Change in Discomfort- and Vision-Related Symptoms of the Ocular Surface Disease Index in Patients with Neuropathic Corneal Pain

Abstract

Purpose : The Ocular Surface Disease Index (OSDI) is a widely used questionnaire for assessment and follow-up of dry eye disease, but has not been assessed for neuropathic corneal pain (NCP). It generates a total score, using itemized severity scores of 12 symptoms. However, since the response to treatment varies for different symptoms in NCP, the overall score may not be a true representative of symptom severity. Hence, we undertook a study to evaluate discomfort-related (DR) and vision-related (VR) symptom subscores of the OSDI over time in patients with NCP.

Methods : A retrospective, observational study was undertaken in 53 symptomatic patients with a clinical diagnosis of NCP. The 12-items on OSDI were sub-divided into DR (3 questions: number 1-3 on OSDI) and VR (6 questions: number 4-9 on OSDI) questions. Overall OSDI sub-scores and total scores were calculated at baseline and between 9-12 months using the formula: total score x 25/number of questions. Mean ± SD of the sub-scores and total scores for both the visits was compared using two-tailed students’ t-test. Pearson correlation was used to calculate the relationship of DR and VR symptoms. A p-value of <0.05 was considered statistically significant.

Results : The total OSDI score showed a minimal change from 50.722 ± 25.866 to 48.387 ± 22.525 (p-value=0.44). For the DR questions, the subscore (mean ± SD) decreased from 52.44 ± 26.01 at baseline to 45.83 ± 24.27 at 9-12 months (p-value=0.03), while it increased from 43.18 ± 26.3 at baseline to 44.91± 27.68 at 9-12 months (p-value=0.66) for the VR questions. Furthermore, the correlation of DR to VR symptoms on OSDI also declined between the 2 visits from 0.742 to 0.694 (p-value <0.001).

Conclusions : Our study shows that the utility of total OSDI score is limited in NCP patients; subscores provide a useful tool during follow-up, as a shift from DR to VR symptoms is seen but is not reflected by the overall score. This shift can also be used as an early indicator of response to treatment, in patients with minimal change in overall OSDI score.

This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.