Do people who have anaphylactic reactions to insect stings or foods have specific forms of genes for hormones involved in controlling blood pressure?

ISRCTN ISRCTN10465389
DOI https://doi.org/10.1186/ISRCTN10465389
Secondary identifying numbers vv14/97
Submission date
26/01/2019
Registration date
13/02/2019
Last edited
15/02/2019
Recruitment status
No longer recruiting
Overall study status
Completed
Condition category
Injury, Occupational Diseases, Poisoning
Prospectively registered
Protocol
Statistical analysis plan
Results
Individual participant data

Plain English summary of protocol

Background and study aims
Shock is when there is not enough blood flow to the tissues of the body. When a person has anaphylaxis (a serious allergic reaction), high levels of a chemical called histamine are released. Histamine causes blood vessels to dilate (open up). This causes blood pressure to drop and can lead to anaphylactic shock. It has previously been shown that the severity of anaphylactic shock in people who are allergic to bee or wasp stings is linked to low levels of hormones in the blood that control blood pressure. However, there is currently no evidence of whether this is also true in people with food allergies. This research team has already done some analysis of the genes for these hormones in people with food allergies. This study aims to compare the genes for blood pressure hormones in people with no allergies, people with allergies to airborne allergens (for example, pollen) but not food, people with allergies to bee or wasp stings who have had anaphylactic reactions, people with food allergies who have never had an anaphylactic reaction and people with food allergies who have anaphylactic reactions.

Who can participate?
People with no allergies, people with allergies to airborne allergens (for example, pollen) but not food, people with allergies to bee or wasp stings who have had anaphylactic reactions, people with food allergies who have never had an anaphylactic reaction and people with food allergies who have anaphylactic reactions. Participants must not be taking some medicines that affect blood pressure.

What does the study involve?
The participants will have a sample of blood taken in the morning before they eat. The blood will be used to prepare a sample of DNA, which will be analysed to show which forms of the blood pressure-controlling genes the person has. The details of their allergies and anaphylactic reactions will be taken from their medical records.

What are the possible benefits and risks of participating?
There is no direct benefit to the participants. The potential risks relate to discomfort from the blood-taking.

Where is the study run from?
St Helier Hospital, Carshalton (UK)

When is the study starting and how long is it expected to run for?
April 1997 to January 2012

Who is funding the study?
Epsom and St Helier Hospitals NHS Trust (UK)

Who is the main contact?
Dr Veronica Varney, veronica.varney@btinternet.com

Contact information

Dr Veronica Varney
Scientific

Allergy Clinic
St Helier Hospital
Wrythe Lane
Carshalton
SM5 1AA
United Kingdom

ORCiD logo 0000-0001-7531-6139
02082962401
veronica.varney@btinternet.com

Study information

Study designObservational cross-sectional study
Primary study designObservational
Secondary study designCross sectional study
Study setting(s)Hospital
Study typeOther
Participant information sheet ISRCTN10465389_PIS.docx
Scientific titleHymenoptera venom anaphylaxis and food allergy induced anaphylaxis: A study of the renin and angiotensin system
Study objectivesIn 1993, Hermann and Ring demonstrated that the severity of anaphylactic shock following bee or wasp stings was linked to low levels of renin and angiotensin 1 and II in the blood permitting hypotension. To date, no published studies have examined this in subjects with food-induced anaphylaxis. Our preliminary data from this study collected in 1998 has shown that 85% of subjects with anaphylaxis to food had low levels of serum ACE and were homozygous (II genotype) or heterozygous (ID genotype) for the angiotensin gene deletion. This deletion results in low activity of angiotensin converting enzymes and reduced angiotensin II production compared with homozygous gene state (DD) that is associated with high levels of production.
Ethics approval(s)1. Approved 04/04/1997.
2. Re-approved 05/08/2005, London-Surrey borders Ethics Committee (Usual meeting venue
Health Research Authority, Skipton House, 80 London Road, London, SE1 6LH; +44 (0)20 7972 2568; NRESCommittee.London-SurreyBorders@nhs.net), ref: 14/97
Health condition(s) or problem(s) studiedAnaphylactic shock
InterventionThe study will be based on patients normally referred to the Allergy Clinic at St Helier Hospital. From their outpatient attendance and assessment, suitable patients will be selected and asked to make a single attendance before breakfast on a single occasion. Five groups of patients will be selected (non-atopic, airborne allergy only, food allergies, food allergy with anaphylaxis, bee and wasp allergy).

In each patient a single visit on a Saturday morning before breakfast is required. The patient must lie horizontal for 20 minutes. After this time blood will be taken at 4ºC and spun immediately in a refrigerated centrifuge and stored. The patient may then eat and drink and apart from details of the anaphylaxis and timing and results of skin tests no further visits are required. Most of the information can be collected onto a short questionnaire directly from the notes. The patients will be selected following their assessment in the allergy clinic
Intervention typeOther
Primary outcome measure1. Serum ACE level
2. Plasma renin level
3. Plasma angiotensin-1 level
4. Polymorphisms of genes related to the renin angiotensin system including ACE, renin, angiotensinogen (AGT235), chymase CMI-1903, AT-2 receptor
Secondary outcome measuresN/A
Overall study start date04/04/1997
Completion date01/01/2012

Eligibility

Participant type(s)Patient
Age groupAdult
SexBoth
Target number of participantsWasp and bee induced anaphylaxis (>50), food induced allergy without anaphylaxis (>50), food allergy without anaphylaxis (>30), atopic without food allergies (>30), non-atopic control (>100)
Key inclusion criteriaAnaphylaxis patients:
1. Wasp- and bee-induced anaphylaxis (>50) or food-induced allergy with anaphylaxis (>50)

Control participants:
2. Food allergy without anaphylaxis (>30) or atopic without food allergies (>30) or non-atopic control (>100)
Key exclusion criteria1. Pregnant
2. Taking drugs that would affect the renin-angiotensin system and levels of blood hormones
3. Involved in any other studies which would be either disadvantageous to the participant's health or the benefit of the study
Date of first enrolment05/04/1997
Date of final enrolment06/08/2008

Locations

Countries of recruitment

  • England
  • United Kingdom

Study participating centre

St Helier Hospital
Wrythe Lane
Carshalton
SM5 1AA
United Kingdom

Sponsor information

Funders

Funder type

Hospital/treatment centre

Epsom and St Helier Hospitals NHS Trust

No information available

Results and Publications

Intention to publish date01/03/2019
Individual participant data (IPD) Intention to shareYes
IPD sharing plan summaryOther
Publication and dissemination planResults were published in 2012. A further paper (Bi-allelic and tri-allelic gene combinations of ACE, Angiotensinogen and Chymase and their association with IgE mediated systemic anaphylaxis) is ready for submission.
IPD sharing planThe datasets generated and/or analysed during the current study during this study will be included in the subsequent results publication.

Study outputs

Output type Details Date created Date added Peer reviewed? Patient-facing?
Results article results 19/12/2012 28/01/2019 Yes No
Participant information sheet 15/02/2019 No Yes

Additional files

ISRCTN10465389_PIS.docx
Uploaded 15/02/2019

Editorial Notes

15/02/2019: The participant information sheet has been uploaded.

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