Researchers found that a meibomian gland loss rate higher than 50% is accompanied by increased osmolarity, redness and staining of the ocular surface. Put another way, if you see these signs clinically, expect significant compromise of the meibomian glands. They believe that aging likely affects gland morphology, as well as corneal staining and tear volume. In this study, only corneal staining was correlated with meibomian gland loss when age was considered as a covariant.

The study took into account both the upper and lower eyelids in 161 patients who were then classified into five groups according to total meiboscore. Researchers found no differences in tear break-up time and Schirmer test in the different groups, indicating no significant differences in symptomatology.

To assess the real impact or influence of the meibomian gland loss in ocular surface parameters that age may also influence, researchers believe it’s necessary to compare age-matched groups. However, when age was covariant, the relationship between gland loss and meibum quality was absent. Meibum quality could be decreased either because of a higher amount of gland loss or because of it naturally decreased with ageing. Researchers suggest that determining the normal threshold of ocular and tear film surface parameters for each age range could help assess the real contribution of meibomian gland loss.