GLA Acts Synergistically in Treatment of Meibomian Gland Dysfunction
Meibomian Gland Dysfunction & Treatment
Meibomian gland dysfunction (MGD) is a common, yet often overlooked, chronic disease of the posterior eyelids. MGD is most often caused by an obstruction of the meibomian glands secondary to hyper-keratinization of the duct epithelium and plugging with a solidified secretion. These changes lead to alterations in the tear film lipid layer. Evaporation and tear osmolarity increase, resulting in dry eye signs and symptoms.
For patients with significant inflammation, systemic antibiotics and topical antibiotic/steroid combinations are used in the short term. Long-term treatment is aimed at controlling symptoms through eyelid hygiene.
Oral GLA May Enhance Hygiene Therapy
Supplementation with the omega-6 fatty acids linoleic acid and gamma-linolenic acid (GLA) has been reported to be of benefit in treating chronic inflammatory disorders such as rheumatoid arthritis. These fatty acids have also been found to reduce ocular surface inflammation and improve dry eye symptoms in patients with Sjögren’s syndrome and keratoconjunctivitis sicca.
In the present study, researchers assessed the effect of modest supplemental amounts of linoleic acid and GLA on MGD. The results suggest that oral fatty acids enhance eyelid hygiene in improving symptoms and reducing eyelid margin inflammation.
Study Design
Fifty-seven patients with MGD (27 men and 30 women) were randomly divided into 3 groups of 19. Group A received linoleic acid (28.5 mg) and GLA (15 mg) daily, while group B performed eyelid hygiene each day. Group C received both treatments.
Initially and after 60 and 180 days of therapy, all patients completed a self-evaluation questionnaire on ocular surface disorders and underwent slit-lamp examination. The following signs were evaluated: eyelid edema, eyelid margin hyperemia, meibomian secretion appearance, meibomian gland obstruction, conjunctival hyperemia, conjunctival papillae, corneal staining, and foam collection in the tear meniscus. The appearance of foam in the tear margin is indicative of meibomian gland malfunction.
Results
In total, 49 (86%) of the 57 patients completed the study; 2 patients dropped out at day 60, and 6 were lost at follow-up on day 180.
Significant improvement in symptoms occurred in all groups.
After 180-days, group A (oral fatty acids) showed reductions in meibomian gland obstruction (P = 0.0001) and secretion turbidity (P = 0.02), while group B (eyelid hygiene) had reductions in eyelid edema (P = 0.02), corneal staining (P = 0.01), secretion turbidity (P = 0.01), and meibomian gland obstruction (P = 0.0001).
In group C (combined therapy), the researchers noted reductions in eyelid edema (P = 0.003), corneal staining (P = 0.02), secretion turbidity (P = 0.0001), meibomian gland obstruction (P = 0.0001), and foam collection in the tear meniscus (P = 0.02).
Comments
The authors conclude that the combined omega-6 fatty acids and eyelid hygiene regimen improves symptoms and reduces eyelid margin inflammation in MGD more than either therapy alone.
The results suggest that the omega-6 fatty acids could play a dual role. They may have an anti-inflammatory effect and contribute to reducing eyelid edema, and the congestion of blood (hyperemia) in the eyelid margin and conjunctiva. In addition, the fatty acids may modify the lipid composition of meibomian secretion, which appears less turbid and dense after treatment. These changes may increase the effectiveness of eyelid hygiene.
The improvement in symptoms and clinical signs suggest that the fatty acids are a viable adjuvant therapy for standard treatment of MGD, and warrant further large-scale studies.