Abstract
Abstract: :
Purpose: In clinical studies of the safety and efficacy of dry eye treatments, careful consideration of entry criteria for subjects is essential, as no single definitive test for dry eye is generally accepted. In most studies, specific combinations of signs and symptoms are used to qualify study subjects. Here, we examine the validity of using a single symptom variable of self-assessed ocular dryness to categorize patients in a multi-site controlled clinical trial of a new dry eye treatment. Methods: 217 dry eye subjects were assessed at 10 study sites as part of a controlled, randomized clinical trial comparing the efficacy and safety of 3 eye drop formulations. Entry criteria included either a Schirmer test result (with anesthesia) between 2 and 8 mm in 5 min, and/or a fluorescein tear break-up time (TBUT) ≤ 10 sec. For symptoms, only Mild or Moderate dry eye subjects were included in the trial based on self-assessment of their ocular discomfort due to the symptom of "Dryness" on a 0-4 scale from "none" to "severe". The Table lists the characteristics of frequency of symptoms, presence of discomfort, and interference with activity that were provided to subjects in text form. Once admitted to the study, additional variables recorded included the Ocular Surface Disease Index© (OSDI) score, and corneal and conjunctival staining. Results: 139 Mild (dryness score 2) and 78 Moderate (dryness score 3) subjects were enrolled in the study. Comparisons of OSDI scores, Schirmer values, TBUT, and combined staining scores between the 2 symptom groups showed greater severity for moderate patients for all variables (p < 0.03). Conclusions: These results demonstrate that, for mild to moderate dry eye subjects, self-assessment of discomfort due to "dryness" correlates well with objective signs of dry eye, as well as with more detailed surveys such as OSDI. Table: Definition of single score for symptom of Dryness.
Keywords: cornea: tears/tear film/dry eye • cornea: clinical science