On this episode of Interventional Mindset, Preeya K. Gupta, MD and Cecilia Koetting, OD, FAAO, Dipl. ABO discuss a recent study showing a strong link between Demodex blepharitis (DB) and meibomian gland dysfunction (MGD), emphasizing early diagnosis to prevent gland atrophy.
DB and MGD study overview
Elizabeth Yeu, MD and Dr. Koetting conducted a retrospective review of about 400 patients aged 18 or older.1 It examined patients with MGD, defined as grade 2 to 4 meibum quality or grade 1 to 4 atrophy. The following MGD signs were evaluated: telangiectasia, meibum expressibility, meibum quality, and meibography.
The patients were divided into two groups:1
- Eyes with moderate to severe Demodex blepharitis (collarette grades 2 to 4, or >10 collarettes)
- Eyes with collarette grade 0 (0 to 2 collarettes)
Outcome measures compared the mean telangiectasia score, meibum expressibility score, meibum quality score, and meibomian gland atrophy score between the two groups. Patient's right and left eyes were analyzed separately.1
For pearls on treating MGD in pre-operative patients, check out MGD and the Cataract Patient: When Right for the Patient is Right for the Practice!
Findings from the analysis
There was a positive correlation between collarette grade and the scores for telangiectasia, meibum quality, and meibomian gland atrophy in both the right and left eyes, even after adjusting for age.1
Among patients with MGD, defined as meibum quality grades 2 to 4 or atrophy grades 1 to 4, 45% had Demodex blepharitis. Furthermore, of the patients exhibiting moderate to severe Demodex (with 10 or more collarettes), 96 to 99% were diagnosed with MGD.1
Interestingly, the study found no association between Demodex blepharitis and lower meibomian gland expressibility scores.1
Clinical implications of this study
These findings suggest that patients with Demodex blepharitis will have meibomian gland dysfunction. Consequently, clinicians should regularly check their patients for Demodex infestations and signs of MGD, and treat both conditions as necessary.1
Drs. Gupta and Koetting discuss the importance of addressing Demodex blepharitis early to reduce the risk of severe gland atrophy. Once atrophy occurs, it is irreversible, making prevention crucial.
Dr. Koetting stressed the importance of initiating treatment even when patients are not symptomatic. Dr. Gupta notes that with newer treatments such as lotilaner (1 drop twice daily for 6 weeks), patients often remain free of recurrence for at least 1 year, if not longer.
Patients with conditions such as rosacea may face higher risks since they are more prone to blepharitis and have increased Demodex mite densities. In rosacea, Demodex proliferation appears to be part of a spectrum in which mites trigger inflammation, leading to further mite growth and disease progression.2
There is also an increasing concern about Demodex blepharitis in children. Recent research indicates a strong link between Demodex infestation and pediatric chalazia, suggesting that children with recurrent chalazia should be assessed for Demodex.2 Additionally, Demodex should be viewed as a potential risk factor for developing chalazia in children.
Final thoughts
Dr. Koetting closes with “an ounce of prevention is worth a pound of cure.” While clinicians might not cure MGD, preventing it remains important for patients.
