What 2012 allergen avoidance

WHAT YOU SHOULD HAVE READ BUT….2012

 allergen avoidance

Attilio Boner
University of
Verona, Italy

Prevention of asthma in genetically susceptible
children: A multifaceted intervention trial focussed
on feasibility in general practice
Maas Pediat Allergy Immunol 2011;22:794
1) The only variables that seemed to
influence the development of asthma
 Simultaneous reduction were number of weeks a child was
in the environmental breast-fed and the exposure to the
exposures to inhalant- house dust mite allergen Der p1
and food allergens. above or below the group median
(0.6606 μg/g of dust).
 476 children susceptible
2) Breast-feeding seems to
for developing asthma. significantly reduce the development
of asthma (p=0.026), whereas a
 Diagnosis of allergic Der p1 exposure level at 4 yr of
asthma at age 6 yrs. age below the group median may
indicate a protective effect
(p = 0.061).

Prevention of asthma in genetically susceptible
children: A multifaceted intervention trial focussed
on feasibility in general practice
Maas Pediat Allergy Immunol 2011;22:794

OR for allergic asthma
2.0 –
 Simultaneous reduction at age 6 years
in the environmental
exposures to inhalant-
1.70
1.5 –

and food allergens.
1.0 –
 476 children susceptible
for developing asthma.
0.5 –

 Diagnosis of allergic
asthma at age 6 yrs. 0
0.25
Der p1 >0.66 Breast-feeding
μ/g of dust 12-25 weeks vs 0

Opposite effects of allergy prevention depending
on CD14 rs2569190 genotype in 3 intervention
Studies Kerkhof JACI 2012;129:258

• The Dutch Prevention and Incidence of Asthma and Mite Allergy
(PIAMA) study investigated whether the use of mite
allergen–impermeable mattress covers (IMCs) reduced
the risk of asthma and allergy in high-risk children.

No effect was found, despite lower allergen levels
on the children’s mattresses.
In the winters of 1995/1996 and 1996/1997, which
but preceded and coincided with the PIAMA baseline
measurements, temperatures had been extremely
La mano de DIOS...was the PIAMA low, and precipitation had been extremely low as
intervention study intervened upon? well. It is likely that these unusual winter weather
Brunekreef B, Allergy. 2005;60:1083-6. conditions affected the baseline allergen levels in
the PIAMA study so that the effect of the planned
intervention (mite impermeable mattress covers)
was considerably smaller than it could have been.

• Dutch Prevention of Asthma in Children (PREVASC) study and
Canadian Childhood Asthma Primary Prevention Study (CAPPS)
assessed the effectiveness of a multifaceted intervention program
for primary prevention of asthma in high-risk children, including
the use of mattress covers.
• A meta-analysis of the PREVASC study, CAPPS, and the
Isle of Wight study showed a decreased risk of asthma with
multifaceted interventions in the first 5 years of life.
Although this effect was still observed in CAPPS at 7 years of
age, the prevalence of atopy was not reduced.
1. Corver K,, et al. House dust mite allergen reduction and allergy at 4 yr: follow up of the PIAMAstudy. Pediatr Allergy Immunol
2006;17:329-36.
2. Chan-Yeung M, et al. The Canadian Childhood Asthma Primary Prevention Study: outcomes at 7 years of age. J Allergy Clin Immunol
2005;116:49-55.
3. Woodcock A, et al. Early life environmental control: effect on symptoms, sensitization, and lung function at age 3 years. Am J Respir
Crit Care Med 2004;170:433-9.


• A possible explanation might be that the interventions
simultaneously reduced microbial exposure in the
children’s mattresses, which are important reservoirs
of bacteria and microbial products.

• This would support the hypothesis that binding of
microbial antigens to innate immune receptors skews
the immune system toward a TH1 response, favoring a
nonallergic immune response.


• A common functional single
nucleotide polymorphism in the
innate receptor CD14 (rs2569190)
has been shown to interact with the
level of microbial exposure in the
development of atopy.

• Therefore we studied whether the
rs2569190 genotype modifies the
intervention effects on the
development of asthma and allergy in
the PIAMA, CAPPS, and PREVASC
birth cohoorts.


Intervention measures
aimed at preventing
 CC/CT versus the development of atopy by
TT genotype reducing the amount of exposure
of rs2569190. to inhalant allergens
in high-risk children might have
 Outcomes were opposite effects in subgroups of
measured at children with specific CD14
ages 8. genotypes, possibly because of the
simultaneous reduction of exposure
to microbial products.


