A true opt out is the right to not participate at all meaning no questionnaire, no nothing. How they end up qualifying and quantifying the questionnaire-only and true opt out would be how I would need to come at it. I appreciate as a subject you would like to provide information but two things. 1. For me to try to tinker with someone else's subject is a low blow I'd prefer not to 2. It's how the data and data like this will be presented ultimately, concluded and used that is my concern, in other words during the peer review portion of the process.

If the subjects are controlling the experiment something is extremely borked. The only thing under subject control is participation. Additionally there should be noted the difference between exclusion and opting out. Exclusion one has no control over and it will never be directly included with the data. I should also note that although I realize this is a study it feels a little more on the experimental side to me. In the way that a challenge isn't really a study as gold standard is double-blind. This one is merely open.

Will have to take time to read through the last few posts.

As part of this study, there is a questionnaire for those who are invited to participate but opt out. I'd imagine there are families who have similar concerns as those addressed in this thread and are not comfortable allowing their child to eat a dose of peanut. Per the abstract, the questionnaire is a "a set of questions intended to permit comparison of basic demographic and clinical allergy data in those choosing not to participate and in study participants."

I'd be satisfied if there was some platform for a consumer driven counterpoint to include the self-represented voice of those at higher/highest risk threshold throughout study and legislation. It's a little disturbing to have a horrible double-whammy of low transparency and zero representation where these decisions are being made in our stead with increasingly diminishing recourse.

The Taylor reference in that link is particularly interesting/telling-- because these values are based upon those patients who are deemed a safe-enough risk to challenge.

What of those whose reaction history is suggestive of not being safe to challenge?  Individual patient risk-benefit plays a role in these studies, and automatically limits who participates if you're doing informed consent.  (Which any reputable study MUST do.)  Catch-22, that.

Literature over the past 20 years seems to strongly suggest that there are some serious structural problems with conclusions in that link; the eliciting doses indicated in the table are really bass-ackwards given what clinicians know/suspect-- and what patients report being the case re: thresholds that are typical. 

XC reactions that are life-threatening seem to be reported most frequently from peanut, cashew, and sesame, for one thing-- and the few studies that have attempted to tease apart a lower eliciting dose can't seem to go low enough with those three.  It makes no sense to me that egg would be an order of magnitude LOWER than peanut there.

So why is it that most people with egg allergy seem to tolerate cleaned lines quite well-- and so many with peanut allergy do not? Is it heat lability of the allergen?  I seriously do not know.  But it DOES seem crazy to me that the thresholds for those three allergens in particular are that low.  So wheat needs a lower threshold than pn?  Really??    I mean-- hey, maybe it does-- but I'd be shocked if that were borne out by a full population analysis of that group.  It suggests that those who react to ultra-trace amounts of WHEAT are more "usual" among those with that allergy than they are among peanut-allergic patients. 



I mean, these aren't necessarily formal criticisms of that data-- but they are disquieting to me personally in that when a data set doesn't seem to match broad anecdote, I have to wonder what the heck is up with that. 

We all want to read this. All credit to Links being on top of it, very much obliged.

I'm sorta wondering in which journal they're aiming to publish in assuming of course the goal is to publish for peer review. At least it could provide some insight where they're going with it. Unless this is more a private side deal. I'm also worried about it being a one-off in the sense that IRB won't sign off on many threshold investigations for obvious ethical concerns.

In other words highly filtered and controlled sample becomes entire population which becomes "truth" because we have primitive math modeling to prove it. This does have me biting my nails a bit for the future of labeling laws.

I could be totally wrong here, but I am curious if the results will influence VITAL (the authors seem to have a lot of Australian connections).

http://www.allergenbureau.net/vital/vital

QuoteThe VSEP is a collaboration between the Allergen Bureau, Food Allergy Research & Resource Program (FARRP) of the University of Nebraska & the Netherlands Organisation for Applied Scientific Research (TNO).

The study could impact advisory labeling.

The thing about FARRP is I keep seeing them push for less labeling.

For example:

sesame seed study.

Survey on Thresholds from FARE (page 4)

http://allergy.hyperboards.com/action/view_topic/topic_id/17461

----------------

New exemptions from Food Allergen Labeling

http://www.regulations.gov/contentStreamer?objectId=090000648121e481&disposition=attachment&contentType=pdf
page 130 & 154

Speaking for myself my questions would actually not be for the test subjects but the researchers. My only concern for test subjects directly would be limited to making sure all human subjects received all due ethical consideration owed to each and every one. And that is the responsibility of the IRB, not me.

