The role of outdoor air pollution and climatic changes on the rising trends in respiratory allergy

Evaluation of evidence for interaction between PM2.5 and aeroallergens on childhood asthma exacerbation in Philadelphia, PA, 2011 to 2016

Fine particulate matter (PM2.5) and aeroallergens (i.e., pollen, molds) are known triggers of asthma exacerbation. Despite mechanistic evidence suggesting synergistic effects between PM2.5 and asthma exacerbation, little epidemiologic work has been performed in children, which has exhibited inconsistency. We conducted a time-series study to explore their interactions using electronic health records (EHR) data in Philadelphia, PA, for asthma diagnoses in outpatient, emergency department [ED], and inpatient settings. Daily asthma exacerbation cases (28,540 asthma exacerbation case encounters) were linked to daily ambient PM2.5 and daily aeroallergen levels during the aeroallergen season of a six-year period (mid-March to October 2011-2016). Asthma exacerbation counts were modeled using quasi-Poisson regression, where PM2.5 and aeroallergens were fitted with distributed lag non-linear functions (lagged from 0 to 14-days), respectively, when modeled as the primary exposure variables. Regression models were adjusted for mean daily temperature/relative humidity, long-term and seasonal trends, day-of-week, and major U.S. holidays. Increasing gradient of RR estimates were observed for only a few primary exposure risk factors [PM2.5 (90th vs. 5th percentile)/aeroallergens (90th percentile vs. 0)], across different levels of effect modifiers. For example, RRs for the association between late-season grass pollen (lag1) and asthma exacerbation were higher at higher levels of PM2.5, 5-days preceding the exacerbation event (low PM2.5: RR = 1.01, 95% CI: 0.93-1.09; medium PM2.5: 1.04, 95% CI: 0.96-1.12; high PM2.5: 1.09, 95% CI: 1.01-1.19). However, most of the highest RRs for aeroallergens were instead observed for days with low- or medium- PM2.5 levels; likewise, when PM2.5 was modeled as the primary exposure with aeroallergens as the effect modifier. Most of the RR estimates did not exhibit gradients that suggested synergism, and were of relatively high imprecision. Overall, our study suggested no evidence for interactions between PM2.5 and aeroallergens in their relationships with childhood asthma exacerbation.

Pollen allergy: Developing multi-sectorial strategies for its prevention and control in lower and middle-income countries

Pollen allergy is considered a major public health problem that causes morbidity and subsequently affects a patient's quality of life. Pollen due to their large size cannot enter the thoracic regions of the respiratory tract but can affect the nasopharyngeal mucous membrane. At the same time, the submicronic-pollen particles can act as respirable particles reaching deeper into the upper airways leading to exacerbation of asthma, chronic obstructive pulmonary disease (COPD) and other allergic reactions. Based on the existing literature, expanding evidence shows that climate change and air pollutants could affect the pollen number, morphology, season, allergen content, and distribution pattern. Hence, this will influence the prevalence and occurrence of allergies linked to pollen exposure. Being a part of biogenic pollutants, pollen allergens are not expected to diminish in the foreseeable future. Therefore, it is imperative that steps need to be strengthened to improve and optimize preventive/adaptive strategies. This paper aims to review the major causes of widespread allergy, identify the major gaps, and suggest key preventive/adaptive measures to address the onset and exacerbation of pollen-related allergic diseases with a major focus on lower and middle-income countries. The study also discusses how-to implement the prevention and control measures at the individual, health care communities and organizations, Local Governments, National/International Governments levels to decrease the risk of illnesses associated with pollen allergy.

The influence of air pollution on pollen allergy sufferers

A multitude of consequences from global warming and environmental pollution can already be seen for nature and humans. The continuous burning of fossil fuels leads to rising temperatures and rising water levels causing extreme weather phenomena like heat waves and flooding. Increasing levels of air pollution also cause adverse health effects. This is especially important for pollen allergy sufferers because air pollution plays a central role in the interactions between pollen and humans. Today, pollen allergy sufferers are confronted with longer pollen seasons and pollen with potentially increased allergenicity. The effects for pollen allergy sufferers are an increased duration and severity of symptoms. New research results from the Medical University of Vienna prove that out of the most important air pollution parameters (particulate matter, nitrogen dioxide, sulfur dioxide, and ozone) especially ozone causes increased symptom severity in pollen allergy sufferers during the birch, grass, and ragweed pollen seasons.

A systematic review of the effects of temperature and precipitation on pollen concentrations and season timing, and implications for human health

Climate and weather directly impact plant phenology, affecting airborne pollen. The objective of this systematic review is to examine the impacts of meteorological variables on airborne pollen concentrations and pollen season timing. Using PRISMA methodology, we reviewed literature that assessed whether there was a relationship between local temperature and precipitation and measured airborne pollen. The search strategy included terms related to pollen, trends or measurements, and season timing. For inclusion, studies must have conducted a correlation analysis of at least 5 years of airborne pollen data to local meteorological data and report quantitative results. Data from peer-reviewed articles were extracted on the correlations between seven pollen indicators (main pollen season start date, end date, peak date, and length, annual pollen integral, average daily pollen concentration, and peak pollen concentration), and two meteorological variables (temperature and precipitation). Ninety-three articles were included in the analysis out of 9,679 articles screened. Overall, warmer temperatures correlated with earlier and longer pollen seasons and higher pollen concentrations. Precipitation had varying effects on pollen concentration and pollen season timing indicators. Increased precipitation may have a short-term effect causing low pollen concentrations potentially due to "wash out" effect. Long-term effects of precipitation varied for trees and weeds and had a positive correlation with grass pollen levels. With increases in temperature due to climate change, pollen seasons for some taxa in some regions may start earlier, last longer, and be more intense, which may be associated with adverse health impacts, as pollen exposure has well-known health effects in sensitized individuals.

Towards a model of wet deposition of bioaerosols: The raindrop size role

Bioaerosols play a major role in the plant life of ecosystems. In addition, they have a profound impact on human health, since they may cause lung diseases or allergies. The key objective of this study is to assess the below cloud scavenging effect of rainfall on pollen concentration. The analysis is based on a sampling carried out in León, Spain, between 2015 and 2018. The rainfall variables and the pollen concentrations have been obtained with a disdrometer and a volumetric Hirst type spore-trap, respectively. In order to evaluate the scavenging, three parameters have been calculated: scavenging efficiency (through the concentration-weighted average (%ΔC)), the scavenging coefficient (λ) and the percentage of events with a decrease in pollen concentration (%ES) also called events with effective scavenging. 71% of rain events presented an effective scavenging that affected all types of pollen. The %ΔC mean value of total pollen was 24 ± 18% (positive values indicate an effective scavenging) and the types of pollen with the highest values were Castanea and Cupressaceae (71 and 40%, respectively). A linear model (R² = 0.94) to estimate the pollen concentration after rain was built with variables such as pollen concentration before rain and other variables from a weather station and a disdrometer. Furthermore, we have shown the possibility of knowing in real time the probable Cupressaceae pollen concentration, from the initial pollen concentration and the physical parameters of rain (such as raindrop size, rain intensity or volume swept by raindrops in their falling path).

