Time Course of Changes in Goblet Cell Density in Symptomatic and Asymptomatic Contact Lens Wearers

Purpose\ud\ud - To investigate longitudinal changes in goblet cell density (GCD) in contact lens (CL) wearers who do and do not develop symptoms of dry eye (DE).\ud\udMethods\ud\ud - Sixty healthy individuals fitted with daily disposable hydrogel CLs and 23 age-balanced non-CL–wearing controls underwent assessment using the 5-item dry eye questionnaire, noninvasive tear film break-up time measurement, ocular surface assessment, and phenol red thread test evaluation. Laser scanning confocal microscopy (LSCM) and conjunctival impression cytology (CIC) were used to assess GCD at baseline and follow-up visits at 1 week and 1 and 6 months. After 1 week, all CL wearers were categorized as those who were and were not symptomatic based on responses to the CL dry eye questionnaire-8 (CLDEQ-8). A linear mixed-model was used to examine changes in GCD over time.\ud\udResults\ud\ud - The global mean GCD of the 83 participants at baseline (before CL wear) was 476 ± 41 and 467 ± 52 cells/mm² using LSCM and CIC, respectively. After 6 months of CL wear, GCD was reduced by approximately 13% and 29% in asymptomatic (N = 29) and symptomatic (N = 17) CL wearers (all P < 0.001), respectively, observed with both LSCM and CIC.\ud\udConclusions\ud\ud - Contact lens wear induces a reduction of GCD over 6 months, which is exacerbated in those with DE symptoms. Either LSCM or CIC can be used to assess GCD in the conjunctiva