Now the ultimate plan on the data use and strategy behind the criteria, especially if there will be some suggestion to correlation through population. Previous stated issues on primitive math modeling in another thread. Depends on what is going to be done with it, their conclusions.

Well, selfishly (since I know you) I'm hoping that your son's RAST is the result of some quirky thing, and that he passes his challenge.   

If that happens, though-- will he still be counted "allergic" for the purposes of the study?

What exactly constitutes a "pass" or a "fail" in the challenge itself?

I'm wondering what they consider to be a normal tolerance.

Quote from: CMdeux on December 14, 2013, 11:08:33 AM
Doc doesn't think component testing will tell us much as DS does not have environmental allergies.

I'm not sure that I understand the reasoning here-- is this because some components are more associated with OAS and pollen-cross-sensitization than others?

Yes some components are associated with cross-sensitivity,  to birch tree pollen, I believe. Given my son has no environmental allergies he should test negative to those components.

Inclusion criteria
Each patient must meet all of the following criteria to be enrolled in this study.
• Age between 1 to 18 years old and
• Demonstrate evidence of peanut allergy as defined by either
(a) History of unequivocal exposure (including accidental) and typical acute
allergic reaction within the preceding 2 years and positive peanut SPT/sIgE, or
(b) Positive oral food challenge with peanut performed within 2 years - either
open oral food challenge or DBPCFC (Double-blind, placebo-controlled food challenges)
(c) Peanut never ingested, but sensitisation to peanut above the 95% positive predictive value (PPV) for clinical allergy, i.e. peanut serum IgE ≥ to 15 kU/L (by CAP FEIA) and/or peanut SPT wheal size ≥ to 8 mm within 2 months of the single dose challenge.


DS meets the criteria based upon (c) above.

He had reactions via breastmilk. He has also had contact reactions of which we were not able to determine origin. Daycare provider served and herself ate dairy, eggs and peanuts while caring for DS when the reactions occured. This happened on a few occasions after which we pulled him from daycare.

Your point about whether or not it is fair to include him as peanut allergic in this study goes along with what has been mentioned in this whole thread. That's why I asked "any questions to ask."

Doc doesn't think component testing will tell us much as DS does not have environmental allergies.

I'm not sure that I understand the reasoning here-- is this because some components are more associated with OAS and pollen-cross-sensitization than others?

I'm with you-- given the possibility that reaction history is NOT to peanut at all, I'd think that component testing and a possible challenge are a great idea and possibly a good source of information for you.


I'm also a little confused-- without INGESTION history supporting diagnosis of peanut allergy, is it fair to call your child "allergic" for the purposes of the study?

It seems like that could result in inclusion of any number of patients who are not actually peanut allergic.  What am I missing? 

My son is participating in this study. We have agreed to participate based upon some things that were brought up in this thread - IgE >100 but no known ingestion; has had possible contact or airborne reactions but weren't able to determine if it was from dairy, eggs or peanuts as.

Study consists of the challenge and component blood testing, as well as surveys filled out by myself and DS. Doc doesn't think component testing will tell us much as DS does not have environmental allergies. I feel it would mean a lot to us if he tests low/negative to the proteins that are indicators that anaphylaxis is likely to occur upon ingestion. If that is the case, we will likely ask for an actual peanut challenge. He has challenged dairy with known past anaphylaxis and IgE of >100, so we might be the exception to the rule of not wanting to participate a study on thresholds when one has experienced prior anaphylaxis.

Any specific questions you'd like me to ask?

I react to airborne peanut so I would never participate in any ingestion study... not even 1.5 mg.   And I would never let me daughters participate either (we've been to the emergency room too many times)

The criteria look exactly the same as the criteria for the study we did. FEV1 <80% just means asthma must be well-controlled. They're not saying you can't be on antihistamines - just that you have to be willing and able to discontinue them before challenges.

They had two kids in my son's study who discovered they didn't HAVE a peanut allergy during the first challenge. The doctors and nurses were so happy about those - I'm sure they love including kids who have no real history. The proof is (literally) in the pudding, so I don't know why it matters if they include kids who have never had a reaction. They can't count them in the study results if they don't have an initial reaction. I'm sure they're doing everything they can to dig up participants.