Impact of elevated air temperature and drought on pollen characteristics of major agricultural grass species

Grass pollen allergens are known to be one of the major triggers of hay fever with an increasing number of humans affected by pollen associated health impacts. Climate change characterized by increasing air temperature and more frequent drought periods might affect plant development and pollen characteristics. In this study a one-year (2017) field experiment was conducted in Bavaria, Germany, simulating drought by excluding rain and elevated air temperature by installing a heating system to investigate their effects primarily on the allergenic potential of eight selected cultivars of the two grass species timothy and perennial ryegrass. It could be shown for timothy that especially under drought and heat conditions the allergen content is significantly lower accompanied by a decrease in pollen weight and protein content. In perennial ryegrass the response to drought and heat conditions in terms of allergen content, pollen weight, and protein content was more dependent on the respective cultivar probably due to varying requirements for their growth conditions and tolerance to drought and heat. Results support recommendations which cultivars should be grown preferentially. The optimal choice of grass species and respective cultivars under changing climate conditions should be a major key aspect for the public health sector in the future.

Numerical modelling of birch pollen dispersion in Canada

Simulating allergenic tree pollen is important to protect sensitive population and to support bioaerosols monitoring effort. Using the regional air quality model GEM-MACH, a simulation was conducted adopting two new main hypotheses: 1) the use of vertical correlation concept to force the vertical dispersion (a method normally used in tracer data assimilation) and, 2) the use of a puff instead of a continuous pollen release. The simulation was compared with pollen observations in Montreal and with the corresponding statistical forecasts (issued daily by the Weather Network) at several locations in the province of Quebec and elsewhere. The comparison with the simulation was found satisfactory (outperform forecasts based on persistence or pollen calendar and is also superior to numerical simulation of tree pollen done elsewhere in North America). Simulation shows that, for the 2012 pollen season, the majority (88%) of the Betula pollen measured in Montreal originated from the Laurentides region. Another result of scientific importance obtained here is that Betula pollen episodes (observed or simulated birch pollen) in Montreal occur only when the average daily temperature is in the range of 10° to 18 °C. This research is considered as a first step in forecasting bioaerosols in Canada within an air quality model.

Climate Change and Pollen Allergy in India and South Asia

Increased levels of CO₂ and various greenhouse gases cause global warming and, in combination with pollutants from fossil fuel combustion and vehicular and industrial emissions, have been driving increases in noncommunicable diseases across the globe, resulting a higher mortality and morbidity. Respiratory diseases and associated allergenic manifestations have increased worldwide, with rates higher in developing countries. Pollen allergy serves as a model for studying the relationship between air pollution and respiratory disorders. Climate changes affect the quality and amount of airborne allergenic pollens, and pollutants alter their allergenicity, resulting in greater health impacts, especially in sensitized individuals.

Assessment of pulmonary functions among traffic police personnel in Chennai city - A comparative cross-sectional study

Background:

Air pollution due to road traffic is a solemn health hazard and vehicular emissions due to huge population in the cities are the main reason for the air quality crisis. The study was conducted to assess the degree of impairment in lung function in traffic police personnel exposed to traffic pollution compared to less-exposed healthy subjects.

Materials and Methods:

This comparative cross-sectional study was conducted among 250 traffic police personnel, aged 20–55 years, working in Chennai city, as compared to a matched control group, consisting of 250 less-exposed subjects. Measurement of pulmonary function testing was done with an RMS Helio 401. Statistical analysis was carried out with R statistical software.

Results:

The traffic police personnel had significantly (P < 0.05) declined FEV1 and FEV1/FVC ratio and FEF 25–75% (L/s) as compared to controls. Traffic personnel with longer duration of exposure showed significantly (P < 0.05) reduced lung functions than those with shorter duration. We have found a significant negative correlation with all pulmonary function parameters such as FVC, FEV1, FEV1/FVC, PEFR, and FVC 25%–75% among the traffic police personnel.

Conclusion:

The impairment of pulmonary function among the traffic police personnel might be due to the effect of pollution by vehicular exhausts and they should be offered personal protective or preventive measures.

Impact of air pollution on symptom severity during the birch, grass and ragweed pollen period in Vienna, Austria: Importance of O3 in 2010-2018

Air pollution is a threat to the general population, especially to pollen allergy sufferers in urban environments. Different air quality parameters have hitherto been examined which add to the burden of pollen allergy sufferers. Parameters such as NO₂, SO₂, PM₁₀, PM_2.5, and O₃ are supposed to have additional impact, not only on health in general (increase in asthma, allergy sensitization frequency), but also on pollen grains (increase of allergenicity). However, it remains unknown if those air quality parameters increase symptom severity during the pollen season. We selected the birch, grass, and ragweed pollen seasons as different time periods throughout the year and analyzed the relationship of symptom data to pollen, air quality, and meteorological data (temperature, relative humidity) for the metropolis of Vienna (Austria). A linear regression model was computed based on different symptom data, and both pollen and air quality data were tested simultaneously. Ozone was positively and significantly associated with symptom scores in all three seasons, whereas this was only rarely the case with other pollutants. Therefore, only ozone was selected for further analysis in a model including meteorological parameters. In this model, effect estimates of ozone were attenuated but remained significant for the grass pollen season. The lack of significance in the other seasons may be attributed to the less numerous symptom data entries and the shorter duration of the pollen seasons for birch and ragweed. All other air quality parameters usually showed lower concentrations during the pollen seasons and displayed little variation. This might explain the lack of a clear signal. Our results suggest that today's allergic population is already affected by air quality (rising O₃ levels). Air quality should be considered as well in pollen information and pollen allergy studies in general because of its increasing importance in the light of global warming.

The effectiveness of thunder fire moxibustion for treating allergic rhinitis: A protocol for systematic review and meta analysis

BACKGROUND

Allergic rhinitis (AR) is a chronic disease, resulting in severe syndromes such as sneezing, itching, nasal blockage, and rhinorrhea. The major medications treating AR cause side effects, while thunder fire moxibustion (TFM) is known as a safe and effective treatment for AR. Thus, this systematic review and meta analysis aims to systematically evaluate the effectiveness and safety of TFM in the treatment of AR.

METHODS

Nine databases, including Medline, PubMed, Web of Science, Embase, the Cochrane Library, China National Knowledge Infrastructure Database (CNKI), WanFang Database (WF), Chinese Scientific Journal Database (VIP), and Chinese Biomedical Literature Database (CBM) from inception to July 2020 will be searched. In addition, the grey literature and the references of all included literature will be retrieved manually. Reviewers will identify studies, extract data and assess the quality independently. The outcomes of interest include: total nasal symptom score, total non-nasal symptom score, rhinitis quality of life questionnaire, visual analog scale, Laboratory indicators: serum immunoglobulin E, immunoglobulin A, or immunoglobulin G level and adverse events. Randomized clinical trials will be collected, methodological quality will be evaluated using the Cochrane risk-of-bias assessment tool, and the level of evidence will be rated using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach. Meta-analysis will be performed using RevMan5.3.0 software.

RESULTS

Because the review is ongoing, no results can be reported.

