GA2LEN SURVEY FOLLOW UP STUDY

It is increasingly clear that Europe is experiencing an epidemic of allergic
disease and that this epidemic is spreading rapidly into the older population.
Analysis of birth cohort data have shown that the prevalence of sensitisation
to allergen does not decline with age, as was once thought, and that succeeding
generations * at least up until those born around 1970 * have an increasing
prevalence of allergic sensitisation.

European research has achieved much from co-ordinated efforts to investigate
the distribution of atopic disease and its risk factors across the broad
environment of Europe. Studies have included cross-sectional and longitudinal
designs and have studied children and adults and special groups. There are
nevertheless major gaps in knowledge that need to be filled. These gaps include
population groups, disease groups and risk factors. There are also questions
raised by earlier studies that require answers.

Review of the progress within the GA²LEN network by external experts identified
the need to bring more coherence to the work of the network and to devise
common programmes that could bring together the efforts of the different
groups. This matched with the views of the work package leaders who had
identified a number of projects that might be able to focus work in different
areas. Further discussion narrowed these proposals to a cross-sectional survey
based on the current partners and any other centres that wished to join in.

To assess
1. the burden of allergic disease across Europe*s aging population
2. the association of severe asthma with potential risk factors and their
impact on lung function decline over time
3. the association of asthma severity with sex hormone levels particularly in
women after the menopause
4. the association of asthma severity and chronic sinusitis with production of
IgE to S. aureus in the general population
5. the association of asthma and atopic conditions of interest with dietary
patterns in the general population
6. the association of asthma and other atopic conditions with occupational
exposure to cleaning agents and the clinical environment

To set up a platform for further research in allergy and asthma

The follow-up study will be a nested case control study among those responding
to the GA2LEN survey that have indicated that they are willing to be
re-contacted.

Subjects will be invited in for an examination and tests that will take
approximately two hours.

Prior to the interview the subjects will be sent a food frequency questionnaire
which will be checked at the interview. Other questionnaires will be
administered at the visit and these will collect information on symptoms and
diagnoses (RSOM-31), use of health care, smoking and passive smoking,
occupational exposures, and functional quality of life (SF-12).

The other tests which will be undertaken at the visit will include:

1. Spirometry before and after 200 microgr. salbutamol
2. Peak nasal inspiratory flow
3. Smell test
4. Height, weight and waist/hip circumferences
5. Skin prick tests for a standard set of allergens standardised for the GA2LEN
network
6. Blood will be drawn and
* serum will be taken to measure total IgE, specific IgE to Timothy Grass , S
aureus superantigens and sex hormones
* whole blood will be stored for DNA analysis
7. Examination by the use of a nasendoscope

All serology will be undertaken in a single centralised laboratory with strict
quality assurance (Amsterdam).

Possible disadvantages and risks of taking part.
Blood collection from an arm vein can sometimes cause some temporary discomfort
and can occasionally result in minor local bruising.

Skin prick tests on the forearm do not tend to cause any discomfort other than
wheals similar to nettle rash if you have a positive result. These may last
for up to an hour. In very rare occasions an analphylactic reaction can occur,
which will treated in an adequate way (adrenalin and resuscitation equipment).

Lung function tests are a routine hospital investigation. They involve blowing
into a machine and can be quite hard work * but not uncomfortable.
The lung function tests are safe, but on principle we will not include you in
the study if:
* You have had a heart attack in the last three months
* You have had cataract surgery or a major surgical procedure in the past one
month
* You are a woman in the last trimester of pregnancy
* You are taking medication for tuberculosis
* You have any other illness (such as unstable angina or a chest infection)
that, in the opinion of the researchers, may affect your ability to do the test
safely.

Possible benefits of taking part.
There will be no immediate benefits for the person who agrees to help with this
study, apart from finding out about his or hers allergic status and lung
function.