What will be Intervention measures
aimed at preventing
 CC/CT effect of
the versus
the development of atopy by
allergen
TT genotype reducing the amount of exposure
avoidance
of rs2569190. to inhalant allergens
togheter with in high-risk children might have
 Outcomes were
the simultanaous opposite effects in subgroups of
measured at children with specific CD14
administration of
ages 8. genotypes, possibly because of the
bacterial
simultaneous reduction of exposure
products? to microbial products.

Effect of freezing, hot tumble drying and washing
with eucalyptus oil on house dust mites in soft toys
Chang Pediat Allergy Immunol 2011;22:638

% reduction in living mites
 36 toys (12 in each Freezing Hot tumble Washing with
treatment group). drying eucalyptus oil
90
 Live HDM by the 10 –
heat escape method 20 –
4.25
before and after 30 –
freezing 40 –
overnight, hot 50 –
tumble drying for 60 –
1 h and washing in 70 –
0.2% to 0.4% 80 –
-95% -89% -95%
eucalyptus oil. 90 –
100 –

Effect of freezing, hot tumble drying and washing
with eucalyptus oil on house dust mites in soft toys
Chang Pediat Allergy Immunol 2011;22:638

% reduction in living mites
 36 toys (12 in each Freezing Hot tumble Washing with
Additionally, washing
treatment group). drying eucalyptus oil
with eucalyptus oil 90
 Live HDM by the a
resulted in 10 –
heat escape method
significant reduction 20 –
4.25
before and after as
in HDM allergens 30 –
freezing a geometric
well from 40 –
overnight, hot μg/g
mean of 9.12 50 –
tumble drying μg/g
to 0.37 for 60 –
(p = 0.033).
1 h and washing in 70 –
0.2% to 0.4% 80 –
-95% -89% -95%
eucalyptus oil. 90 –
100 –

Nocturnal temperature controlled laminar airflow for
treating atopic asthma: a randomized controlled trial
Boyle, Thorax 2012;67:215

Background:
• In patients with atopic asthma, the abnormal immune response
to inhalant allergens is an important contributor to symptoms.
• Studies undertaken at high altitude suggest that
long-term avoidance of allergens and other exposures
can lead to reduced asthma symptoms.
• A new device has recently been shown to markedly reduce levels
of inhaled allergen and other particles using temperature
controlled laminar airflow (TLA).
• We undertook a multicentre randomized controlled trial
of nocturnal TLA treatment in atopic asthmatic patients.

Treatment response rate in patients treated
with temperature controlled laminar airflow (TLA)
or a placebo device for 1 year, defined as an
increase in Asthma Quality of Life Questionnaire
score of either ≥0.5 or ≥ 1.0 point.
 312 patients aged 7-70
with inadequately controlled
persistent atopic asthma.
 Proportion of patients
with an increase of ≥ 0.5 pts
in asthma quality of life score
after 1 yr of treatment.

*p<0.05, **p<0.01 relative to placebo.


Change in FeNO (ppb)
4 -

 312 patients aged 7-70 3 –

with inadequately controlled 2 – +2.82
persistent atopic asthma. 1 –
0
ACTIVE
 Proportion of patients -1 –
Placebo
with an increase of ≥ 0.5 pts -2 –
in asthma quality of life score -3 –
p=0.03
after 1 yr of treatment. -4 – -4.88
-5 –


Change in FeNO (ppb)
Inhalant exposure 4 -

 312 patients aged 7-70
reduction with TLA 3 –

with inadequately controlled
improves quality of 2 – +2.82
persistent atopic asthma.
life, airway inflammation 1 –
ACTIVE
 Proportion of and
0
patients Placebo
systemic allergy -1 –
with an increase of ≥ 0.5 pts
in patients with -2 –
in asthma quality of life score p=0.03
persistent -3 –
after 1 yr of treatment.
atopic asthma. -4 – -4.88
-5 –

Feather bedding and childhood asthma associated
with house dust mite sensitisation: a randomised
controlled trial. Glasgow Arch Dis Child 2011;96:541

Introduction
Observational studies report inverse associations between the use of
feather upper bedding (pillow and/or quilt) and asthma symptoms but there
is no randomised controlled trial evidence assessing the role of feather
upper bedding as a secondary prevention measure.

Objective
To determine whether, among children not using feather upper bedding,
a new feather pillow and feather quilt reduces asthma severity among house
dust mite (HDM) sensitised children with asthma over a 1-year period
compared with standard dust mite avoidance advice, and giving children a new
mite-occlusive mattress cover.


