Purpose
Testosterone deficiency has been shown to promote meibomian gland dysfunction whereas the ocular surface effects of estrogens are more controversial although receptors are found in the meibomian glands. The purpose of this work was to determine if there is an association between serum levels of testosterone and estradiol with meibomian gland dropout and expressibility.
Methods
The data used for this analysis (right eye only) were collected from 230 post-menopausal women with an average age of 61.6 (± 9.1) years. Meibography images were used to assess meibomian gland dropout on the central 2/3 of the eyelid (scored from 1 = no partial glands to 4 = >75% of image contains partial glands) and biomicroscopy was used for assessing meibomian gland expressibility (scored from 0 = minimal pressure to 3 = heavy pressure needed to express). Venous blood samples were drawn for serum hormone level analysis. The Kruskal-Wallis test was performed for both serum testosterone and estradiol using SAS 9.4 (Cary, NC).
Results
The mean serum testosterone levels (ng/dL) and estradiol levels (pg/mL) for meibomian gland dropout and expressibility severity groups are shown in the tables. Statistical analysis of testosterone levels (H = 4.20, p = 0.24) and estradiol levels (H = 1.42, p = 0.70) between gland dropout severity groups revealed no significant differences. Similarly, analysis of testosterone (H = 5.23, p = 0.16) and estradiol (H = 1.81, p = 0.61) levels between expressibility groups revealed no significant differences.
Conclusions
Although able to down-regulate keratinization genes in the meibomian glands (shown in a mouse model by Shirra, et al), serum testosterone levels in this analysis show no association with varying severity gradings of both meibomian gland dropout and expressibility. While the majority of estradiol serum levels measured in this study were in the normal range for post-menopausal women, these results may indicate that serum hormone levels do not reflect the local ocular hormonal environment.