CONCLUSIONS

The findings from this review will provide reliable evidence for effectiveness and safety of TFM for AR.

ETHICS AND DISSEMINATION

Ethical approval requirements are not necessary for this review. This systematic review and meta analysis will be disseminated online and on paper to help guide the clinical practice better.

PROSPERO REGISTRATION NUMBER

CRD42019141113.

Effectiveness and safety of indirect moxibustion for the treatment of allergic rhinitis: A protocol for systematic review and meta-analysis of RCTs

BACKGROUND

Allergic rhinitis (AR) is a common allergic disorder worldwide. Western medicine is not optimistic about the therapeutic effect of this disease. However, moxibustion can enhance vital energy or immunity through a great number of clinical trials. Thus, the aim of this systematic review and meta-analysis is to systematically evaluate the effectiveness and safety of indirect moxibustion for treating AR.

METHODS

We will conduct a comprehensive literature search in Medline, PubMed, Web of Science, Embase, the Cochrane Library, China National Knowledge Infrastructure Database, WanFang Database, Chinese Scientific Journal Database, and Chinese Biomedical Literature Database from inception to August 2020 without any language restriction. In addition, we will retrieve the unpublished studies and the references of initially included literature manually. Reviewers will identify studies, extract data, and assess the quality independently. The outcomes of interest include: total effective rate, total nasal symptom score, total non-nasal symptom score, rhinitis quality of life questionnaire, visual analog scale, laboratory indicators (i.e., serum levels of IgE, IgA, or IgG), and adverse events. Randomized clinical trials will be collected, methodological quality will be evaluated using the Cochrane risk-of-bias assessment tool, and the level of evidence will be rated using the Grading of Recommendations, Assessment, Development and Evaluation approach. Meta-analysis will be performed using RevMan 5.3.0 software. The heterogeneity test will be conducted between the studies, and P < .1 and I > 50% are the thresholds for the tests. We will utilize the fixed effects model or the random effects model according to the size of heterogeneity.

RESULTS

Because the review is ongoing, no results can be reported.

CONCLUSIONS

The results of this review will provide reliable evidence for effectiveness and safety of indirect moxibustion for treating AR.

ETHICS AND DISSEMINATION

Ethical approval is not required for this study. This systematic review and meta-analysis will be disseminated online and on paper to help guide clinicians.

PROSPERO REGISTRATION NUMBER

CRD42019140944.

Conurbation, Urban, and Rural Living as Determinants of Allergies and Infectious Diseases: Royal College of General Practitioners Research and Surveillance Centre Annual Report 2016-2017

BACKGROUND

Living in a conurbation, urban, or rural environment is an important determinant of health. For example, conurbation and rural living is associated with increased respiratory and allergic conditions, whereas a farm or rural upbringing has been shown to be a protective factor against this.

OBJECTIVE

The objective of the study was to assess differences in general practice presentations of allergic and infectious disease in those exposed to conurbation or urban living compared with rural environments.

METHODS

The population was a nationally representative sample of 175 English general practices covering a population of over 1.6 million patients registered with sentinel network general practices. General practice presentation rates per 100,000 population were reported for allergic rhinitis, asthma, and infectious conditions grouped into upper and lower respiratory tract infections, urinary tract infection, and acute gastroenteritis by the UK Office for National Statistics urban-rural category. We used multivariate logistic regression adjusting for age, sex, ethnicity, deprivation, comorbidities, and smoking status, reporting odds ratios (ORs) with 95% CIs.

RESULTS

For allergic rhinitis, the OR was 1.13 (95% CI 1.04-1.23; P=.003) for urban and 1.29 (95% CI 1.19-1.41; P<.001) for conurbation compared with rural dwellers. Conurbation living was associated with a lower OR for both asthma (OR 0.70, 95% CI 0.67-0.73; P<.001) and lower respiratory tract infections (OR 0.94, 95% CI 0.90-0.98; P=.005). Compared with rural dwellers, the OR for upper respiratory tract infection was greater in urban (OR 1.06, 95% CI 1.03-1.08; P<.001) but no different in conurbation dwellers (OR 1.00, 95% CI 0.97-1.03; P=.93). Acute gastroenteritis followed the same pattern: the OR was 1.13 (95% CI 1.01-1.25; P=.03) for urban dwellers and 1.04 (95% CI 0.93-1.17; P=.46) for conurbation dwellers. The OR for urinary tract infection was lower for urban dwellers (OR 0.94, 95% CI 0.89-0.99; P=.02) but higher in conurbation dwellers (OR 1.06, 95% CI 1.00-1.13; P=.04).

CONCLUSIONS

Those living in conurbations or urban areas were more likely to consult a general practice for allergic rhinitis and upper respiratory tract infection. Both conurbation and rural living were associated with an increased risk of urinary tract infection. Living in rural areas was associated with an increased risk of asthma and lower respiratory tract infections. The data suggest that living environment may affect rates of consultations for certain conditions. Longitudinal analyses of these data would be useful in providing insights into important determinants.

Respiratory Symptoms in Relation to Living near a Crude Oil First Treatment Plant in Italy: A Cross-Sectional Study

Exposure to air pollution has been shown to increase the risk of developing chronic respiratory diseases. The largest crude oil first treatment plant in Italy emits harmful polluting substances. This cross-sectional study assesses the occurrence of respiratory symptoms in a sample of the adult population living near the plant. A proximal and a reference area were defined in order to recruit 200 subjects. Each subject performed a spirometry test and completed a questionnaire. Associations between the distance from the plant and selected respiratory outcomes were assessed (distance-based approach). The prevalence of outcomes between a proximal and a reference area (area-based approach) were also compared. Odds ratios were adjusted for potential confounders. Living near the plant was associated with a higher prevalence of respiratory symptoms, with significant associations for severe dyspnoea equivalent to the halving of risk as the distance of residence from the plant increased by 1 km (adjusted odds ratio (OR) 0.48, confidence interval at the 95% probability level (95% CI): 0.25⁻0.92). Several signals emerged for respiratory allergic symptoms. The area-based approach generally confirmed the results obtained with the distance-based approach. This is the first study to be carried out on a crude oil first treatment plant aimed at assessing the association with the occurrence of respiratory symptoms. These findings contribute to the evidence supporting the need for a space⁻time surveillance system in the investigated area.

Extracts of different pollen species and their effect on human tear fluid and an epithelial cell line

PURPOSE

Hazelnut and birch pollen are known to destroy tear film components and attack ocular surface cells. We investigated further pollen species from different plant families, whether they show similar effects on human tear fluid and an epithelial cell line in vitro, to provide a broad basis for further research on pollen reactions affecting the tear film and ocular surface.

MATERIALS AND METHODS

Regional pollen species from different plant families (Adoxaceae, Betulaceae, Fagaceae, Juglandaceae, Malvaceae, Oleaceae, Pinaceae, Plantaginaceae, Poaceae, Salicaceae, Sapindaceae) were collected. Their proteolytic activity was evaluated by Zymography. Human tear fluid and cells of an epithelial cell line were incubated with pollen extracts. Tear fluid was analyzed by Polyacrylamide gel electrophoresis (PAGE). Cytomorphology was assessed microscopically and cell viability by proliferation (MTS), water-soluble tetrazolium (WST-1) assay and the impedance-based xCELLigence real-time analysis (RTCA).

