Background: The purpose of this report was to examine the relation between clinical tests and dry eye symptoms in patients with dry eye disease.
Methods: Seventy-five patients with dry eye disease (ICD-9 code 375.15) were included in these analyses. There was no specific entry criterion for enrollment in addition to a previous dry eye diagnosis in this clinic-based sample. Patients represented varying types and severity of dry eye disease and were previously diagnosed by clinic attending doctors in this university clinic setting. The study examination included a symptom interview that assessed dryness, grittiness, soreness, redness, and ocular fatigue. The interview was followed by a clinical dry eye examination conducted in the following sequence: meibomian gland assessment, tear meniscus height, tear breakup time test, fluorescein staining, the phenol red thread test, Schirmer test, and rose bengal staining. Partial Spearman correlation coefficients, the Wilcoxon rank sum test, chi 2 test, and multivariate logistic regression were used to evaluate the relationship between dry eye tests and symptoms.
Results: Symptoms were generally not associated with clinical signs in patients with dry eye disease. There were no significant correlations between signs and symptoms after adjustment for age and artificial tear use. The rank of each clinical test result did not statistically differ when stratified by the presence of patient symptoms in Wilcoxon rank sum analyses. Likewise, the frequency of patient symptoms did not differ statistically when stratified by a positive clinical test result in chi 2 analyses. In multivariate logistic regression analyses, no clinical test significantly predicted frequently reported symptoms after adjustment for age and artificial tear use.
Conclusions: These results suggest a poor relation between dry eye tests and symptoms, which represents a quandary in dry eye clinical research and practice.