A Q&A with Mitchell A. Jackson, MD
AJMC®: Demodex blepharitis has a high estimated prevalence in the United States. However, few US studies of this disease exist. Why is this disease so understudied here?
JACKSON: The main reason Demodex blepharitis is understudied is that we don't have a good treatment for it—at least, we don’t have one yet. Hopefully, we will soon have a good treatment for this disease in the United States, based on the results of clinical trials and FDA approval.
Demodex blepharitis also can be hard to diagnose. Most eye care professionals forget to tell patients to look down [while performing the eye exam] to observe the upper lashes. We look at the eyes and the lower lids, but we forget to look at those upper lashes where the collarettes are located. Collarette presence defines infestation with Demodex mites for diagnostic purposes.
AJMC®: During the 2022 ASCRS [American Society of Cataract and Refractive Surgery] Annual Meeting held in April 2022, you presented the results of the Atlas Continuation study, which examined the clinical burden of Demodex blepharitis.1 Before the study, what was known about how this disease impacts patients?
JACKSON: Demodex mites, which are among the most common ectoparasites detected in humans, come in 2 forms. The first is D folliculorum, which are found in clusters in the lash root and lash follicle, where they feed on sebum and follicular epithelial cells. The second is D brevis, which are shorter in length, more solitary, and prefer to reside in the meibomian glands. D brevis is associated with blepharitis, meibomitis, meibomian gland dysfunction, recurrent chalazion, blepharokeratitis, blepharoconjunctivitis, and pterygium—all things on the ocular surface. That's the impact it has in terms of the ocular world. D brevis has some implications in nonocular disease, as well, such as folliculitis rosacea, seborrheic dermatitis, perioral dermatitis, scalp hair loss, and even basal cell carcinoma. It has a lot of implications throughout the body besides just the ocular implications.
AJMC®: What prompted you to study Demodex blepharitis?
JACKSON: Currently, we use a variety of products to [manage] the disease, but these products are not indicated for the treatment of Demodex blepharitis. These products can work partially or on a short term, and they might give some symptom relief, but they may not eradicate the Demodex itself. The Atlas Continuation study's main purpose was to evaluate the impact of Demodex blepharitis on visual function, daily activities, and motivations for seeking care.1 The investigators looked at the impact and burden of Demodex blepharitis on a patient's quality of life and visual function. We wanted to know if it is really worth finding a treatment for Demodex blepharitis. We wanted to see if [the disease] is really impacting life, visual function, and daily activities in a way in which you really realize, “We have to look for a treatment for this, because there's an impact.”
AJMC®: How did you select the patients for the Atlas Continuation study?
JACKSON: A total of 20 ophthalmic and optometric eye care professional centers in the United States were recruited for this observational study; clinicians at these centers screened for patients with Demodex blepharitis. The patient criteria included having at least 1 mite per lash, more than 10 collarettes, and mild or more severe erythema of the upper lid margin. Patients then filled out a questionnaire about symptoms, impact on daily living, and [disease] management experience.
The results of this Atlas Continuation study were presented at the ASCRS Annual Meeting; it is a continuation of the Atlas study presented at the 2021 ARVO [Association for Research in Vision and Ophthalmology] Annual Meeting, which included 311 patients. A total of 524 patients qualified and participated in this Atlas Continuation study with a mean age of 66 years (± 14 years); 56.7% of the patients were women.
We found that patients were seeking care because no one was diagnosing [the disease], and these were symptoms patients were experiencing for at least 2 years. Patients were really struggling with the disease, but they were not being diagnosed. That's the main thing. About 68% of patients experienced signs and symptoms of Demodex blepharitis over 2 years, 32% of patients saw their eye doctor at least twice, and 20% of these patients saw their doctor at least 4 times, yet nearly 60% never received a diagnosis of blepharitis or Demodex blepharitis.
This is why it's so important for every eye care professional to have patients look down during their eye examinations to look for collarettes. It's crazy how many patients experience signs and symptoms for that long without being diagnosed, and most of the patients had reported their symptoms. The top 3 symptoms reported were itchy eyes or eyelids, dry eye, and foreign body sensation. Some 55% of patients had itchy eyelids or itchy eyes, 46% had dry eye, and 23% had foreign body sensation.1 There were a variety of other symptoms as well—tearing, blurred vision, red eyes, gritty eyes, puffy eyelids, flaking from the eyelids, loss of eyelashes, and eyelids sticking together—but the top 3 were itchy eyes, dry eyes, and foreign body sensation.