RESULTS

Zymography revealed significant protease activity and PAGE showed the degradation of tear proteins by different pollen species. Cells incubated with pollen extracts presented dose- and time-dependent cytomorphological changes. MTS, WST-1, and RTCA revealed cytostatic as well as cytotoxic effects of pollen extracts.

CONCLUSIONS

Pollen species from different plant families exert proteolytic activity and degrade human tear fluid as well as epithelial cells, which may play a crucial role in the pathogenesis of allergic and non-allergic reactions affecting the ocular surface.

Aeroallergens in Canada: Distribution, Public Health Impacts, and Opportunities for Prevention

Aeroallergens occur naturally in the environment and are widely dispersed across Canada, yet their public health implications are not well-understood. This review intends to provide a scientific and public health-oriented perspective on aeroallergens in Canada: their distribution, health impacts, and new developments including the effects of climate change and the potential role of aeroallergens in the development of allergies and asthma. The review also describes anthropogenic effects on plant distribution and diversity, and how aeroallergens interact with other environmental elements, such as air pollution and weather events. Increased understanding of the relationships between aeroallergens and health will enhance our ability to provide accurate information, improve preventive measures and provide timely treatments for affected populations.

Outdoor air pollution and respiratory health: a bibliometric analysis of publications in peer-reviewed journals (1900 - 2017)

BACKGROUND

Outdoor air pollution is a major threat to global public health that needs responsible participation of researchers at all levels. Assessing research output is an important step in highlighting national and international contribution and collaboration in a certain field. Therefore, the aim of this study was to analyze globally-published literature in outdoor air pollution - related respiratory health.

METHOD

Outdoor air pollution documents related to respiratory health were retrieved from Scopus database. The study period was up to 2017. Mapping of author keywords was carried out using VOSviewer 1.6.6.

RESULTS

Search query yielded 3635 documents with an h-index of 137. There was a dramatic increase in the number of publications in the last decade of the study period. The most frequently encountered author keywords were: air pollution (835 occurrences), asthma (502 occurrences), particulate matter (198 occurrences), and children (203 occurrences). The United States of America ranked first (1082; 29.8%) followed by the United Kingdom (279; 7.7%) and Italy (198; 5.4%). Annual research productivity stratified by income and population size indicated that China ranked first (22.2) followed by the USA (18.8). Analysis of regional distribution of publications indicated that the Mediterranean, African, and South-East Asia regions had the least contribution. Harvard University (92; 2.5%) was the most active institution/organization followed the US Environmental Protection Agency (89; 2.4%). International collaboration was restricted to three regions: Northern America, Europe, and Asia. The top ten preferred journals were in the field of environmental health and respiratory health. Environmental Health Perspective was the most preferred journal for publishing documents in outdoor pollution in relation to respiratory health.

CONCLUSION

Research on the impact of outdoor air pollution on respiratory health had accelerated lately and is receiving a lot of interest. Global research networks that include countries with high level of pollution and limited resources are highly needed to create public opinion in favor of minimizing outdoor air pollution and investing in green technologies.

International Consensus Statement on Allergy and Rhinology: Allergic Rhinitis

BACKGROUND

Critical examination of the quality and validity of available allergic rhinitis (AR) literature is necessary to improve understanding and to appropriately translate this knowledge to clinical care of the AR patient. To evaluate the existing AR literature, international multidisciplinary experts with an interest in AR have produced the International Consensus statement on Allergy and Rhinology: Allergic Rhinitis (ICAR:AR).

METHODS

Using previously described methodology, specific topics were developed relating to AR. Each topic was assigned a literature review, evidence-based review (EBR), or evidence-based review with recommendations (EBRR) format as dictated by available evidence and purpose within the ICAR:AR document. Following iterative reviews of each topic, the ICAR:AR document was synthesized and reviewed by all authors for consensus.

RESULTS

The ICAR:AR document addresses over 100 individual topics related to AR, including diagnosis, pathophysiology, epidemiology, disease burden, risk factors for the development of AR, allergy testing modalities, treatment, and other conditions/comorbidities associated with AR.

CONCLUSION

This critical review of the AR literature has identified several strengths; providers can be confident that treatment decisions are supported by rigorous studies. However, there are also substantial gaps in the AR literature. These knowledge gaps should be viewed as opportunities for improvement, as often the things that we teach and the medicine that we practice are not based on the best quality evidence. This document aims to highlight the strengths and weaknesses of the AR literature to identify areas for future AR research and improved understanding.

Association between ambient particulate matter and disorders of vestibular function

BACKGROUND

Exposure to environmental chemicals has been suggested to alter the physiologic state of the inner and middle ear. However, it is unknown if particulate matter exposure is associated with acute vestibular dysfunction.

OBJECTIVES

To estimate the effects of particulate matter exposure on the number of hospital visits related to three major diseases of vestibular dysfunction, Meniere's disease (MD), benign paroxysmal positional vertigo (BPPV), and vestibular neuronitis (VN).

METHODS

Our study subject is from Korean National Health Insurance Service-National Sample Cohort, which is dynamic cohort consist of 1 million participants representing the Korean population. Among total cohort participants, we used the hospital visit data of 210,000 individuals who resided in Seoul from 2007 to 2010. Time series analysis using the Poisson generalized additive model and case-crossover analysis using conditional logistic regression were used to investigate the association between daily particulate matter levels (PM_2.5, particulate matter <2.5μg/m³; PM₁₀, particulate matter <10μg/m³; PM_10-2.5, PM₁₀- PM_2.5) and number of MD, BPPV, and VN hospital visits.

RESULTS

Time series analysis showed that an interquartile range (IQR) increase in PM₁₀ and PM_10-2.5 on lag day 1 was associated with an increased risk of MD hospital visits [relative risk (RR), 95% confidence interval (CI), PM₁₀: 1.09 (1.02-1.15); PM_10-2.5: 1.06 (1.02-1.10)]. In addition, elderly individuals (≥60 years old) showed an increased risk of MD hospital visits after particulate matter exposure when compared to younger individuals. An IQR increase in particulate matter on lag day 1 was associated with a marginally significant increase in VN hospital visits [RR (95%CI), PM_2.5: 1.11 (0.98-1.25); PM₁₀: 1.07 (0.99-1.15); PM_10-2.5: 1.04 (0.99-1.09)]. However, no association between particulate matter exposure and BPPV hospital visits was noted. Case-crossover analyses showed similar results to the time-series analysis across all three diseases.

CONCLUSION

MD hospital visits were associated with ambient particulate matter exposure. Elderly individuals, in particular, were more susceptible to particulate matter exposure than younger individuals.

The effects of air pollution on asthma hospital admissions in Adelaide, South Australia, 2003-2013: time-series and case-crossover analyses

BACKGROUND

Air pollution can have adverse health effects on asthma sufferers, but the effects vary with geographic, environmental and population characteristics. There has been no long time-series study in Australia to quantify the effects of environmental factors including pollen on asthma hospitalizations.