% children with frequent wheeze
70 – (≥4 episodes)
 197 children with HDM
sensitisation and moderate 60 – 63.8% ns
to severe asthma. 50 – 55.3%
 New upper bedding duck
40 –
feather pillow and quilt
and a mite-occlusive 30 –
mattress cover (feather)
20 –
 Standard care and a mite-
occlusive mattress cover 10 –
(standard).
0 Feather Standard
bedding care


 197 children with HDM
sensitisation and moderate
% children with
to severe asthma. speech-limiting wheeze
 New upper bedding duck
feather pillow and quilt 30 –
ns
and a mite-occlusive 22.6%
mattress cover (feather) 20 – 20.2%
 Standard care and a mite- 10 –
occlusive mattress cover
(standard). 0
Feather Standard
bedding care


% children with sleep disturbed because
of wheezing
 197 children with HDM 60 –
sensitisation and moderate ns
to severe asthma. 50 – 55.3%
 New upper bedding duck 50.0%
40 –

mattress cover (feather) 20 –

(standard). 0
Feather Standard
bedding care


% children with sleep disturbed because
of wheezing
 197 children with HDM 60 –
sensitisation and moderate ns
to severe asthmapillow
No cover . 50 – 55.3%
 New upper bedding duck 50.0%
or cover quilt
40 –

was provided.

mattress cover (feather) 20 –

(standard). 0
Feather Standard
bedding care

but
•A quarter (27 of 94) of feather group children reported using
synthetic pillows at trial end and one-third were not sleeping with
the feather pillow and quilt.

•Analysis by compliance rather than intention to treat raised the
possibility that feather bedding use was associated with reduced
respiratory symptoms and better lung function, a result in line with
the observational epidemiological findings.

•No regular laundry were used and thus in the high mite
environment of Sydney, surface allergen may have accumulated
similarly from non-bedding sources onto both types of bedding.


OR for frequent wheeze
(≥4 episodes)
 The association of
feather upper 2.0 –
bedding use (pillow
and quilt) and 1.5 – 1.88
respiratory
outcomes, with 1.0 –

further consideration 0.5 –
of child’s usual 0.61
sleeping position. 0 0
Non-supine Supine
children children
Feather bedding use


feather upper OR for speech-limiting wheeze
bedding use (pillow
and quilt) and 1.5 –
respiratory

0.90
of child’s usual 0.0
Non-supine Supine
children children
Feather bedding use


feather upper OR for sleep disturbed because of
wheezing (≥1 nights per week)
bedding use (pillow
and quilt) and 1.5 –
respiratory

of child’s usual 0.57 0.0
Non-supine Supine
children children
Feather bedding use


Intervention
 The association ofrisk
reduced the
feather upper being
of sleep OR for sleep disturbed because of
wheezing (≥1 nights per week)
bedding use (pillow
disturbed because
and quilt) and
of wheezing and 1.5 –
respiratory wheeze to
severe
outcomes, witha 1.0 –

further consideration
greater extent for 0.5 –
of child’s usual slept
children who 0.57 0.0
sleeping position.
supine. 0 0
Non-supine Supine
children children
Feather bedding use

House dust mite avoidance measures for perennial
allergic rhinitis: an updated Cochrane systematic review
Nurmatov, Allergy 2012;67:158

 HDM (house dust mite)
control measures 7 of the 9 trials reported
vs placebo. that, when compared with
control,
 Patients with the interventions studied
clinically proven
resulted in significant reduction
allergic rhinitis.
in HDM load.
 9 trials involving
501 participants.

House dust mite avoidance measures for perennial
allergic rhinitis: an updated Cochrane systematic review
Nurmatov, Allergy 2012;67:158

Interventions that
achieve substantial
reductions in HDM load may
 HDM (house dust mite) offer some benefit in reducing
control measures
rhinitis symptoms.
vs placebo.
 Patients with Isolated use of HDM
clinically proven impermeable bedding
allergic rhinitis. is unlikely to prove effective.
 9 trials involving Education is also neededd
501 participants.

