Avoidance in allergy: To be avoided?

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The world of allergy is changing quickly; more than ever dogma is challenged in the light of scientific evidence.  In respiratory allergy, the old reflex of systemically recommending eviction may be worth revisiting.  This year’s most anticipated allergy study, one on peanut allergy, clearly brings a new dimension to the discussion.

Allergy in school

Should we change our approach of strict allergen avoidance in the school environment?  Marie Allard, an excellent journalist, was courageously raising the question in her article published in La Presse last October 13th.  Difficult issues are looked at from the perspective of the various stakeholders.  Clearly evident is a desire to define the best, most reasonable approach in the respect of all.

Peanuts: The earlier the better!

Dr. Gideon Lack has without a doubt become a star of the allergy world with the publication from his group, the LEAP study, that documents a marked increase in the risk of children developing peanut allergy if its introduction is delayed and its consumption minimized.  In fact, during his presentation at this year’s EAACI (European Academy of Allery and Clinical Immunology) annual meeting in Barcelona last June, Dr. Lack went as far as to refer to the parents being able to “prevent” peanut allergy in their children by introducing it early in suitable form (prophylactic treatment).  Parents should be encouraged to introduce peanuts (probably in the form of peanut butter) early on, even at 4 to 6 months of age and have it consumed regularly thereafter.

Respiratory allergies: The mirage of avoidance

We all recognize that avoidance of allergens, in the short term may help control symptoms such as sneezing, nasal congestion, itchy eyes or those of asthma. Conceptually however, an unequivocal recommendation of allergen avoidance in respiratory allergy does not make the best of sense……even if it is a common practice and here is why:

Allergies in an artificial world

It is now becoming clear, the cause of allergies relates to our living in a world each day more artificial, too clean biologically, too polluted, too stressful and where too much sugar and antibiotics are consumed.  In a sense, the avoidance of respiratory allergen, a measure which we hope can help allergy symptoms in the short term, only confines the allergic person to an even more artificial world deprived of pollens, house dust mite and cat-related proteins.  That is what our videos were making fun of last year (cat, house dust mites, and seasonal pollens).  By encouraging strict avoidance, are we not in effect enforcing the dynamics that originally led to the development of respiratory allergies?

Immunotherapy: the most “natural” treatment of respiratory allergies

In a sense, immunotherapy manages to reintroduce some natural proteins into our lives.  In another sense, the proponents of “natural medicine” cannot find a more natural remedy than extract-based immunotherapy.  Those products convey in a most natural form the very proteins of common respiratory allergens (cat, pollens or house dust mites) in a glycerin solution that preserves these proteins. 

Eviction: a treatment of allergy, buying time or flight forward?

The established dogma remains to treat respiratory allergies via avoidance and the treatment of symptoms with medications (antihistamines, topical nasal steroids for the nose, eye drops, saline nasal douches and various medications for asthma).

Certainly it can be quicker to tell patients to avoid outdoor activities during pollen season or to recommend house dust mite impermeable mattress and pillow covers.  In reality, however, the scientific proof for the efficacy of these measures is rather poor.  Indeed, allergen avoidance can help the control of allergy symptoms in the short term and sometimes there is no other way around it (for example in a two-year-old child allergic to cats).  But in other situations, are we not only avoiding the real treatment of allergy?  To limit our therapeutic intervention to the mere control of symptoms grants more time for one’s allergic disease to move ahead causing further allergies, asthma and complications, some of which doctors are only now being able to discern the extent of (eosinophilic esophagitis, for example).

Frequently we are told by patients that they have grown in the presence of a cat without much in the way of symptoms, only to find out that after a period of their being away (for studies or work) that they are suddenly severely sick even with modest exposure to cats.  They have simply lost their tolerance for the cat allergen.  Should we add to the advice “get rid of the cat” the following warning:
“…….and by the way, if you are ever exposed to cats again, your symptoms might  be a lot worse”.

Allergic living: Not that simple…..

The credibility of our specialty can only be enhanced by our demonstrating due empathy for the significant emotions people may have for their pets.  To this significant contribution to a fulfilling emotional life, the role of pets may also be even more crucial for vulnerable patient groups (patients with blindness or behavior difficulties, for example, where an animal can make all the difference). And what can we say about all those new couples where dander allergy of one of the partners becomes a serious issue?

Immunotherapy, as a first line treatment?

Some european leaders in the field of allergy are proposing the consideration of immunotherapy as first line treatment for some cases of respiratory allergies. The physician’s role is to help people within their reality, to guide them through the choices that medicine can offer within the present means.  In this sense, immunotherapy, which could only be provided in the past through injections, had a modest role, limited by risks and the inconvenience of repetitive visits over long periods of time. That may explain their relatively limited use, essentially as a last resort measure for some determined individuals affected by respiratory allergies.

But now sublingual immunotherapy, easier and safer and generally as effective, allows us to reconsider the options that we can present to our patients.  Hence, for those where getting rid of the pet is out of the question, there are now new treatment options to be considered, to be adjusted according to individual circumstances (asthma in particular and other disease, the use of certain medications, among them Beta blockers, etc.) 

Discussing immunotherapy takes time…

Indeed discussing the pros and cons of immunotherapy while taking into consideration the patient’s individual circumstances takes time.  Neither North American patients nor practitioners are really used to this form of immunotherapy yet.  I am always amazed at how much more intuitive it seems to be for me to go through this explanation with my patients from Europe where sublingual immunotherapy is customary.  Establishing teaching routines and clinical protocols represents a significant change and remuneration for this in North America is generally not yet adapted.

Thus, in general, the adoption of sublingual immunotherapy remains rather timid…

Newer immunotherapy alternatives

Within the next few years, new formulations of immunotherapy, some in the form of a limited number of injections (four to seven) over a few months with focused preparations developed on the basis of genetic engineering will come to the market.

From the scientific standpoint, environmental avoidance often gives limited results in respiratory allergies.  It is only at the level of food allergies that strict avoidance is necessary for one or many food items and even there one can hope that the situation might change over the next generation or two.

As to the symptomatic treatment of respiratory allergies, it is certainly and justified on an acute basis but the very need to resort to such should raise a concern regarding a more chronic disease often of an evolving nature.  For the most part the treatment of respiratory allergy symptoms, while helping in the short term, runs the risk of masking the problem.  Each patient’s case is unique; we must be able to distinguish the clinical subtleties of each and in this sense, a consultation with a specialist versed in allergy will be in the best position to review with you every option.

Patients with respiratory allergies need to hear a different message. They must understand a new paradigm of allergy care where tackling the condition earlier opens better treatment options.