Relations between Dry Eye, Age and Gender and Meibomian Gland Loss

Purpose : Dry eye appears to be related to gender and age. The major cause of dry eye is reported to be Meibomian gland dysfunction, which may be related to loss of meibomian glands, observable by meibography. This study evaluated the relation between meibomian gland loss and age, gender and dry eye.Methods : Meibomian glands` morphology of the lower eyelid of 50 randomized selected patient reports (27 female; mean age 57 years; range 19-83 years) were analysed. Meibomian glands were evaluated using non-contact infra-red meibography (Cobra, BON, Lübeck, Germany) and area of meibomian gland loss (ML) was analysed using Phoenix meibography software 3.2 (BON). Subjects were grouped into normal and dry eye using the Dry Eye Tool Box`s (DTB) algorithm based on the three variables sum of lid-parallel conjunctival folds (nasal LIPCOF + temporal LIPCOF), non-invasive break-up time (NIBUT) and Ocular Surface Disease Index (OSDI). Correlations between age, OSDI and ML were analysed by Pearson correlation. ML related factors were analysed by multiple regression analyses. The ability of ML to diagnose dry eye status was evaluated by receiver operative characteristic curve (ROC). Results : Mean grade of LIPCOF Sum was 2.1 SD±1.90, mean NIBUT was 13.3s ±7.36, mean ML was 35.3% ±19.6 and the mean OSDI score was 15.2 ±10.12. 25 of the subjects had dry eye according DTB outcome. Age was not significantly correlated to ML (r=0.053, p=0.364) but OSDI was significantly correlated to ML (r=0.665, p<0.001). ML was significantly larger in the dry eye group (unpaired t-test, p<0.001). Multiple regression analyses (backwards) revealed gender and DTB outcome being the significant factors of ML (p<0.001), but not age. ML was significantly larger in female than in male (unpaired t-test, p>0.001). ML was a significant discriminator of DTB (area under the ROC =79.0%, p>0.001; best cut-off =30.8%) Conclusions : In this cohort of population dry eye and gender, but not age, were significantly related to ML. ML was larger in female than in male. Evaluation of ML by meibography appears to be an applicable dry eye test with good predictive ability.