Purpose: To determine the correlations among symptoms and signs of dry eye disease (DED) in the Dry Eye Assessment and Management (DREAM) study.
Methods: A total of 535 patients with moderate-to-severe DED were assessed for symptoms using the Ocular Surface Disease Index (OSDI) and four DED signs in both eyes (conjunctival lissamine green staining, corneal fluorescein staining, Schirmer's testing, and tear break-up time (TBUT)) following standardized protocols at baseline and follow-up visits (months 3, 6, and 12). Spearman correlation coefficients (rho) were calculated for correlations among symptoms and signs of DED at baseline and among changes in symptoms and signs from baseline at 12 months. The confidence intervals and p-values for correlation coefficients were calculated using a cluster bootstrapping to account for inter-eye correlation.
Results: At baseline, OSDI total score was not correlated with signs; however, OSDI subscale score of ocular symptoms was weakly correlated with corneal staining score (rho = 0.14, p = .002) and Schirmer test score (rho = 0.11, p = .01). There were statistically significant correlations among the four signs (p < .001), with absolute correlation coefficient ranging from 0.14 (conjunctival staining score vs. TBUT) to 0.33 (conjunctival staining score vs. cornea staining score). The correlations among changes in symptoms and signs were weaker, with the highest correlation between change in conjunctival staining and corneal staining (rho = 0.21, p < .001).
Conclusions: Consistent with previous studies, among DREAM participants with moderate-to-severe DED at baseline, correlations of DED symptoms with signs were low and correlations among four objective signs were low to moderate. The correlations among changes in symptoms and signs were even weaker.
Keywords: Correlation; dry eye; signs; symptoms.