PSS13 Risk Factors for Chronic Ocular PAIN: Evidence from a Literature Review

Abstract

Chronic ocular pain (COP) is a persistent eye pain lasting for a period longer than 3-months. There is paucity of data to understand the etiological factors for COP. The objective of this review was to summarize the literature on the risk factors for COP. A targeted literature search was performed for publications in English from database inception to 19th August 2019 in Embase and Ovid platforms. Studies reporting risk factors for ocular pain were included. The review identified 84 publications reporting 55 unique risk factors (110 associations) for COP. Laser-assisted in situ keratomileusis (LASIK), dry eye disease (DED), pseudophakic bullous keratopathy (PBK), Sjögren's syndrome, photorefractive keratectomy (PRK), cataract surgery (CS), ocular trauma, migraine, blepharitis, keratitis, graft versus host disease (GVHD), herpes zoster, were the commonly reported risk factors for COP. These risk factors were broadly categorized into two types, i.e. ocular (surgical procedures, ocular inflammation, ocular melanoma and infections) and non-ocular (drug-induced and auto-immune diseases). Based on the number of publications and sample size (n), surgical procedures were the most common contributor for COP [LASIK: 18 publications; [n/total sample size (N) =3267/3283], PRK: 4; (n/N=159/159), CS: 3; (n/N=92/230)], followed by DED [9 publications; (n/N=1053/3097)], ocular inflammation [conjunctivitis: 2; (n/N=220/220), blepharitis: 2; (n/N=145/2610), scleritis: 2; (n/N=57/2604) and keratitis: 3; (n/N=20/2607)], ocular infection (7; n/N=114/178), autoimmune diseases [Sjögren's syndrome: 5; (n/N=46/57) and GVHD: 2; (n/N=28/115)], ocular trauma (6; n/N=112/136), PBK (4; n/N=30/167) and ocular melanoma (4; n/N=6/102). Patients who underwent ocular surgeries, DED patients, ocular inflammation or infection, ocular trauma and Sjögren's syndrome, seem major causes for developing COP. Ocular surgeries (LASIK, PRK, CS), DED, ocular inflammation, Sjögren's syndrome, seem to be common risk factors for developing COP. Heterogeneous studies in measuring ocular pain symptoms, paucity of data for COP definition and pain duration were the limiting factors of this review.