OBJECTIVES

This study aimed to assess the seasonal impact of air pollutants and aeroallergens on the risk of asthma hospital admissions for adults and children in Adelaide, South Australia.

METHODS

Data on hospital admissions, meteorological conditions, air quality and pollen counts for the period 2003-2013 were sourced. Time-series analysis and case-crossover analysis were used to assess the short-term effects of air pollution on asthma hospitalizations. For the time-series analysis, generalized log-linear quasi-Poisson and negative binomial regressions were used to assess the relationships, controlling for seasonality and long-term trends using flexible spline functions. For the case-crossover analysis, conditional logistic regression was used to compute the effect estimates with time-stratified referent selection strategies.

RESULTS

A total of 36,024 asthma admissions were considered. Findings indicated that the largest effects on asthma admissions related to PM_2.5 , NO₂ , PM₁₀ and pollen were found in the cool season for children (0-17 years), with the 5-day cumulative effects of 30.2% (95% CI: 13.4-49.6%), 12.5% (95% CI: 6.6-18.7%), 8.3% (95% CI: 2.5-14.4%) and 4.2% (95% CI: 2.2-6.1%) increases in risk of asthma hospital admissions per 10 unit increments, respectively. The largest effect for ozone was found in the warm season for children with the 5-day cumulative effect of an 11.7% (95% CI: 5.8-17.9%) increase in risk of asthma hospital admissions per 10 ppb increment in ozone level.

CONCLUSION

Findings suggest that children are more vulnerable and the associations between exposure to air pollutants and asthma hospitalizations tended to be stronger in the cool season compared to the warm season, with the exception of ozone. This study has important public health implications and provides valuable evidence for the development of policies for asthma management.

Short-Term Effect of Pollen and Spore Exposure on Allergy Morbidity in the Brussels-Capital Region

Belgium is among the European countries that are the most affected by allergic rhinitis. Pollen grains and fungal spores represent important triggers of symptoms. However, few studies have investigated their real link with disease morbidity over several years. Based on aeroallergen counts and health insurance datasets, the relationship between daily changes in pollen, fungal spore concentrations and daily changes in reimbursable systemic antihistamine sales has been investigated between 2005 and 2011 in the Brussels-Capital Region. A Generalized Linear Model was used and adjusted for air pollution, meteorological conditions, flu, seasonal component and day of the week. We observed an augmentation in drug sales despite no significant increase in allergen levels in the long term. The relative risk of buying allergy medications associated with an interquartile augmentation in pollen distributions increased significantly for Poaceae, Betula, Carpinus, Fraxinus and Quercus. Poaceae affected the widest age group and led to the highest increase of risk which reached 1.13 (95% CI [1.11-1.14]) among the 19- to 39-year-old men. Betula showed the second most consistent relationship across age groups. Clear identification of the provoking agents may improve disease management by customizing prevention programmes. This work also opens several research perspectives related to impact of climate modification or subpopulation sensitivity.

Sensitization pattern of inhalant allergens in children with asthma who are living different altitudes in Turkey

Variability in children's allergic sensitization has been detected not only among different countries but also among cities within the same nation but yet different climatic areas. The aim of this study was to investigate the sensitization pattern of asthmatic children who lived in different altitude areas: the two largest Turkish cities, Istanbul (sea level) and Erzurum (high altitude). Five hundred and twelve asthmatic children (6-15 years old) from Istanbul (western Turkey, at sea level) and 609 from Erzurum (eastern Turkey, at an altitude of 1800 m) were included in the study. All participants underwent skin testing with common inhalant allergens, spirometry, total IgE level, and clinical examination. The positive sensitization ratio to aeroallergens in children with asthma living at sea level was statistically higher than that in children living in the high altitude group [p = 0.001, OR (odds ratio) 4.9 (confidence interval (CI) 3.67-6.459)]. However, pollen sensitization in asthmatic children living in high altitudes was significantly higher than that in children living at sea level [p = 0.00, OR 2.6 (CI 1.79-3.87)]. Children with asthma who live at high altitudes are characterized by higher pollen but lower mite sensitization rates than those living at sea level in Turkey. Different climatic conditions and altitudes may affect aeroallergen sensitization in children with asthma.

Occupational Exposure to Urban Air Pollution and Allergic Diseases

Exposure to air pollution is associated with increased morbidity from cardiovascular diseases, lung cancer, respiratory and allergic diseases. The aim of this study was to investigate allergic diseases in 111 traffic wardens compared to a control group of 101 administrative employees. All participating subjects underwent a physical examination, in which a complete medical history was taken and a dedicated allergological questionnaire administered. Spirometry, Specific IgE dosage (RAST) and skin prick tests (SPT) were done. Diagnostic investigations such as the nasal cytology, a specific nasal provocation test and rhinomanometry were also performed. Statistical analyses were performed using STATA version 11. The percentage of subjects with a diagnosis of allergy was higher in the exposed workers than in the controls. As regards the clinical tests, the positivity was higher for the group of exposed subjects. Among the exposed workers, those who worked on foot or motorcycle had a higher positivity in clinical trials compared to the traffic wardens who used the car. Our study showed a higher percentage of allergic subjects in the group of workers exposed to outdoor pollutants than in the controls. These results suggest that allergological tests should be included in the health surveillance protocols for workers exposed to outdoor pollutants.

Meteorological conditions, climate change, new emerging factors, and asthma and related allergic disorders. A statement of the World Allergy Organization

The prevalence of allergic airway diseases such as asthma and rhinitis has increased dramatically to epidemic proportions worldwide. Besides air pollution from industry derived emissions and motor vehicles, the rising trend can only be explained by gross changes in the environments where we live. The world economy has been transformed over the last 25 years with developing countries being at the core of these changes. Around the planet, in both developed and developing countries, environments are undergoing profound changes. Many of these changes are considered to have negative effects on respiratory health and to enhance the frequency and severity of respiratory diseases such as asthma in the general population.

Increased concentrations of greenhouse gases, and especially carbon dioxide (CO₂), in the atmosphere have already warmed the planet substantially, causing more severe and prolonged heat waves, variability in temperature, increased air pollution, forest fires, droughts, and floods – all of which can put the respiratory health of the public at risk. These changes in climate and air quality have a measurable impact not only on the morbidity but also the mortality of patients with asthma and other respiratory diseases. The massive increase in emissions of air pollutants due to economic and industrial growth in the last century has made air quality an environmental problem of the first order in a large number of regions of the world. A body of evidence suggests that major changes to our world are occurring and involve the atmosphere and its associated climate. These changes, including global warming induced by human activity, have an impact on the biosphere, biodiversity, and the human environment. Mitigating this huge health impact and reversing the effects of these changes are major challenges.

This statement of the World Allergy Organization (WAO) raises the importance of this health hazard and highlights the facts on climate-related health impacts, including: deaths and acute morbidity due to heat waves and extreme meteorological events; increased frequency of acute cardio-respiratory events due to higher concentrations of ground level ozone; changes in the frequency of respiratory diseases due to trans-boundary particle pollution; altered spatial and temporal distribution of allergens (pollens, molds, and mites); and some infectious disease vectors. According to this report, these impacts will not only affect those with current asthma but also increase the incidence and prevalence of allergic respiratory conditions and of asthma. The effects of climate change on respiratory allergy are still not well defined, and more studies addressing this topic are needed. Global warming is expected to affect the start, duration, and intensity of the pollen season on the one hand, and the rate of asthma exacerbations due to air pollution, respiratory infections, and/or cold air inhalation, and other conditions on the other hand.

