Abstract
Purpose: :
To streamline habitual ocular surface symptom questions from the Dry Eye Questionnaire (DEQ) to best discriminate between groups of patients with varying self-assessed severity of dry eye (DE).
Methods: :
Subjects (n = 276) in 2 IRB approved DE studies conducted in 2002 and 2005 received the DEQ at baseline along with a question on self-assessment of DE severity. The sample included 46 subjects with severe DE (including Sjogren’s syndrome), 107 with moderate, 77 with mild and 46 controls without DE symptoms or a clinical DE diagnosis. Individual items from the DEQ were first tested to determine those with the best correlations to self-assessed DE severity (Spearman). From the subset of highly correlated items, combinations of questions were tested to establish the most efficient set to discriminate between self-assessed DE severity groups by selecting the combination with the greatest difference between groups by ANOVA with Bonferroni post hos analysis.
Results: :
Frequency of watery eyes (r = 0.476), discomfort (r = 0.407), and dryness (r = 0.349), early (AM) and late day (PM) discomfort intensity (r = 0.360, 0.422), AM and PM dryness intensity (r = 0.393, 0.363) and bother from discomfort and dryness (r = 0.310, 0.334) were all significantly correlated with self-assessed severity (p<0.01, all items). Other habitual symptom items were not significantly correlated with self-assessed DE severity. Scores summing all 9 significant items, 7 items (no AM intensity), and 5 items (no AM intensity or bother) were tested for their ability to discriminate between groups. The 5-item scores were best at discriminating DE severity; 5-item scores were (mean and SD): Severe 14.9 (2.3), Moderate 11.4 (3.3), Mild 8.6 (3.1) and None 2.7 (3.2), (ANOVA, p<0.0001).
Conclusions: :
Dry eye clinical practice is hampered by the lack of objective tests with which to assess severity, establish the DE diagnosis or assess treatment progress. The short DEQ-5, the sum of 5 questions: Frequency and PM Intensity of each Dryness and Discomfort plus Frequency of Watery Eyes efficiently discriminated the self-assessed severity of DE subjects and normal controls. Further research will determine whether these symptoms can be mitigated with treatment and if self-assessed DE severity will adjust with a reduction in symptoms.
Keywords: cornea: tears/tear film/dry eye