Another Study Shows Allergen Immunotherapy Prevents Asthma in Children

from Medscape:

Immunotherapy Prevents Asthma Over Long Term in Children With Allergic Rhinitis
News Author: Will Boggs, MD

August 10, 2007 ― Specific immunotherapy for allergic rhinitis in children prevents the development of asthma for up to 7 years after treatment ends, according to results of a follow-up of the Preventive Allergy Treatment (PAT) study.

The PAT study investigated whether the clinical effects of 3 years of subcutaneous specific immunotherapy persist in children with seasonal allergic rhinoconjunctivitis caused by birch and/or grass pollen allergy as they grow up. The results at 10 years after the start of treatment appear in the August issue of Allergy.

Dr. L. Jacobsen from ALK-Abello, Horsholm, Denmark and colleagues evaluated the primary clinical effect and secondary preventive effect on the development of asthma in 147 participants in the PAT study 7 years after termination of specific immunotherapy.

Among 117 children who were free of asthma at baseline, those treated with SIT were 4.6 times more likely than those treated with placebo to remain free of asthma during the 10 years of follow-up, the authors report.

Specifically, 24 of 53 control patients developed asthma, compared with 16 of 64 patients in the specific immunotherapy group.

The beneficial clinical effect on conjunctivitis and rhinitis following specific immunotherapy also persisted 7 years after completion of 3 years of treatment.

Neither group showed significant bronchial hyperresponsiveness after 5 or 10 years, the investigators say, and there were no differences between the treatment and placebo groups in bronchial responsiveness to methacholine (as measured by change from baseline).

“This 10-year follow-up study demonstrates that specific immunotherapy for 3 years with high-dose standardized allergen extracts shows persistent long-term effect on clinical symptoms after termination of treatment and long term, preventive effect on later development of asthma in children with seasonal rhinoconjunctivitis,” Dr. Jacobsen and colleagues conclude.

“In this light,” they write, “specific immunotherapy should be recognized not only as first line therapeutic treatment for allergic rhinoconjunctivitis but also as secondary preventive treatment for respiratory allergic disease.”

Allergy. 2007;62:943-948.

Reuters Health Information 2007. © 2007 Reuters Ltd.

Doctors’Dilemma: Caught Between Patients and Insurers

JC is an active, 50 plus year old male who was gardening outdoors when he was stung by a yellow jacket. Within 15 minutes, he got dizzy and collapsed. His family called EMS and the paramedics arrived 5 minutes later and injected him with epinephrine and started IV fluids. He was transported to the nearest ER where he got more IV fluids, steroids, and Benadryl. He was observed in the hospital overnight and discharged with an epinephrine autoinjector and a referral to the local allergist. He saw the allergist and one month later was found to be allergic to yellow jacket, wasp, and hornet venom and started venom allergy injections which would protect JC from any further episodes of anaphylaxis for the rest of his life.

A simple happy ending, right? Wrong! Unfortunately, medical care in this country is no longer that simple or straightforward. For some reason only known to itself, JC’s insurer decides to cut payments for venom allergy injections down to half of acquisition cost (meaning half the price of buying the venom from the manufacturer, not even including the price of needles, syringes, alcohol pads, and the nurse giving the injection). Calls are made and letters are written to medical directors, without avail. This now puts JC’s doctor in a bind:

How can you continue providing a service or a product when you are losing money on that service/ product?

The answer is, you can’t. Bakers stop making cakes, carmakers stop making cars, shops close down. And yet, this is not just a cake, or a car, or a shop. This is JC’s health and life.

JC’s insurer is playing games with patients’ health care. It doesn’t want to get the rap for not covering a very important therapeutic intervention, BUT it doesn’t want to pay for it either. So, who gets left holding the bag? JC’s doctor, for now. But since you can’t continue practicing at a loss, eventually JC and all the other patients will not have access to this therapy, even as they religiously pay their insurance premiums every month. This scenario is seen in slightly different settings all over the country, from chemotherapy and vaccinations, to mental health services.

