From MASK-air and SILAM to CATALYSE (Climate Action To Advance HeaLthY Societies in Europe)

Plant species vary under different climatic conditions and the distribution of pollen in the air. Trends in pollen distribution can be used to assess the impact of climate change on public health. In 2015, the Mobile Airways Sentinel networK for rhinitis and asthma (MASK-air®) was launched as a project of the European Innovation Partnership on Active and Healthy Ageing (EIP-on-AHA, DG Santé and DG CONNECT). This project aimed to develop a warning system to inform patients about the onset of the pollen season, namely, the System for Integrated modeLling of Atmospheric coMposition (SILAM). A global-to-meso-scale dispersion model was developed by the Finnish Meteorological Institute (FMI). It provides quantitative information on atmospheric pollution of anthropogenic and natural origins, particularly on allergenic pollens. Impact of Air Pollution on Asthma and Rhinitis (POLLAR, EIT Health) has combined MASK-air clinical data with SILAM forecasts. A new Horizon Europe grant (Climate Action to Advance HeaLthY Societies in Europe [CATALYSE]; grant agreement number 101057131), which came into force in September 2022, aims to improve our understanding of climate change and help us find ways to counteractit. One objective of this project is to develop early warning systems and predictive models to improve the effectiveness of strategies for adapting to climate change. One of the warning systems is focused on allergic rhinitis (CATALYSE Task 3.2), with a collaboration between the FMI (Finland), Porto University (Portugal), MASK-air SAS (France), ISGlobal (Spain), Hertie School (Germany), and the University of Zurich (Switzerland). It is to be implemented with the support of the European Academy of Allergy and Clinical Immunology. This paper reports the planning of CATALYSE Task 3.2.

Estimating personal solar ultraviolet radiation exposure through time spent outdoors, ambient levels and modelling approaches

BACKGROUND

 Evidence on validation of surrogates applied to evaluate the personal exposure levels of solar ultraviolet radiation (UVR) in epidemiological studies is scarce.

OBJECTIVES

 To determine and compare the validity of three approaches, including (i) ambient UVR levels, (ii) time spent outdoors, and (iii) a modelling approach integrating the aforementioned parameters, to estimate personal UVR exposure over a period of six months among indoor and outdoor workers and in different seasons (summer/winter).

METHODS

 This validation study was part of the EU ICEPURE project and was performed between July 2010 and January 2011 in a convenience sample of indoor and outdoor workers in Catalunya - Spain. We developed linear regression models to quantify the variation in the objectively measured personal UVR exposure that could be explained, separately, by the ambient UVR, time spent outdoors, and modelled UVR levels.

RESULTS

Our 39 participants - mostly male and with a median age of 35 years- presented a median daily objectively measured UVR of 0.37 standard erythemal doses (SEDs). The UVR dose was statistically significantly higher in summer and for outdoor workers. The modelled personal UVR exposure and self-reported time spent outdoors could reasonably predict the variation in the objectively measured personal UVR levels (R² = (0.75, 0.79)), whereas ambient UVR was a poor predictor (R² =0.21). No notable differences were found between seasons or occupation.

CONCLUSIONS

 Time outdoors and our modelling approach were reliable predictors and of value to be applied in epidemiological studies of the health effects of current exposure to UVR.

Treatment of allergic rhinitis during and outside the pollen season using mobile technology. A MASK study

Background

The analysis of mobile health (mHealth) data has generated innovative insights into improving allergic rhinitis control, but additive information is needed. A cross-sectional real-world observational study was undertaken in 17 European countries during and outside the estimated pollen season. The aim was to collect novel information including the phenotypic characteristics of the users.

Methods

The Allergy Diary–MASK-air–mobile phone app, freely available via Google Play and App, was used to collect the data of daily visual analogue scales (VASs) for overall allergic symptoms and medication use. Fluticasone Furoate (FF), Mometasone Furoate (MF), Azelastine Fluticasone Proprionate combination (MPAzeFlu) and eight oral H1-antihistamines were studied. Phenotypic characteristics were recorded at entry. The ARIA severity score was derived from entry data. This was an a priori planned analysis.

