From 2007 to 2013, the globally averaged mole fraction of methane in the atmosphere increased by 5.7 ± 1.2 ppb yr−1. Simultaneously, δ13CCH4 (a measure of the 13C/12C isotope ratio in methane) has ...shifted to significantly more negative values since 2007. Growth was extreme in 2014, at 12.5 ± 0.4 ppb, with a further shift to more negative values being observed at most latitudes. The isotopic evidence presented here suggests that the methane rise was dominated by significant increases in biogenic methane emissions, particularly in the tropics, for example, from expansion of tropical wetlands in years with strongly positive rainfall anomalies or emissions from increased agricultural sources such as ruminants and rice paddies. Changes in the removal rate of methane by the OH radical have not been seen in other tracers of atmospheric chemistry and do not appear to explain short‐term variations in methane. Fossil fuel emissions may also have grown, but the sustained shift to more 13C‐depleted values and its significant interannual variability, and the tropical and Southern Hemisphere loci of post‐2007 growth, both indicate that fossil fuel emissions have not been the dominant factor driving the increase. A major cause of increased tropical wetland and tropical agricultural methane emissions, the likely major contributors to growth, may be their responses to meteorological change.
Plain Language Summary
Atmospheric methane, which is a powerful greenhouse gas, is increasing rapidly. In the 20th century, methane growth was primarily driven by emissions from fossil fuel sources, such as the natural gas industry and coal mining. Then, in the early years of the 21st century, came a period of stability in methane. However, since 2007, growth has resumed, with especially strong growth in 2014. Evidence from carbon isotopes implies that the primary cause of the new growth is an increase in biogenic emissions, probably from wetlands and also agricultural sources, such as rice fields and cattle. The evidence presented in this research study, from a wide range of measurement sites both in the northern and southern hemispheres, suggests increased tropical emissions, for example from tropical wetlands, may be a principal cause of the global rise in methane. Contributions to the growth may also come from agricultural sources and perhaps some fossil fuel emissions also.
Key Points
Atmospheric methane is growing rapidly
Isotopic evidence implies that the growth is driven by biogenic sources
Growth is dominated by tropical sources
Skin prick testing is the standard for diagnosing IgE-mediated allergies. A positive skin prick reaction, however, does not always correlate with clinical symptoms. A large database from a Global ...Asthma and Allergy European Network (GA²LEN) study with data on clinical relevance was used to determine the clinical relevance of sensitizations against the 18 most frequent inhalant allergens in Europe. The study population consisted of patients referred to one of the 17 allergy centres in 14 European countries (n = 3034, median age = 33 years). The aim of the study was to assess the clinical relevance of positive skin prick test reactions against inhalant allergens considering the predominating type of symptoms in a pan-European population of patients presenting with suspected allergic disease. Clinical relevance of skin prick tests was recorded with regard to patient history and optional additional tests. A putative correlation between sensitization and allergic disease was assessed using logistic regression analysis. While an overall rate of greater-than-or-equal60% clinically relevant sensitizations was observed in all countries, a differential distribution of clinically relevant sensitizations was demonstrated depending on type of allergen and country where the prick test was performed. Furthermore, a significant correlation between the presence of allergic disease and the number of sensitizations was demonstrated. This study strongly emphasizes the importance of evaluating the clinical relevance of positive skin prick tests and calls for further studies, which may, ultimately, help increase the positive predictive value of allergy testing.
Atmospheric methane grew very rapidly in 2014 (12.7 ± 0.5 ppb/year), 2015 (10.1 ± 0.7 ppb/year), 2016 (7.0 ± 0.7 ppb/year), and 2017 (7.7 ± 0.7 ppb/year), at rates not observed since the 1980s. The ...increase in the methane burden began in 2007, with the mean global mole fraction in remote surface background air rising from about 1,775 ppb in 2006 to 1,850 ppb in 2017. Simultaneously the 13C/12C isotopic ratio (expressed as δ13CCH4) has shifted, now trending negative for more than a decade. The causes of methane's recent mole fraction increase are therefore either a change in the relative proportions (and totals) of emissions from biogenic and thermogenic and pyrogenic sources, especially in the tropics and subtropics, or a decline in the atmospheric sink of methane, or both. Unfortunately, with limited measurement data sets, it is not currently possible to be more definitive. The climate warming impact of the observed methane increase over the past decade, if continued at >5 ppb/year in the coming decades, is sufficient to challenge the Paris Agreement, which requires sharp cuts in the atmospheric methane burden. However, anthropogenic methane emissions are relatively very large and thus offer attractive targets for rapid reduction, which are essential if the Paris Agreement aims are to be attained.
