickening of the lens with the resultant crowded anterior chamber seemed to be the most prevalent biometric characteristic in eyes with frank glaucoma.