Associations between ozone, PM2.5, and four pollen types on emergency department pediatric asthma events during the warm season in New Jersey: a case-crossover study

BACKGROUND

Asthma is one of the most common chronic diseases among school-aged children in the United States. Environmental respiratory irritants exacerbate asthma among children. Understanding the impact of a variety of known and biologically plausible environmental irritants and triggers among children in New Jersey - ozone, fine particulate matter (PM2.5), tree pollen, weed pollen, grass pollen and ragweed - would allow for informed public health interventions.

METHODS

Time-stratified case-crossover design was used to study the transient impact of ozone, PM2.5 and pollen on the acute onset of pediatric asthma. Daily emergency department visits were obtained for children aged 3-17 years with a primary diagnosis of asthma during the warm season (April through September), 2004-2007 (inclusive). Bi-directional control sampling was used to select two control periods for each case for a total of 65,562 inclusion days. Since the period of exposure prior to emergency department visit may be the most clinically relevant, lag exposures were investigated (same day (lag0), 1, 2, 3, 4, and 5 as well as 3-day and 5-day moving averages). Multivariable conditional logistic regression controlling for holiday, school-in-session indicator, and 3-day moving average for temperature and relative humidity was used to examine the associations. Odds ratios are based on interquartile range (IQR) increases or 10 unit increases when IQR ranges were narrow. Single-pollutant models as well as multipollutant models were examined. Stratification on gender, race, ethnicity and socioeconomic status was explored.

RESULTS

The associations with ozone and PM2.5 were strongest on the same day (lag0) of the emergency department visit (RR IQR=1.05, 95% CI 1.04-1.06) and (RR IQR=1.03, 95% CI 1.02-1.04), respectively, with a decreasing lag effect. Tree and weed pollen were associated with pediatric ED visits; the largest magnitudes of association was with the 5-day average (RR IQR=1.23, 95% CI 1.21-1.25) and (RR 10=1.13, 95% CI 1.12-1.14), respectively. Grass pollen was only minimally associated with the outcome while ragweed had a negative association.

CONCLUSIONS

The ambient air pollutant ozone is associated with increases in pediatric emergency department asthma visits during the warm weather season. The different pollen types showed different associations with the outcome. High levels of tree pollen appear to be an important risk factor in asthma exacerbations.

Monitoring impacts of air pollution: PIXE analysis and histopathological modalities in evaluating relative risks of elemental contamination

Environmental toxicants invariably affect all biological organisms resulting to sufferings ranging from subclinical to debilitating clinical conditions. This novel research aimed to determine the toxic burdens of increased environmental elements in some vital organs/tissues of the wild animals (starling, owl, crow and pigeon), exposed to air polluted environment were assessed using particle induced X-ray emission and histopathological approaches. The presence of significantly elevated amounts of elemental toxicants namely: Aluminum (Al), Chlorine (Cl), Iron (Fe), Potassium (K), Magnesium (Mg), Manganese (Mn), Silicon (Si) and Vanadium (V) from the skin, muscle, lungs, liver and kidney of sampled animals were in concurrence with the observed histopathological changes. The skin of sampled starling, owl, pigeon and crow spotlighted highly significant increase (P < 0.001) in Al, Cl, Mg and Si. Muscle samples with myodegenerative lesions and mineral depositions highlighted substantial augmentation (P < 0.001) in the amount of Al, Fe, Mn, Si and V. The lungs of starling, owl, and pigeon were severely intoxicated (P < 0.001) with increased amount of Al, Fe, K, Mn and Si producing pulmonary lesions of congestion, edema, pneumonitis and mineral debris depositions. Liver samples revealed that the sampled animals were laden with Cl, Fe, Mg, Mn and V with histopathological profound degenerative changes and hepatic necrosis. Kidney sections presented severe tubular degenerative and necrotic changes that may be attributed to increased amounts of Cl and Fe. These current findings implied that the environmental/elemental toxicants and the accompanying lesions that were discerned in the organs/tissues of sampled birds may as well be afflicting people living within the polluted area. Further assessment to more conclusively demonstrate correlations of current findings to those of the populace within the area is encouraged.

Oxidation and nitration of tyrosine by ozone and nitrogen dioxide: reaction mechanisms and biological and atmospheric implications

The nitration of tyrosine by atmospheric oxidants, O3 and NO2, is an important cause for the spread of allergenic diseases. In the present study, the mechanism and pathways for the reaction of tyrosine with the atmospheric oxidants O3 and NO2 are studied using DFT-M06-2X, B3LYP, and B3LYP-D methods with the 6-311+G(d,p) basis set. The energy barrier for the initial oxidation reactions is also calculated at the CCSD(T)/6-31+G(d,p) level of theory. The reaction is studied in gas, aqueous, and lipid media. The initial oxidation of tyrosine by O3 proceeds by H atom abstraction and addition reactions and leads to the formation of six different intermediates. The subsequent nitration reaction is studied for all the intermediates, and the results show that the nitration affects both the side chain and the aromatic ring of tyrosine. The rate constant of the favorable oxidation and nitration reaction is calculated using variational transition state theory over the temperature range of 278-350 K. The spectral properties of the oxidation and nitration products are calculated at the TD-M06-2X/6-311+G(d,p) level of theory. The fate of the tyrosine radical intermediate is studied by its reaction with glutathione antioxidant. This study provides an enhanced understanding of the oxidation and nitration of tyrosine by O3 and NO2 in the context of improving the air quality and reducing the allergic diseases.

Personal exposure of primary school children to BTEX, NO₂ and ozone in Eskişehir, Turkey: relationship with indoor/outdoor concentrations and risk assessment

Personal exposures of 65 primary school children to benzene, toluene, ethyl benzene, xylenes (BTEX), nitrogen dioxide (NO2) and ozone (O3) were measured during 24h by using organic vapor monitors and tailor-made passive samplers. Two schools were selected to represent students living in more polluted (urban) and less polluted (sub-urban) areas in the city of Eskişehir, Turkey. The pollutant concentrations were also measured in indoor and outdoor environments during the personal sampling to investigate the contribution of each micro-environment on measured personal concentrations. Socio-demographic and personal time-activity data were collected by means of questionnaires and half-hour-time resolution activity diaries. Personal exposure concentrations were found to be correlated with indoor home concentrations. Personal, indoor and outdoor concentrations of all studied pollutants except for ozone were found to be higher for the students living at the urban traffic site. Ozone, on the other hand, had higher concentrations at the sub-urban site for all three types of measurements (personal, indoor and outdoor). Analysis of the questionnaire data pointed out to environmental tobacco smoke, use of solvent based products, and petrol station nearby as factors that affect personal exposure concentrations. Cancer and non-cancer risks were estimated using the personal exposure concentrations. The mean cancer risk for the urban school children (1.7×10(-5)) was found to be higher than the sub-urban school children (0.88×10(-5)). Children living with smoking parents had higher risk levels (1.7×10(-5)) than children living with non-smoking parents (1.08×10(-5)). Overall, the risk levels were <1×10(-4). All hazard quotient values for BTEX for the non-cancer health effects were <1 based on the calculations EPA's Risk Assessment Guidance for Superfund (RAGS) part F.

