The epidemiology of ocular itch by dry eye symptoms and signs

Abstract

Purpose : The epidemiology of ocular itch (OI) has not been well studied and the classic teaching is that its presence indicates ocular allergy; however, newer data on the pathophysiology of itch suggests that other pathways are involved and are shared between the skin and ocular surface. Our objective is to evaluate associations between sensations of OI and dry eye (DE) symptoms and signs.

Methods : We performed a cross-sectional study of 324 patients that were seen in the Miami Veterans Affairs eye clinic. An evaluation was performed consisting of questionnaires regarding OI, DE symptoms, neuropathic-like ocular pain (NOP) descriptors followed by a comprehensive ocular surface examination. Subsequent analyses were performed to examine for differences between those with and without complaints of OI.

Results : The mean age was 62 years with 92% being male. Of the 324 patients, 254 individuals reported OI: 130 rated the sensation as “mild” in intensity, 79 “moderate” and 45 “severe”. DE symptoms measured via Ocular Surface Disease Index questionnaire (OSDI) were higher in patients with moderate–severe (M-S) OI (47.4 standard deviation (SD) 24.2) compared to their counterparts with mild or no OI (29.5 SD 21.5; OSDI of 25.1 SD 25.4, respectively, p<0.0005). NOP complaints, demonstrated via the neuropathic pain symptom inventory modified for the Eye (NPSI-Eye), were also higher in patients with M-S OI (33.8 SD 23.7) compared to those with mild or no OI (15.3 SD 16.2; 12.7 SD 17.5, respectively, p<0.0005). DE signs, on the other hand, were not significantly related to OI, but those with M-S OI had a lower frequency of ocular surface inflammation (30% compared to 42% with mild and 43% with no OI, p=0.08). When evaluating DE discordance scores, those with M-S OI had higher discordance scores (symptoms disproportionate to signs) (0.35 SD 0.28) compared to individuals with mild (0.17 SD 0.24) or without (0.11 SD 0.26) OI. Patients with M-S OI additionally had higher non-ocular pain, depression, and post-traumatic stress disorder scores, compared to those with mild or no OI symptoms.

Conclusions : Subjects with M-S symptoms have more severe DE symptoms, NOP complaints and non-ocular pain. However, DE signs did not statistically significantly correlate with OI.

This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.