Results

9037 users filled in 70,286 days of VAS in 2016, 2017 and 2018. The ARIA severity score was lower outside than during the pollen season. Severity was similar for all treatment groups during the pollen season, and lower in the MPAzeFlu group outside the pollen season. Days with MPAzeFlu had lower VAS levels and a higher frequency of monotherapy than the other treatments during the season. Outside the season, days with MPAzeFlu also had a higher frequency of monotherapy. The number of reported days was significantly higher with MPAzeFlu during and outside the season than with MF, FF or oral H1-antihistamines.

Conclusions

This study shows that the overall efficacy of treatments is similar during and outside the pollen season and indicates that medications are similarly effective during the year.

Phenotyping asthma, rhinitis and eczema in MeDALL population-based birth cohorts: an allergic comorbidity cluster

BACKGROUND

Asthma, rhinitis and eczema often co-occur in children, but their interrelationships at the population level have been poorly addressed. We assessed co-occurrence of childhood asthma, rhinitis and eczema using unsupervised statistical techniques.

METHODS

We included 17 209 children at 4 years and 14 585 at 8 years from seven European population-based birth cohorts (MeDALL project). At each age period, children were grouped, using partitioning cluster analysis, according to the distribution of 23 variables covering symptoms 'ever' and 'in the last 12 months', doctor diagnosis, age of onset and treatments of asthma, rhinitis and eczema; immunoglobulin E sensitization; weight; and height. We tested the sensitivity of our estimates to subject and variable selections, and to different statistical approaches, including latent class analysis and self-organizing maps.

RESULTS

Two groups were identified as the optimal way to cluster the data at both age periods and in all sensitivity analyses. The first (reference) group at 4 and 8 years (including 70% and 79% of children, respectively) was characterized by a low prevalence of symptoms and sensitization, whereas the second (symptomatic) group exhibited more frequent symptoms and sensitization. Ninety-nine percentage of children with comorbidities (co-occurrence of asthma, rhinitis and/or eczema) were included in the symptomatic group at both ages. The children's characteristics in both groups were consistent in all sensitivity analyses.

CONCLUSION

At 4 and 8 years, at the population level, asthma, rhinitis and eczema can be classified together as an allergic comorbidity cluster. Future research including time-repeated assessments and biological data will help understanding the interrelationships between these diseases.

Severe chronic allergic (and related) diseases: a uniform approach--a MeDALL--GA2LEN--ARIA position paper

Concepts of disease severity, activity, control and responsiveness to treatment are linked but different. Severity refers to the loss of function of the organs induced by the disease process or to the occurrence of severe acute exacerbations. Severity may vary over time and needs regular follow-up. Control is the degree to which therapy goals are currently met. These concepts have evolved over time for asthma in guidelines, task forces or consensus meetings. The aim of this paper is to generalize the approach of the uniform definition of severe asthma presented to WHO for chronic allergic and associated diseases (rhinitis, chronic rhinosinusitis, chronic urticaria and atopic dermatitis) in order to have a uniform definition of severity, control and risk, usable in most situations. It is based on the appropriate diagnosis, availability and accessibility of treatments, treatment responsiveness and associated factors such as comorbidities and risk factors. This uniform definition will allow a better definition of the phenotypes of severe allergic (and related) diseases for clinical practice, research (including epidemiology), public health purposes, education and the discovery of novel therapies.

Early life environment, neurodevelopment and the interrelation with atopy

Both neurological and immunological systems are vulnerable to early life exposures. Neurological disorders and atopy have been related in animals and humans. Our main objective was to assess whether multiple exposures to early life determinants remain associated with neurodevelopment after considering the potential intermediate role of atopy. A second objective was to assess whether genes associated with atopy may inform about the potential neurotoxical mechanisms. Children were members of the AMICS birth cohort in Menorca (n=418, 87% of the recruited). General cognition was measured with the McCarthy Scales at age 4 and atopy through specific IgE at age 4 and prick test at age 6; 85 single nucleotide polymorphisms (SNPs) in 16 atopy and detoxification genes were genotyped. Among the 27 risk factors assessed, lower maternal social class, maternal smoking during pregnancy, being first born, shorter breastfeeding, higher DDT levels in cord blood, and higher indoor levels of NO2 (among the non-detoxifiers by GSTP1 polymorphism) were independently associated with poorer cognition. These associations were apparently not mediated by the relation between atopy and general cognition. Among the candidate atopic genes, variants in NQ01 (a detoxification gene) and NPRS1 (related with affective disorders like anxiety and stress management) had a significant association with general cognition (p-value<0.001). However, adjustment for the corresponding SNPs did not change the association between the early life determinants and general cognition. Multiple environmental pre-natal exposures were associated with neurodevelopment independently of their role in the immunological system. Atopic genes related to neurodevelopment suggest some potential mechanisms.