Patients deserve good health care and doctors should not be penalized for practicing good medicine. Insurers should be helping patients and physicians, not making it more difficult. Stop playing games, or we all lose.

Clarifying Misconceptions About Allergen Immunotherapy

I was recently embroiled in an online discussion with several pulmonary and primary care colleagues regarding the efficacy of Allergen Immunotherapy in the treatment of asthma and the future of sublingual immunotherapy, which I think is worth sharing. Let’s start off with some Frequently Asked Questions:
Whare are “Allergy Shots”?
Allergen immunotherapy or “allergy shots” is a form of treatment aimed at decreasing sensitivity to substances called allergens which were identified by allergy testing. Allergen immunotherapy involves injecting increasing amounts of these allergens to a patient over a period of time to decrease the patient’s sensitivity to the allergens, prevent development of new allergies, and in children, prevent progression from allergic rhinitis to asthma. Allergen immunotherapy can lead to long-lasting relief of allergy symptoms after treatment is discontinued.

How does Allergen Immunotherapy work?
Allergen immunotherapy works like a vaccine. Your body responds to injected amounts of a specific allergen by developing immunity or tolerance. There are two phases to immunotherapy: a build-up phase and a maintenance phase.

When will the allergy shots start working and when can I stop my meds?
The benefits of allergen immunotherapy, in terms of reduced allergy symptoms, can begin during the build-up phase but may take as long as 12 months on the maintenance doses. It is important to continue taking allergy medications as prescribed together with the allergy shots during the build-up phase. Later, when your symptoms improve, you may discuss with your doctor whether you can discontinue some of your allergy medications.
If you do not get your allergy shots on schedule, it will take longer to reach the maintenance dose and longer for the allergy shots to work effectively.

How long do I have to take the Allergy shots?
With currently available allergen extracts, maintenance treatment is generally continued for 3 to 5 years after the build-up phase, which can take up to 6 to 9 months. The majority of inidividuals experience lasting remission but a minority may relapse after discontinuing immunotherapy, therefore the decision to stop must be individualized.

How effective is allergen immunotherapy?
Immunotherapy is successful in up to 90-95% of patients with seasonal allergies and up to 85% of patients with year-round allergies.

Asthma is a multifactorial disease. Allergic rhinitis/ sinusitis has definitively been shown to contribute to the severity of asthma in patients. One of the modalities used to treat allergic rhinitis/ sinusitis and asthma is allergen immunotherapy (IT). By no means is anyone suggesting that allergen immunotherapy be used INSTEAD OF inhaled steroids, however allergen IT does have solid data to show its efficacy when used in conjunction with other modalities.

This is topic has been addressed by the American College of Allergy, Asthma, and Immunology in its position paper on the Cost Effectiveness of Immunotherapy for Asthma.

Regarding sublingual immunotherapy, there is considerable evidence that sublingual immunotherapy for allergic rhino-conjunctivitis has been effective using high doses of grass extract. This is commercially available and used in Europe, but has yet to have FDA approval in the USA. Some studies showing efficacy are cited below:
1. Calderon M, Essendrop M. Specific immunotherapy with high dose SO standardized grass allergen tablets was safe and well tolerated. J Investig Allergol Clin Immunol. 2006;16(6):338-44. 2. Nelson HS. Advances in upper airway diseases and allergen immunotherapy. J Allergy Clin Immunol. 2007 Feb 8; [Epub ahead of print]
That being said, appropriate dosing and efficacy with multiple SL allergen combinations are still an issue.

The “sublingual immunotherapy” that is pure quackery has been used to treat “idiopathic environmental intolerance” (IEI) by means of “neutralizing” extracts administered as sublingual drops usually at such a miniscule dose that it is really only placebo. See the AAAAI position statement on this.

For a tragic example of the use of these “neutralizing sublingual drops” for treatment of IEI or “multiple chemical sensitivity syndrome” see the “Tragic Example” post on this blog.

Link: Allergen Immunotherapy Practice Parameters
AAAI Tips to Remember: What are Allergy Shots?
Table: Clinical Indications for Allergen Immunotherapy