James Wolffsohn, PhD, PgDip, MBA is Deputy Executive Dean for Life and Health Sciences at Aston University. Paramdeep Singh Bilkhu is a PhD student researching ocular allergy and dry eye disease management at Aston University.
Allergic conjunctivitis is the most common form of ocular allergy, subdivided into seasonal and perennial forms (PAC)1, 2. It is often bilateral, causing symptoms of itchy, irritated, sore and watery eyes1, 2. Signs include conjunctival hyperaemia, chemosis, eyelid swelling and sometimes a mild papillary reaction on the palpebral conjunctiva1, 2. Seasonal allergic conjunctivitis is the most common subtype, and is acute, whereas perennial allergic conjunctivits is chronic in nature but less severe1, 2. The prevalence of allergic conjunctivitis has recently been estimated to be as high as 40%3, and is a common cause of dropout in contact lens wearers4.
Contact lens wearers who develop allergic conjunctivitis are often advised to temporarily cease wear until signs and symptoms resolve, as the allergens may bind to the contact lens surface and prolong exposure5, 6. In addition, traditional topical anti-allergic medications used to treat allergic conjunctivitis require frequent instillation, making contact lens wear impractical6. Patients with existing seasonal allergies are more likely to develop ocular symptoms during contact lens wear7 and the prevalence of allergies is expected to increase, with 50% of Europeans affected by 20158. Hence it is important to examine the scientific literature for evidence-based guidelines to allow patients with allergic conjunctivitis to maintain successful contact lens wear.
Treatment
The primary treatment strategy for ocular allergy is to prevent exposure to the causative allergen(s), which can be identified following a thorough patient history and conjunctival challenge testing9. However, it is often not possible to completely avoid allergens, so anti-allergic medications often become necessary9.
Cold compresses and ocular lubrication with a tear supplement should also reduce symptoms and signs of exposure to the allergen, although the evidence-basis for this is currently weak.
Modern dual action anti-allergic medications combine mast-cell stabilising and antihistaminic properties and require only twice daily dosing. This has made it possible to maintain contact lens wear during an episode of mild to moderate allergic conjunctivitis, as the drug can be applied before the lens is inserted and after it is removed10.
Effects of treatment
Several studies have investigated the effect of these drugs in contact lens wearers with ocular allergy:
- In 2000, Brodsky demonstrated reductions in signs and symptoms of allergy in patients with allergic conjunctivitis due to contact lens wear and patients with seasonal allergic conjunctivitis, vernal conjunctivitis or atopic keratoconjunctivitis following one drop of Patanol twice daily for 28 days11.
- The same research team later showed significantly increased wearing time (on average 2.1 hours longer) and comfort after one drop of Patanol 0.1% in contact lens wearing patients with a history of allergic conjunctivitis compared to placebo using an allergen challenge model12.
More recently, significant increases in total wearing time, comfortable wearing time and improved ocular symptoms in contact lens wearing patients with a history of allergic conjunctivitis was found following use of one drop of epinastine hydrochloride 0.05% twice daily compared to rewetting drops13.
Increasing frequency of lens replacement
Increasing contact lens replacement frequency and initiating strict and careful lens care regimens with preservative-free solutions can help to minimise build-up of allergens and ocular symptoms6, 10. Daily disposables maximise replacement frequency, eliminating the need for solutions, and should be the lens of choice for allergy sufferers.
- In one study, 67% of patients with seasonal allergies reported improved comfort with daily disposables compared to 18% with a new pair of their habitual lenses for one month each during periods where allergen levels were elevated14.
- A significantly greater reduction in conjunctival hyperaemia, corneal staining, and lid roughness from baseline was also found with wear of daily disposables14.
In 2011 two different daily disposables (one with enhanced lubricating agents) were compared to no lens wear in a conjunctival airborne allergen challenge model.
- The severity of burning and stinging were significantly reduced with the lubricating lens, and signs of hyperaemia, ocular surface staining and lid roughness were reduced compared to no lens wear, suggesting a barrier effect to allergen exposure (enhanced by the addition of lubricating agents to the contact lens matrix) rather than prolonging the allergic response15. The duration of symptoms with lens wear was also shorter by 1.7-2.0X compared to no lens wear15.
Based on this evidence, the majority of contact lens wearers with allergic conjunctivitis may continue to wear them successfully. However, lens wear should be ceased when the patient remains symptomatic and or if the cornea is involved, and anti-allergy medication initiated until the signs and symptoms resolve.
REFERENCES
1. Bielory L. Ocular allergy overview. Immunology and Allergy Clinics of North America. 2008;28(1):1-23.
2. Berdy GJ and Berdy SS. Ocular allergic disorders: disease entities and differential diagnoses. Current Allergy and Asthma Reports. 2009;9(4):297-303.
3. Rosario N and Bielory L. Epidemiology of allergic conjunctivitis. Current Opinion in Allergy and Clinical Immunology. 2011;11(5):471-476.
4. Kumar P, Elston R, Black D, Gilhotra S, DeGuzman N, Cambre K. Allergic rhinoconjunctivitis and contact lens intolerance. Contact Lens Association of Ophthalmologists Journal. 2009;17: 31-34.
5. Donshik PC and Ehlers WH. The contact lens patient and ocular allergies. International Ophthalmology Clinics. 1991;31(2):133-145.
6. Lemp MA and Bielory L. Contact lenses and associated anterior segment disorders: dry eye, blepharitis and allergy. Immunology & Allergy Clinics of North America. 2008;28:105-117.
7. Asher MI, Montefort S, Bjorksten B, Lai CKW, Strachan DP, Weiland SK, Williams H. Worldwide time trends in the prevalence of symptoms of asthma, allergic rhinoconjunctivitis, and eczema in childhood: ISAAC Phases One and Three repeat multi-country cross-sectional surveys. The Lancet. 2006;368(9537):733-743.
8. Kari O, Haahtela T. Is atopy a risk factor for the use of contact lenses? Allergy. 1992;47: 295-298.
9. Bielory L. Ocular allergy treatment. Immunology and Allergy Clinics of North America. 2008;28(1):189-224.
10. Lemp MA. Contact lenses and allergy. Current Opinion in Allergy and Clinical Immunology. 2008;8(5):457-460.
11. Brodsky M. Allergic conjunctivitis and contact lenses: experience with olopatadine hydrochloride 0.1% therapy. Acta Ophthalmologica. 2000;78(s230):56-69.
12. Brodsky M, Berger WE, Butrus S, Epstein AB, Irkec M. Evaluation of comfort using olopatadine hydrochloride 0.1% ophthalmic solution in the treatment of allergic conjunctivitis in contact lens wearers compared to placebo using the conjunctival allergen challenge model. Eye & Contact Lens. 2003;29:113-6.
13. Nichols KK, Morris S, Gaddie IB, Evans D. Epinastine 0.05% ophthalmic solution in contact lens wearing subjects with a history of allergic conjunctivitis. Eye & Contact Lens. 2009;35(1):26-31.
14. Hayes VY, Schnider C, Veys J. An evaluation of 1-day disposable contact lens wear in a population of allergy sufferers. Contact Lens and Anterior Eye. 2003;26(2):85-93.
15. Wolffsohn J. and Emberlin JC. Role of contact lenses in relieving ocular allergy. Contact Lens & Anterior Eye. 2011;34(4):169-172.
