Meibomian gland dysfunction is the primary determinant of dry eye symptoms: Analysis of 2346 patients

Abstract

Purpose: To determine relative contributions of various ocular surface clinical signs and predisposing factors to the magnitude of dry eye symptoms.

Methods: Clinical audit data were prospectively collected for newly referred dry eye patients. All 2346 patients had an initial visit evaluation of the Ocular Surface Disease Index (OSDI), and a detailed ophthalmic examination including tear breakup time (TBUT), ocular surface fluorescein staining, Schirmer's I test. Among the participants, 1414 had number of liquid meibum expressing glands (NLMEG) evaluated on standard force expression. Other variables collected included history of glaucoma or glaucoma surgery, and history of allergies.

Results: In patients aged 46.2 ± 14.8 years, 77.4% were women and 87.1% Chinese. The mean ± SD OSDI was 35.2 ± 21.7. On univariate analysis, higher OSDI was associated with glaucoma diagnosis (p = 0.003), glaucoma surgery (p = 0.002), greater temporal corneal staining (p = 0.002), reduced NLMEG (p < 0.001), and higher inferior forniceal papillary grade (p < 0.001). OSDI was not significantly associated with gender, TBUT, Schirmer's I test values, or the use of cyclosporine eyedrops. On multivariate regression, higher OSDI scores were associated with fewer NLMEG (p = 0.002) and increased lower eyelid forniceal papillary grading (p = 0.002). Corneal staining, glaucoma status and glaucoma surgery were not significantly associated with OSDI. Logistic regression showed that severe symptoms (OSDI>32) was associated with <2 NLMEG [OR(95%CI): 1.34(1.08-1.66)], and presence of inferior eyelid forniceal papillae [1.50(1.17-1.91)].

Conclusions: Meibomian gland dysfunction (MGD) and lower forniceal papillary reaction had significant contributions to the severity of symptoms, in contrast to traditional dry eye signs. MGD should be objectively assessed and treated to improve symptoms.

Keywords: Allergic conjunctivitis; Dry eye; Dry eye symptoms; Meibomian gland dysfunction; Ocular surface disease; Questionnaire.