Separate and joint effects of tranplacental and postnatal inhalatory exposure to polycyclic aromatic hydrocarbons: prospective birth cohort study on wheezing events

The goal of this epidemiologic investigation was to analyze the associations between prenatal and postnatal exposure to airborne polycyclic aromatic hydrocarbons (PAH) and severity of wheeze and recurrent wheeze. The 257 children included in this analysis had a complete set of prenatal and postnatal PAH measurements and attended regular health checkups over a 4-year follow-up period since birth. Transplacental PAH exposure was measured by personal air monitoring of the mothers during the second trimester of pregnancy; postnatal exposure was estimated using the same instruments indoors at the children's residences at age 3. Chemical analysis tests were performed to determine airborne concentrations of nine PAH compounds. The results show that both prenatal and postnatal exposure were associated positively with the severity of wheezing days and recurrent wheezing reported in the follow-up. While the incidence rate ratio (IRR) for severity of wheeze and prenatal PAH exposure was 1.53 (95%CI: 1.43-1.64) that for postnatal PAH exposure was 1.13 (95%CI: 1.08-1.19). However, recurrent wheezing was more strongly associated with airborne PAH levels measured at age 3 (OR = 2.31, 95%CI: 1.26-4.22) than transplacental PAH exposure (OR = 1.40, 95% CI: 0.85-2.09), but the difference was statistically insignificant. In conclusion, it appears that prenatal PAH exposure may precipitate and intensify early onset of wheezing symptoms in childhood, resulting from the postnatal exposure and suggest that success in reducing the incidence of respiratory diseases in children would depend on reducing both fetal and childhood exposure to air pollution.

The level of control of mild asthma in general practice: an observational community-based study

OBJECTIVE

The aim of the present community-based study was to evaluate the level of asthma control in patients with mild asthma, regularly treated with inhaled steroids (ICS).

METHOD

This observational cross-sectional study included patients registered in the general practitioner (GP) database and with at least three prescriptions of ICS in the last 12 months. Patients were asked to refer to the doctor's office for a standardised interview. The level of asthma control was self-measured by the patients using the Asthma Control Test (ACT)™ (Quality Metric, Inc.).

RESULTS

The study included 950 asthmatic patients, referred by 540 GPs: 54.5% were females, mean age was 51 (±19.1) years; 59.5% were non-smokers, 22.5% were current smokers and 18.0% were former smokers; 81.1% of the patients were on ICS in the last 4 weeks. Only 38.6% of patients had a spirometry in the last 12 months. According to the ACT, 13.7% of the asthmatic patients were totally controlled, 51.0% well controlled, and 35.3% poorly controlled. Smoking habit, older age (>60) and living in Central or Southern Italy were associated with poorer control. In the last 12 months 4.5% of patients had an asthma-related hospitalisation, 5.3% an emergency visit and 18.9% a specialist visit.

CONCLUSIONS

More than one of three patients had poor asthma control, despite being considered by their GPs as mild asthmatics and treated with ICS. Asthmatic patients need to be regularly re-evaluated. Treatment is often inadequate and should be targeted to improve control and reduce asthma morbidity (SAM104964).

Streamer discharge reduces pollen-induced inflammatory responses and injury in human airway epithelial cells

Although epidemiological studies have demonstrated that cedar pollen influences respiratory health, effective method for inactivating cedar pollen has not been established. Streamer discharge is a type of plasma discharge in which high-speed electrons collide with oxygen and nitrogen molecules. It reportedly has the ability to eliminate bacteria, mould, chemical substances and allergens. The present study investigated the influence of pollen on BEAS-2B cell line, derived from human airway epithelial cells, as well as the efficiency of streamer discharge on pollen-induced health effects. Airway epithelial cells were exposed to non-treated pollen and streamer-discharged pollen at doses of 100 and 1000 μg/mL for 6 or 24 h. Non-treated pollen at a dose of 1000 μg/mL significantly decreased cell viability and induced both mRNA and protein expression of interleukin-6, whereas streamer-discharged pollen showed the attenuated changes as compared with non-treated pollen. Further, scanning electron micrographs showed that streamer discharge caused the fine structural changes of pollen. These results provide the first experimental evidence that pollen at a high dose affects cell viability and inflammatory responses, and streamer discharge technology attenuates their influences by decomposing pollen.

Evaluation of the effect of pollution and fungal disease on Pinus radiata pollen allergenicity

BACKGROUND

Pollutants and other stressing factors like mold infection might increase the production of pathogen-related proteins in plants. Since this is invoked as one of the causes for the high prevalence of allergic diseases in developed countries, we aimed to determine the potential effect of environmental pollution, with or without mold infection of the trees, on the allergenic potency of pine pollen (Pinus radiata).

METHODS

Pine pollen samples were recovered from three selected areas: low polluted (A), highly polluted (B) and highly polluted and infected with fungi (Spheropsis sapinea) (C). The allergenic potency of pollen from areas A, B or C were compared in vivo in 35 pine pollen-allergic patients by skin prick test and specific IgE (sIgE) quantification. Pollen was also analyzed in vitro by SDS-PAGE immunoblotting, RAST inhibition and cDNA-AFLP (amplified fragment length polymorphism) to compare differences in proteins and mRNA expression.

RESULTS

The allergenic potency measured by prick test, sIgE and RAST inhibition was greater in pollen A, which was exposed to smaller amounts of NO(x), PM(10) and SO(2) but greater amounts of O(3). No differences were found in IgE-binding bands in immunoblotting or densitometry of the bands. In cDNA-AFLP, three homologous transcript-derived fragments were expressed in samples B only, with an expressed sequence tag related with stress-regulated gene expression.

CONCLUSIONS

A greater allergenic potency, in terms of skin tests and sIgE, is observed in pine pollen coming from unpolluted areas. We consider that this fact might be related to a higher exposure to ozone, resulting in a greater expression of allergenic proteins.

A PDA-based Network for Telemonitoring Asthma Triggering Gases in the El Paso School Districts of the US - Mexico Border Region

In this paper we describe the application of a personal digital assistant (PDA) or pocket PC as an effective communication device to telemonitor levels of asthma triggering gases collected from a remote location under test to a workstation which has a personal computer (PC) running on Windows XP&#174; as the operating system. The Bluetooth&#174; features of the PDA are explored to transmit data collected by a Direct&#8482; Sense Tox toxic gas monitor equipped with five toxic gas probes and one temperature sensor in real time, thereby making this telemonitoring system an innovative instrument in monitoring levels of asthma triggering gases in the El Paso-border metropolitan region, a region in which asthma is highly prevalent especially in children. At the workstation or fixed location these readings are displayed using a custom made, user friendly graphical user interface (GUI) developed using software tools like action scripting with Macromedia&#174; Flash&#8482;. The growing advancement in technology and ever diminishing sizes of handheld devices encouraged us to opt for this configuration. Moreover, the PDA and toxic gas monitor were also chosen for their light weight, portability, flexibility, low cost and data collection and transmission capabilities.

