1. Yousef A Alghamdi, MD; Allison L McClellan, OD; Nabeel M Shalabi, MD Anat Galor, MD, MSPH Supported by the Department of Veterans Affairs, Veterans Health Administration, Office of Research and Development, Clinical Sciences Research and Development’s Career Development Award CDA-2-024-10S (Dr. Galor), NIH Center Core Grant P30EY014801, Research to Prevent Blindness Unrestricted Grant, Department of Defense (DOD- Grant#W81XWH- 09-1-0675 and Grant# W81XWH-13-1-0048 ONOVA) (institutional). Miami Veterans Administration Medical Center, ‎ Bascom Palmer Eye Institute, University of Miami, Miami, FL The authors have no financial interests to disclose

2. Introduction Meibomian gland dysfunction (MGD) Chronic, diffuse abnormality of the meibomian glands Characterized by terminal duct obstruction and/or qualitative/quantitative changes in the glandular secretion Leading cause of evaporative dry eye Prevalence of MGD ranges from 35% to 61% Study countrynFrequencyReference USA 398 38.9% (95% CI, 34.0– 44.0) Hom et al. China115 34.8% (95% CI, 26.2– 44.4) Zhang et al. Malaysia231 43.0% (95% CI, 36.7– 50.0) Ong BL Japan5461.0% (95% CI, 46.6– 73.9) Shimazaki et al. Frequency of MGD in Selected Clinical Populations

3. Many gaps in the literature regarding the epidemiology of MGD Most clinic based studies have large female populations Little has been published on associations between specific MGD sub-types (meibum quality versus vascularity, for example) and patient profiles Introduction Cont.

4. Purpose To study the epidemiology of meibomian gland dysfunction (MGD) in an elderly, predominantly male population.

5. Methods Patients with normal eyelid and corneal anatomy were prospectively recruited from the Miami Veterans Affairs eye clinic. Patients were assessed for… Dry eye symptoms Dry eye questionnaires (dry eye questionnaire 5 (DEQ5) Ocular surface disease index (OSDI)) Dry eye signs Osmolarity Tear break up time Corneal staining Schirmer’s strips with anesthesia

6. Main Outcomes Measured Correlations between meibomian gland (MG) parameters and local (dry eye) and systemic (demographics) factors The studied MG parameters were eyelid vascularity and meibum quality; a score of ≥2 in either parameter was considered abnormal

7. Results Mean age of the 118 patients was 65 (SD=11); 86% were male and 62% had at least one abnormal MG parameter (vascularity 22% (n=26), abnormal quality 58% (n=68)) Demographically, white patients were more likely to have abnormal vascularity than non-whites (35% (n=23) versus 2.5% (n=1) and 15% (n=2) for blacks and others respectively, (p < 0.0005)) Ethnicity and age did not correlate with MG parameters

8. Results MG abnormalities were weakly associated with each other (r=0.19, p=0.51) and not at all with dry eye symptoms (r=0.007-0.17, p>0.05 for all) Some MG parameters were associated with some dry eye signs (osmolarity with vascularity, OD only r=-0.2, p=0.03, TBUT with both vascularity and meibum quality, both eyes r=-0.25-0.35, p<0.05, Schirmer with vascularity, OD only r=-0.2 (p=0.03) Corneal staining was not associated with MG parameters

9. Conclusion: MGD is a frequent finding in an elderly, predominantly male population with racial differences noted in the frequency of abnormal eyelid vascularity but not in MG quality

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