Assessment of dry eye questionnaires in patients with and without glaucoma

Aim To compare the results of the Ocular Surface Disease Index (OSDI), 5-item Dry Eye Questionnaire (DEQ-5) and Symptom Assessment Questionnaire iN Dry Eye (SANDE) in patients without glaucoma and with glaucoma at different stages of severity. Methods Cross-sectional study including patients who underwent visual field (VF) testing, completed three dry eye disease (DED) questionnaires and had ocular surface examination. Glaucoma severity was staged by averaging the severity grade of both eyes using mean deviation (MD) thresholds as mild (MD≥−6dB), moderate (−6>MD≥−12 dB) and advanced (MD<−12 dB). Questionnaire results, pairwise correlations and predictors for each questionnaire result were assessed. Results 147 patients with a mean age of 65.8±12.5 years were included. OSDI showed moderate-to-high correlations with DEQ-5 and SANDE in patients without glaucoma (n=43) and with mild-to-moderate (n=32and n=56) VF damage (always ρ≥0.55; p<0.01 with DEQ-5 and ρ≥0.5; p<0.01 with SANDE); while correlations became low and non-significant in advanced glaucoma (n=16) (ρ:0.38; p=0.60and ρ:0.41; p=0.464 with DEQ-5 and SANDE, respectively). Conversely, DEQ-5 and SANDE always showed significant correlations (ρ≥0.66; p<0.01). Linear regression showed the OSDI to be the only questionnaire affected by mean MD (p=0.002). Additionally, glaucoma patients were more frequently defined as symptomatic for DED using the OSDI compared with the DEQ-5 (65.4% vs 51.9%; p=0.0082). Conclusion DED questionnaires showed different behaviours in patients with glaucoma. The OSDI failed to maintain its correlation with both the DEQ-5 and SANDE in advanced glaucoma stages and was the only questionnaire influenced by VF damage. Questionnaire choice may influence how DED symptoms are captured in glaucoma patients, particularly in advanced stages.