Risk factors of new-onset asthma in adults: a population-based international cohort study

BACKGROUND

The occurrence of new-onset asthma during adulthood is common, but there is insufficient understanding of its determinants including the role of atopy.

OBJECTIVE

To assess the risk factors for the development of new-onset asthma in middle-aged adults and to compare them according to atopy.

METHODS

A longitudinal analysis of 9175 young adults who participated in two surveys of the European Community Respiratory Health Survey (ECRHS) conducted 9 years apart.

FINDINGS

We observed 179 cases of new-onset asthma among 4588 participants who were free of asthma and reported at the beginning of the follow-up that they had never had asthma (4.5 per 1000 person-years). In a logistic regression, the following risk factors were found to increase the risk of new-onset asthma: female gender (OR: 1.97; 95% confidence interval (CI): 1.38, 2.81), bronchial hyperresponsiveness (3.25; 2.19, 4.83), atopy (1.55; 1.08, 2.21), FEV(1) < 100 % predicted (1.87; 1.34, 2.62), nasal allergy (1.98;1.39,2.84) and maternal asthma (1.91; 1.13; 3.21). Obesity, respiratory infections in early life and high-risk occupations increased the risk of new-onset asthma although we had limited power to confirm their role. Among the atopics, total IgE and sensitization to cat were independently related to the risk of new-onset asthma. The proportion of new-onset asthma attributable to atopy varied from 12% to 21%.

CONCLUSION

Adults reporting that they had never had asthma were at a substantial risk of new-onset asthma as a result of multiple independent risk factors including lung function. Atopy explains a small proportion of new-onset adult asthma.

Power and sample size calculations for longitudinal studies comparing rates of change with a time-varying exposure

Existing study design formulas for longitudinal studies have assumed that the exposure is time-invariant. We derived sample size formulas for studies comparing rates of change by exposure when the exposure varies with time within a subject, focusing on observational studies where this variation is not controlled by the investigator. Two scenarios are considered, one assuming that the effect of exposure on the response is acute and the other assuming that it is cumulative. We show that accurate calculations can often be obtained by providing the intraclass correlation of exposure and the exposure prevalence at each time point. When comparing rates of change, studies with a time-varying exposure are, in general, less efficient than studies with a time-invariant one. We provide a public access program to perform the calculations described in the paper (http://www.hsph.harvard.edu/faculty/spiegelman/optitxs.html).

Short-term respiratory effects of cleaning exposures in female domestic cleaners

Symptoms of obstructive lung disease in domestic cleaners have been related to the use of bleach and other irritant cleaning products. The short-term effects of cleaning exposures on respiratory symptoms and peak expiratory flow (PEF) were investigated in domestic cleaners with respiratory disorders. In a panel study, 43 female domestic cleaners with a recent history of asthma and/or chronic bronchitis completed a 2-week diary, collecting information on respiratory symptoms, PEF and cleaning exposures. Mixed regression models were used to assess daily changes in symptoms and PEF associated with specific cleaning exposures. The probability of having work-related asthma was individually assessed by a computerised diagnostic system and an occupational asthma expert. Lower respiratory tract symptoms were more common on working days and were predominantly associated with exposure to diluted bleach, degreasing sprays/atomisers and air fresheners. Associations with upper respiratory tract symptoms and PEF were less apparent. Eleven (30%) subjects scored positively for work-related asthma. It is concluded that exposure to certain irritant cleaning products aggravates lower respiratory tract symptoms in female domestic cleaners with asthma or chronic bronchitis.