Do young adults with childhood asthma avoid occupational
exposures at first hire? Dumas ERJ 2011;37:1043

% subjects exposed in
their first job
 298 children examined 50 –
(1991-1995).
 Job at follow-up in
2003-2007
40 –
47%
30 –
(aged 17-29 yrs).
 Exposure to dust, gases 20 –
and/or fumes in their
10 –
first occupation.
0


OR to be exposed
1.0 –

0.98
0.5 –
0.67 0.55
0
0.27
Pre-hire Severe University Not
onset asthma in degree university
asthmatics childhood degree


OR to besuggest a
Results exposed healthy worker hire
1.0 – effect in subjects with more severe or
more symptomatic asthma in chilhood.
Education may modulate self-selection. 0.98
0.5 –
0.67 0.55
0
0.27
Pre-hire Severe University Not
onset asthma in degree university
asthmatics childhood degree

EAACI Position Paper: Prevention of work-related
respiratory allergies among pre-apprentices or apprentices
and young workers Moscato G, Allergy 2011;66:1164

 Students starting career programs with exposure to high
molecular weight allergens have a substantial frequency of
specific sensitization to work-related allergens that is
related to atopy and bronchial hyperresponsiveness (BHR).

 The incidence of work-related symptoms is higher in the first
2–3 years after starting exposure and decrease afterward.

 Work-related rhinitis and asthma are more common in those
with pre-existing allergic rhinitis and/or BHR.


 At least for several allergens, sensitization to common inhalant
allergens is associated with the development of sensitization to
occupational allergens and the development of work-related
respiratory symptoms.
Atopy may interact with exposure-response relationships.

 A baseline health assessment should be performed before starting a
vocational school or work that includes exposure to respiratory
sensitizers, to identify personal determinants for the development of
sensitization and respiratory allergy, and/or to identify pre-existing
respiratory diseases susceptible to worsening with workplace exposure.


 Adolescents with asthma and allergy often do not consider these
conditions in their career choices and may not be aware of the
effects that work may have on asthma.

 There is a need for improved education of adolescents and
young adults with asthma as to the potential effects of work on
asthma.

 Environmental control is the cornerstone for prevention, and
every effort should be made to keep the workplaces as healthy
places.


 The physician in charge for the baseline health assessment should
discuss the results with the young adult helping her/him in making
the professional choice.

 The young adult should be educated to adopt all preventive measures
to limit occupational exposure to potential allergens and respiratory
irritants and to recognize and report immediately all possible
symptoms suggestive of onset of work-related respiratory allergies
or work-related exacerbations.

 Medical surveillance should be prioritized in the
first 2–3 years of exposure and scheduled according
to the clinical profile, exposure details, and
reliability of available tests.

Management of occupational asthma: cessation or
reduction of exposure? A systematic review of available
evidence Vandenplas ERJ 2011;38:804
OR for reduction of exposure compared with complete
avoidance for
10 –
10.23
09 –
 Reduction 08 –
or cessation 07 –
of exposure 06 –
in 9 and 5 05 – 5.6
studies, respe 04 –
ctively. 03 –
02 –
01 –
0.16 0.30
00
Improvement Recovery Symptoms BHR
of asthma symptoms worsening

Management of occupational asthma: cessation or
reduction of exposure? A systematic review of available
evidence Vandenplas ERJ 2011;38:804
OR for reduction of exposure compared with complete
avoidance for
10 –
These findings 10.23
09 –
indicate that the
 Reduction of 08
reduction
–
or cessation 07
exposure –
of exposure 06
cannot be –
in 9 and 5
routinely 05 – 5.6
studies, respean
advocated as 04 –
alternative to
ctively. 03 –
the cessation of
exposure. 02 –
01 –
0.16 0.30
00
Improvement Recovery Symptoms BHR
of asthma symptoms worsening

Pet shop workers: exposure, sensitization, and
work-related symptoms. Renström A, Allergy 2011;66:1081
% subjects presenting
60 -

53%
50 –

 Subjects (n = 59) from
40 –
24 pet shops.

 Questionnaire and lung
30 –
34%
function tests and skin
prick tests.
20 –
22%
10 –

0
nasal eye asthma
symptoms

% subjects presenting
60 -

53%
50 –
However,only
40 –
24 pet shops. (7%)
4 workers
were previously 30 –
34%
diagnosed with
asthma
prick tests
20 –
22%
10 –

0
nasal eye asthma
symptoms


% subjects sensitized to
work-related allergens
30 –

24 pet shops.
29%
20 –
prick tests 10 –

0


% subjects sensitized to
work-related allergens

The findings stress 30 –
the importance of
24 pet shops. the
improving 29%
knowledge of 20 –
health risks and
allergen avoidance
measures among
prick tests 10 –
pet shop staff

0

What 2012 allergen avoidance

Recomendados

Recomendados

Más contenido relacionado

La actualidad más candente

La actualidad más candente (20)

Similar a What 2012 allergen avoidance

Similar a What 2012 allergen avoidance (20)

Más de Envicon Medical Srl

Más de Envicon Medical Srl (20)

Último

Último (20)

What 2012 allergen avoidance