This really showed us that patients had Demodex blepharitis, they were struggling, and no one was diagnosing it, never mind treating it. This is a good discovery. These study results really showed the need for diagnosis and a way to diagnose it. There will be a need for a treatment when eye care professionals are better trained to make the diagnosis.
AJMC®: How does Demodex blepharitis impact patients’ daily lives?
JACKSON: In the Atlas Continuation study, we observed that the most common burdens on patients were difficulty driving at night, which 47% of patients reported, and feeling conscious of their eyes all day, which also was reported by 47% of patients. This means that patients’ eyes itched or they felt like Demodex blepharitis caused a negative appearance of their eyes all day. Overall, 80% of patients said the disease negatively affected them in some way.1
Further, 34% of the women said that they had difficulty wearing makeup, and 30% of all patients said that they needed additional time for their daily hygiene routine, because their eyes required more care than did those of the average individual due to Demodex blepharitis.1 It definitely impacts their lives.
AJMC®: The Atlas Continuation study found that almost half the patients (46%) were using warm compresses or wipes, and almost half (47%) were using artificial tears. Still, 43% of patients had discontinued these or other treatments due to adverse effects or low efficacy.1 Is this consistent with your clinical experience?
JACKSON: Yes, because nothing is really treating Demodex blepharitis. In the study, the [management options] most people tried were lid wipes or tea tree oil, and almost everyone was already using artificial tears. Of all these [management options]—whether it was artificial tears, warm compresses, lid wipes, an antibiotic-steroid combination, tea tree oil, or an oral antibiotic like doxycycline, which is good for meibomian gland function—46% of patients who discontinued their regimen did so because of efficacy or tolerability issues. None of these options, as we discovered, are effective in mitigating or eliminating Demodex blepharitis. That's the problem. These are all the [management options] we use now, because we don't have anything else. This shows the need for the treatment, because these [management options] don't work, patients aren't diagnosed properly, and it's affecting their lives and activities of daily living negatively.
The results of the Atlas Continuation study showed the psychosocial and functional impact of the disease. We have to continue with eye care professional education on how to diagnose Demodex blepharitis and make sure that it's getting diagnosed and not missed. Once we have a treatment for Demodex blepharitis, eye care professionals will be more likely to look for it, because they then will be able to treat it and hopefully say, “Hey, that's why some of these people aren't getting better! We've been [managing] it with all these other regimens, and the patients really had Demodex.”
AJMC®: Given the multitude of products currently being used to manage Demodex blepharitis, what are the costs associated with the misdiagnosis of this disease?
JACKSON: If patients are coming back [to their providers] at least 2 to 4 times, there are additional costs. There is some ancillary testing associated with cost, such as tear osmolarity or dynamic meibomian imaging, and then there’s the cost of pharmaceuticals, devices, thermal pulsation device treatments, or intense pulsed light. There are a lot of different [management options] being offered.
AJMC®: What could be the value of a treatment for Demodex blepharitis?
JACKSON: If 80% of patients in this Atlas Continuation study said that Demodex blepharitis affected them negatively in their activities of daily living, then a treatment could help improve quality of life for 80% of this population, in general.1 Visual function, such as night driving, was one of the biggest concerns, so [a treatment] could have a big impact.1
Dr Jackson is founder and owner of Jacksoneye.
1. Jackson MA, Yeu E, Matossian C, Kannarr SR, Wesley G, Periman LM. Impact of Demodex blepharitis on patients: results of the Atlas trial. Abstract presented at: 2022 American Society of Cataract and Refractive Surgery Annual Meeting; April 22-26, 2022; Washington, DC. Accessed August 18, 2022. https://ascrs.confex.com/ascrs/22am/meetingapp.cgi/Paper/81946
For other articles and videos in this AJMC® Perspectives publication, please visit “The Evolving Landscape of Demodex Blepharitis Management.”