Dry eyes (2016-17) Linked to Meibomian Gland Dysfunction
Learn more about dry eye cause and treatment.
Researchers have long understood that post-menopausal women experience an increase in dry eye symptoms. Dry eyes are caused by insufficient tear film, or insufficient meibum to protect the tear film from evaporation.
Researchers were investigating the connection between hormonal changes in post-menopausal women and dry eye symptoms. The test subjects were nearly 50 post-menopausal women with dry eye ranging in age from 59 to 69 years old. They were 6 to 20 years past menopause and were not receiving hormone therapy.
The researchers looked at a number of standard tests and assessments used to evaluate dry eye conditions. They looked at the condition of the surface of the cornea, how comfortable eyes felt to the patients, how thick the tear fluid was and how rapidly the tear film broke up. They also investigated the health of the meibomian gland.
These glands are located above and below the eyes close to the eye lashes. They secrete meibum. Meibum is a thin oily substance that floats on top of the tear film helping to keep it from evaporating. Every time we blink the tear film and its protective meibum coating is redistributed evenly over the surface of the cornea.
The researchers found that the level of estrogen in the blood seems to be a main factor in the health of the meibomian glands, and that the resulting meibomian gland dysfunction as estrogen levels decrease is associated with increased dry eye symptoms.
Researchers: B. Golbiowski, N. Badarudin, et al
Published: Does endogenous serum oestrogen play a role in meibomian gland dysfunction in postmenopausal women with dry eye?< British Journal of Ophthalmology, February, 2017.
A previous study investigated the possible role of both testosterone and estrogen in postmenopausal women with dry eye. Nearly 200 postmenopausal women with an average age of 61 were included in the study.
They looked at blood levels of both hormones, the integrity of the meibomian glands and the thickness of the meibum layer on the surface of the eye.
There was no clear association between the hormone levels and the thickness of the meibum layer.
However, there was a significant link between "meibomian gland dropout (MG dropout)" and hormone levels. MG dropout refers to the deterioration or complete loss of the tissue that makes up the meibomian glands. As testoterone levels increased (relative to declines in estrogen), MG dropout also increased. The change was not so significant for estrogen levels alone decreasing.
Researchers: A.F. Ablamowicz, J.J. Nichols, et al
Published: Association Between Serum Levels of Testosterone and Estradiol With Meibomian Gland Assessments in Postmenopausal Women, Investigations in Ophthalmology and Visual Science, February, 2016.
Editor's Note: a related study also found that meibomian gland dterioration was severe in patients wearing silicone hydrogel contact lenses.1
1. M.C. Lin, T.H. Yeh, Mechanical Complications Induced by Silicone Hydrogel Contact Lenses, Eye Contact Lens, 2013, online in Medscape