Vision-related quality of life in Polish patients with keratoconus: A cross-sectional study using the KORQ questionnaire

PURPOSE: To evaluate the impact of keratoconus on visual quality and quality of life among Polish patients by integrating subjective assessments using the Keratoconus Outcomes Research Questionnaire (KORQ) with objective clinical measurements. METHODS: A total of 100 patients (80% men, 20% women; median age: 39 years) with clinically diagnosed keratoconus completed the locally validated Polish version of the KORQ, including two subscales: Activity Limitation (18 items) and Symptoms (9 items). Objective data collected included best-corrected visual acuity (BCVA), corneal topography, pachymetry, and higher-order aberrations (HOA). Statistical analyses included biweight midcorrelations and robust linear regression models adjusted for age and gender. RESULTS: The mean Activity Limitation score was 51.53 (SD = 17.19) and the Symptoms score was 55.60 (SD = 16.14), indicating moderate functional impairment and symptom burden. The most challenging activities were night driving (mean = 2.06), seeing small distant objects (mean = 2.09), and coping with poor lighting (mean = 2.05). The most bothersome symptoms were distorted vision (mean = 1.84), sensitivity to smoke (mean = 2.05), and dusty environments (mean = 2.01). Higher-order aberrations, especially in the worse-seeing eye, showed the strongest associations with KORQ scores across both subscales (e.g., for Symptom subscale: HOA: β = 2.84; p = 0.004; vertical coma: β = 5.83; p = 0.019), while BCVA in the better-seeing eye was significantly associated with both lower symptom burden (β = -9.83; p = 0.047) and functional limitation (β = -12.13; p = 0.042). Traditional structural parameters, such as Kmax and corneal thickness, showed no significant predictive value. CONCLUSIONS: Keratoconus significantly impairs visual functioning and causes a high symptom burden among Polish patients. Best-corrected visual acuity and higher-order aberrations, especially in the worse-seeing eye, are the strongest predictors of reduced vision-related quality of life. These findings emphasize the need to focus clinical management on improving optical quality, rather than solely correcting structural corneal features.