Concentrations and determinants of NO2 in homes of Ashford, UK and Barcelona and Menorca, Spain

This study examined indoor nitrogen dioxide (NO2) concentrations in Ashford, Kent (UK), Menorca Island and Barcelona city (Spain) and the contribution of their most important indoor determinants (e.g. gas combustion appliances and cigarette smoking). The homes examined (n = 1421) were those from infants recruited for the Asthma Multicentre Infants Cohort Study, which aimed to assess, using a standard protocol, the effects of pre- and post-natal environmental exposures in the inception of atopy and asthma. Indoor NO2 was measured using passive filter badges placed on a living room wall of the homes for between 7 and 15 days. Homes in the three centers had significantly different concentrations of indoor NO2, with those in Barcelona showing the highest levels (median NO2 levels: 5.79, 6.06 and 23.87 p.p.b. in Ashford, Menorca and Barcelona, respectively). Multiple regression analysis showed that the principal indoor determinants of NO2 concentrations in the three cohorts were the heating/cooking fuel used in the house (gas fire increased average NO2 concentrations by 1.27-fold and gas cooker by 2.13 times), parental cigarette smoking and season of measurement. Those variables significantly related to indoor NO(2) accounted for 23, 14 and 39% of the variation in indoor NO2 concentration in Ashford, Barcelona and Menorca, respectively. In all the cohorts combined, 52% of the variation could be explained in this way. Although outdoor NO2 was not measured concurrently, its additional contribution was estimated. In conclusion, despite differences in indoor NO2 mean concentrations probably reflecting different outdoor NO2 level, home factors affecting indoor NO2 values and their specific contributions were constant across the three cohorts.

PRACTICAL IMPLICATIONS

This study found that principal determinants associated to indoor NO2 in three different sites of Europe: Ashford (UK), Barcelona and Menorca (Spain) were the energy source present in the home and cigarette smoking, despite these areas presented different climates, levels of outdoor contamination, housing characteristics and ventilation behavior. It is suggested that interventions in homes of these three centers will need to address principally cigarette smoking and gas combustion appliances. These latter factors require institutional intervention, while cigarette smoking mainly require personal changes.

Specific sensitization to common allergens and pulmonary function in the European Community Respiratory Health Survey

BACKGROUND

The role of atopy in the evolution to chronic obstructive disease remains controversial.

AIM

We aimed to assess the association between individual sensitization to common allergens and lung function.

METHOD

We analysed data from 12,687 subjects aged 20 to 44 years, from 34 centres in 15 countries participating in the European Community Respiratory Health Survey (ECRHS). Participants performed a blood test, lung function test, methacholine challenge, and answered an administered questionnaire. The relationships between specific IgE, FEV1 and FEV1/FVC ratio were assessed for each study centre stratified by sex, followed by random effects meta-analysis.

RESULTS

Asthmatics sensitized to house dust mite had a lower FEV1 (-119 mL in women and -112 mL in men) and FEV1/FVC ratio (-1.95%, and -2.48%) than asthmatics without sensitization. Asthmatics sensitized to cat had a lower FEV1 (statistically significant for women only) and a lower FEV1/FVC ratio. Asthmatic women sensitized to grass had a lower FEV1 and a lower ratio, and those sensitized to Cladosporium had a lower FEV1. A weak association was found with sensitization to cat and to Cladosporium among non-asthmatic women, which disappeared after adjusting for BHR.

CONCLUSION

We conclude that atopy was related to a lower lung function, which was only apparent among asthmatics. This relationship was explained by specific sensitization to cat and to house dust mite, the latter being homogeneous across areas.

Effect of nitrogen dioxide and ozone on the risk of dying in patients with severe asthma

BACKGROUND

A study was performed to assess the acute association between air pollution, pollen and spores, and mortality in a population based cohort of subjects with asthma recruited from emergency room admissions for an asthma exacerbation using a case crossover design.

METHODS

Patients in Barcelona aged over 14 years who died during the period 1985-95 who had visited the emergency department of one of the four largest hospitals in the city for asthma during 1985-9 were included in the study (a total of 467 men and 611 women). Deaths were identified by record linkage of the cohort individuals with the Catalonia mortality registry. Causes of death were based on the underlying cause on the death certificate. Air pollution, pollen and spore levels were measured at the city monitoring stations which provide an average for the entire city.

RESULTS

Nitrogen dioxide was associated with mortality for all causes of death (adjusted odds ratio (OR) for an increase of the interquartile range = 1.50, 95% confidence interval (CI) 1.09 to 2.64) in asthmatic patients with more than one emergency room admission for asthma. The association was particularly strong for respiratory causes (OR 1.63, 95% CI 0.93 to 2.86). Ozone also increased the risk of death in asthmatic patients (OR 1.90, 95% CI 1.09 to 3.30) during spring and summer. The association with particles, pollen, and spores was not significant, and no interactions between air pollutants and pollen and spores were found.

