MoCA-screen-positive status differs across intraocular pressure subtypes of primary open-angle glaucoma

Abstract

Background Cognitive vulnerability may differ across intraocular pressure-defined subtypes of primary open-angle glaucoma (POAG), but visually dependent cognitive-screening tasks and residual confounding complicate interpretation. Methods This single-center observational study included 93 patients with POAG [49 normal-tension glaucoma (NTG) and 44 high-tension glaucoma (HTG)]. A corrected Montreal Cognitive Assessment (MoCA) score <26 defined MoCA-screen-positive status. A vision-reduced MoCA-22 score was calculated by removing the eight points assigned to visuospatial/executive and naming tasks. Sequential NTG-vs.-HTG models added demographics, visual field index (VFI), retinal nerve fiber layer (RNFL) thickness, diabetes, and systolic blood pressure. Subtype-by-PSQI and subtype-by-RNFL interactions, strict peak-IOP classification, structure-function correlations, mood-adjusted PSQI models, and bootstrap internal validation were examined. Results MoCA-screen-positive status occurred in 44/93 participants (47.3%) and was more frequent in NTG than HTG (59.2% vs. 34.1%; crude OR: 2.80, 95% CI: 1.20–6.52; P = 0.017). The association remained in the fully adjusted sequential model (OR: 8.47, 95% CI: 1.81–39.61; P = 0.007) and after excluding six HTG participants with peak IOP <25 mmHg (OR: 6.74, 95% CI: 1.44–31.41; P = 0.015). Vision-reduced MoCA-22 was lower in NTG [18 (16, 19) vs. 19 (17.75, 20); P = 0.043], including after full adjustment (beta = −0.88, 95% CI: −1.63 to −0.14; P = 0.020). Subtype interactions were not significant for PSQI (P = 0.604) or RNFL (P = 0.082). In exploratory subtype models, study-defined history of low blood pressure study-defined history of low blood pressure (<110/<65 mmHg; recorded only among NTG participants), higher PSQI, and thinner RNFL were associated with screen-positive status in NTG; thinner RNFL was associated in HTG. Apparent AUCs were 0.940 (95% CI: 0.869–0.988) for NTG and 0.892 (0.763–0.989) for HTG; bootstrap-corrected AUCs were 0.900 and 0.851. Conclusion NTG was associated with more frequent MoCA-screen-positive status and lower vision-reduced MoCA scores after measured visual, vascular, and metabolic adjustment. The subgroup correlates and model performance remain exploratory and require prospective external validation; the present data do not establish distinct causal NTG and HTG phenotypes.