OBJECTIVE: To assess quality of life (QOL) as measured by patient-reported outcomes (PRO) within the iStent inject pivotal trial.
DESIGN: Randomized controlled trial analysis of secondary outcomes.
METHODS: The Vision Function Questionnaire (VFQ-25) and Ocular Surface Disease Index (OSDI) questionnaire were administered at baseline and at months 1, 6, 12, and 24. PRO responders were defined as patients reaching improvement based on minimally important differences.
RESULTS: A total of 505 patients were randomized (386 iStent inject [Glaukos], 119 surgery alone). The iStent inject group exhibited a greater percentage of PRO responders across all follow-up visits over 24 months, averaging 58.0% vs 45.8%; P < .05 for VFQ-25 composite scores and 56.7% vs 48.9%; P < .05 for OSDI composite scores. Odds of being a responder in the iStent inject group was 60% (P < .05) higher for the VFQ-25 and 32% (P > .05) higher for the ODSI. Driving (49.0% vs 28.8%; P < .05), ocular pain (59.3% vs 47.2%; P < .05), and general vision (71.8% vs 60.0%; P < .05) were the VFQ-25 subscales responsible for differences between treatment groups. At month 24, 76.5% of VFQ-25 responders and 62.5% of nonresponders were medication free regardless of treatment group (P < .05).
CONCLUSIONS: Exploratory analysis suggests that by reducing medication dependence, implantation with the micro-scale iStent inject device with cataract surgery may improve QOL vs cataract surgery alone over 24 months, with improvements influenced by ocular symptoms and vision-related activities.