CONCLUSION

Nitrogen dioxide and ozone may exacerbate severe asthma and even cause death among asthmatic subjects.

Incidence of asthma and its determinants among adults in Spain

The objective was to measure the incidence of asthma and its determinants in Spain, where the prevalence of asthma is low to medium. A follow-up of subjects participating in the European Community Respiratory Health Survey (ECRHS) was conducted in 1998- 1999 (n = 1,640, 85% of those eligible). Subjects were randomly selected from the general population and were 20 to 44 yr old in 1991-1993. Time of follow-up was on average 6.75 yr (range, 5.3 to 7.9 yr). Asthma was defined as reporting ever having had asthma. The incidence of asthma was 5.53 (95% confidence interval, 4.28- 7.16) per 1,000 person-years (6.88 in females, 4.04 in males). Incidence was highest in subjects who at the baseline survey had bronchial hyperresponsiveness (incidence rate ratio [IRR], 3.85), in those with positive IgE against timothy grass (IRR, 3.16), and in females (IRR, 1.80). These results persisted after adjusting for respiratory symptoms at baseline. There was no significant association (p < 0.2) with high total serum IgE, atopy defined by reactivity to any allergen, smoking, occupational exposure, or maternal asthma. A sensitivity analysis using four definitions of population at risk yielded incidence rates varying from 5.53 to 1.50. In this population of subjects without self-reported asthma or asthma-type symptoms at baseline, bronchial hyperresponsiveness and IgE reactivity to grass appeared as the main determinants of new asthma.

Particles, and not gases, are associated with the risk of death in patients with chronic obstructive pulmonary disease

OBJECTIVES

We aim to assess the independent association of particles, after controlling for gaseous pollutants, with the risk of death among a cohort of patients with chronic obstructive pulmonary disease (COPD).

METHODS

Residents of Barcelona, aged over 35 years, who attended emergency room services for COPD exacerbation from 1985 to 1989 and who died in the period 1990-1995 (n = 2305) were selected. The analysis followed a case-crossover procedure with ambidirectional controls. Air pollution exposure (particulate matter <10 microm (PM(10)), ozone, nitrogen dioxide and carbon monoxide) was measured at the city monitoring stations.

RESULTS

Levels of PM(10) (odds ratio for the interquartile difference = 1.11, 95% CI : 1.00- 1.24), but not gaseous pollutants, were associated with mortality for all causes of death after adjusting for meteorological variables and influenza epidemics. In the two-pollutant models, the association of mortality with PM(10) was not confounded by the inclusion of gases, while the association of gaseous pollutants was notably reduced after adjustment for particles. There was no interaction between particles and gaseous pollutants.

CONCLUSIONS

Findings reinforce the deleterious role of urban particles as a trigger of death in COPD patients, and suggest that they are the major culprit among the air pollutants. The role of other pollutants, if any, was additive and not multiplicative.

International assessment of the internal consistency of respiratory symptoms. European Community Respiratory Health Study (ECRHS)

We aimed to assess cross-cultural validity of the reporting of respiratory symptoms in the European Community Respiratory Health Study (ECRHS). A random sample of subjects from the general population (aged 20-44 yr), from 35 centers in 15 countries, answered a questionnaire and underwent allergy tests and airway challenge with methacholine. The overall response rate to the questionnaire was 60% (n = 16,635). Exploratory factor analysis was used to identify how symptoms were grouped (i.e., to specify factor structure), using data from the United Kingdom. Subsequently, a confirmatory factor analysis of the prespecified structure for the United Kingdom was assessed for each country in consecutive nested models, increasing at each step the number of parameters forced to be equal to the United Kingdom, and assessing the goodness of fit. Variables were clustered in the same four groups (factors) in all countries. The four factors, mutually adjusted, were associated with either bronchial responsiveness, atopy, or smoking, which provides coherence for the separation of the four factors. In the confirmatory factor analysis, when the load of each of the symptoms in the corresponding factor was prespecified, all countries except Spain showed an adequate fit; in Spain there were differences in answers concerning asthma treatment. We conclude that the ECRHS multilingual translated respiratory symptoms questionnaire shows high internal consistency, suggesting that international comparisons are not affected by errors due to cross-cultural variations in the reporting of symptoms.