Is the asthma epidemic still ascending?

Asthma is a phenotypically heterogeneous disorder of multifactorial origins that affects 300 million people suffering from asthma and more than 250,000 asthma-related deaths each year. Although treatment for asthma has improved, its prevalence continues to increase, particularly in low and middle income countries, or in some ethnic groups in which prevalence was previously low. Observed spatio-temporal variations in the increased prevalence of asthma depend on exposure to environmental factors. Recently, several arguments are also in favor of the involvement of host susceptibility and stress in the observed increase of asthma prevalence. Further investigations are warranted to better understand mechanisms underlying asthma increase or stagnation.

Thirty-year survey on airborne pollen concentrations in Genoa, Italy: relationship with sensitizations, meteorological data, and air pollution

BACKGROUND

Pollen allergy represents a relevant health issue. Betulaceae sensitization significantly increased in Genoa, Italy, in the last decades. This study investigated possible relationships among pollen count, meteorological changes, air pollution, and sensitizations in this city during a 30-year period.

METHODS

Betulaceae, Urticaceae, Gramineae, and Oleaceae pollen counts were measured from 1981 to 2010 in Genoa. Sensitization to these pollens was also considered in large populations of allergic patients. Meteorological parameters and pollutants were also measured in the same area.

RESULTS

Betulaceae sensitization increased over time. All pollen species significantly increased over this time. Pollen season advanced for Betulaceae and Urticaceae. Only Urticaceae season significantly increased. Temperature increased while rainfall decreased over the time. Pollutants significantly decreased. There were some relationships between pollen changes and climatic and air pollution parameters.

CONCLUSION

This 30-year study conducted in an urbanized area provided evidence that Betulaceae sensitization significantly increased, pollen load significantly augmented, and climate and air pollution changed with a possible influence on pollen release.

Effects of climatic changes and urban air pollution on the rising trends of respiratory allergy and asthma

Over the past two decades there has been increasing interest in studies regarding effects on human health of climate changes and urban air pollution. Climate change induced by anthropogenic warming of the earth's atmosphere is a daunting problem and there are several observations about the role of urbanization, with its high levels of vehicle emissions and other pollutants, and westernized lifestyle with respect to the rising frequency of respiratory allergic diseases observed in most industrialized countries.There is also evidence that asthmatic subjects are at increased risk of developing exacerbations of bronchial obstruction with exposure to gaseous (ozone, nitrogen dioxide, sulfur dioxide) and particulate inhalable components of air pollution.A change in the genetic predisposition is an unlikely cause of the increasing frequency in allergic diseases because genetic changes in a population require several generations. Consequently, environmental factors such as climate change and indoor and outdoor air pollution may contribute to explain the increasing frequency of respiratory allergy and asthma. Since concentrations of airborne allergens and air pollutants are frequently increased contemporaneously, an enhanced IgE-mediated response to aeroallergens and enhanced airway inflammation could account for the increasing frequency of allergic respiratory diseases and bronchial asthma.Scientific societies such as the European Academy of Allergy and Clinical Immunology, European Respiratory Society and the World Allergy Organization have set up committees and task forces to produce documents to focalize attention on this topic, calling for prevention measures.

Projections of the effects of climate change on allergic asthma: the contribution of aerobiology

Climate change is unequivocal and represents a possible threat for patients affected by allergic conditions. It has already had an impact on living organisms, including plants and fungi with current scenarios projecting further effects by the end of the century. Over the last three decades, studies have shown changes in production, dispersion and allergen content of pollen and spores, which may be region- and species-specific. In addition, these changes may have been influenced by urban air pollutants interacting directly with pollen. Data suggest an increasing effect of aeroallergens on allergic patients over this period, which may also imply a greater likelihood of the development of an allergic respiratory disease in sensitized subjects and exacerbation of symptomatic patients. There are a number of limitations that make predictions uncertain, and further and specifically designed studies are needed to clarify current effects and future scenarios. We recommend: More stress on pollen/spore exposure in the diagnosis and treatment guidelines of respiratory and allergic diseases; collection of aerobiological data in a structured way at the European level; creation, promotion and support of multidisciplinary research teams in this area; lobbying the European Union and other funders to finance this research.

Prevalence of rhinitis-related symptoms in Latin American children - results of the International Study of Asthma and Allergies in Childhood (ISAAC) phase three

The aim of this study was to evaluate the prevalence of rhinitis-related symptoms among children living in different parts of Latin America (LA) considering all centers involved in ISAAC Phase Three (Ph3). 93,851 children (6-7 yr-old) from 35 centers in 14 LA countries and 165,917 adolescents (13-14 yr-old) from 56 centers in 17 LA countries were enrolled. The mean prevalence rate of current rhinoconjunctivitis was 12.7% and ranged from 5.5% in Rosario City (Argentina) to 21.2% in Caracas (Venezuela) for the schoolchildren. The mean prevalence rate of current rhinoconjunctivitis was 18.5% and ranged from 7.1% in Cuernavaca (México) to 45.1% in Asunción (Paraguay) for the adolescents. These indexes were among the higher observed during ISAAC Ph3. In general the prevalence of rhinitis-related symptoms was higher among the Spanish speaking centers. Environmental risk factors must be evaluated in order to explain the differences observed even in centers from the same country.

Undertreatment of allergy: exploring the utility of sublingual immunotherapy

Allergic syndromes are highly prevalent and are comprised of a wide variety of clinical problems, including rhinitis, conjunctivitis, atopic dermatitis and urticaria, asthma, and food allergies. Numerous studies have shown that allergic syndromes are both underdiagnosed and undertreated. This is related to many factors, including trivialization of allergic conditions by physicians and patients, failure to adhere to diagnostic and treatment guidelines, and dissatisfaction with conventional pharmacologic treatments. Immunotherapy involves the administration of allergen extracts in an attempt to induce immunologic tolerance and has been used for the treatment of allergic syndromes and the prevention of long-term complications. Conventional subcutaneous immunotherapy is effective but is also associated with a risk of serious adverse events, requires administration by a trained health care professional, and is contraindicated in certain populations. By contrast, sublingual immunotherapy has been used extensively in Europe and possesses most of the benefits of subcutaneous immunotherapy along with increased safety, tolerability, and convenience. This narrative review explores data from selected clinical studies and concludes that sublingual immunotherapy may be well suited to fill the gap posed by the undertreatment of allergic syndromes in the United States.

Association of Atopy to Asthma Severity and Medication Use in Children

The importance of aeroallergens as triggers for asthma is well recognized, but the relationship between asthma severity and atopic profiles in childhood has not been elucidated. This study assessed the relationship of allergen sensitization to asthma severity in a study of 114 asthmatic children followed for 8 weeks in three Southern California areas. Increased controller medication and beta-agonist use were positively associated with number of positive skin tests and allergy to mold and pollens. Mold was associated with increased asthma symptoms. Degree of atopy and reactivity to mold and pollens plays a significant role in asthma severity in asthmatic children.