Plain Language Summary
The rise in atmospheric methane (CH4), which began in 2007, accelerated in the past 4 years. The growth has been worldwide, especially in the tropics and northern midlatitudes. With the rise has come a shift in the carbon isotope ratio of the methane. The causes of the rise are not fully understood, and may include increased emissions and perhaps a decline in the destruction of methane in the air. Methane's increase since 2007 was not expected in future greenhouse gas scenarios compliant with the targets of the Paris Agreement, and if the increase continues at the same rates it may become very difficult to meet the Paris goals. There is now urgent need to reduce methane emissions, especially from the fossil fuel industry.
Key Points
Atmospheric methane is rising; its carbon isotopic ratio has become more depleted in C‐13
The possible causes of the change include an increase in emissions, with changing relative proportions of source inputs, or a decline in methane destruction, or both
If this rise continues, there are significant consequences for the UN Paris Agreement
To cite this article: Jarvis D, Newson R, Lotvall J, Hastan D, Tomassen P, Keil T, Gjomarkaj M, Forsberg B, Gunnbjornsdottir M, Minov J, Brozek G, Dahlen SE, Toskala E, Kowalski ML, Olze H, Howarth ...P, Krämer U, Baelum J, Loureiro C, Kasper L, Bousquet PJ, Bousquet J, Bachert C, Fokkens W, Burney P. Asthma in adults and its association with chronic rhinosinusitis: The GA2LEN survey in Europe. Allergy 2012; 67: 91–98.
Background: The prevalence of asthma and its association with chronic rhinosinusitis (CRS) have not been widely studied in population‐based epidemiological surveys.
Methods: The Global Allergy and Asthma Network of Excellence (GA2LEN) conducted a postal questionnaire in representative samples of adults living in Europe to assess the presence of asthma and CRS defined by the European Position Paper on Rhinosinusitis and Nasal Polyps. The prevalence of self‐reported current asthma by age group was determined. The association of asthma with CRS in each participating centre was assessed using logistic regression analyses, controlling for age, sex and smoking, and the effect estimates were combined using standard methods of meta‐analysis.
Results: Over 52 000 adults aged 18–75 years and living in 19 centres in 12 countries took part. In most centres, and overall, the reported prevalence of asthma was lower in older adults (adjusted OR for 65–74 years compared with 15–24 years: 0.72; 95% CI: 0.63–0.81). In all centres, there was a strong association of asthma with CRS (adjusted OR: 3.47; 95% CI: 3.20–3.76) at all ages. The association with asthma was stronger in those reporting both CRS and allergic rhinitis (adjusted OR: 11.85; 95% CI: 10.57–13.17). CRS in the absence of nasal allergies was positively associated with late‐onset asthma.
Conclusion: Geographical variation in the prevalence of self‐reported asthma was observed across Europe, but overall, self‐reported asthma was more common in young adults, women and smokers. In all age groups, men and women, and irrespective of smoking behaviour, asthma was also associated with CRS.
To cite this article: Ohta K, Bousquet P‐J, Aizawa H, Akiyama K, Adachi M, Ichinose M, Ebisawa M, Tamura G, Nagai A, Nishima S, Fukuda T, Morikawa A, Okamoto Y, Kohno Y, Saito H, Takenaka H, Grouse ...L, Bousquet J. Prevalence and impact of rhinitis in asthma: SACRA, a cross‐sectional nation‐wide study in Japan. Allergy 2011; 66: 1287–1295.
Background: Asthma and rhinitis are common co‐morbidities everywhere in the world but nation‐wide studies assessing rhinitis in asthmatics using questionnaires based on guidelines are not available.
Objective: To assess the prevalence, classification, and severity of rhinitis using the Allergic Rhinitis and its Impact on Asthma (ARIA) criteria in Japanese patients with diagnosed and treated asthma.
Methods: The study was performed from March to August 2009. Patients in physicians’ waiting rooms, or physicians themselves, filled out questionnaires on rhinitis and asthma based on ARIA and Global Initiative for Asthma (GINA) diagnostic guides. The patients answered questions on the severity of the diseases and a Visual Analog Scale. Their physicians made the diagnosis of rhinitis.
Results: In this study, 1910 physicians enrolled 29 518 asthmatics; 15 051 (51.0%) questionnaires were administered by physician, and 26 680 (90.4%) patients were evaluable. Self‐ and physician‐administered questionnaires gave similar results. Rhinitis was diagnosed in 68.5% of patients with self‐administered questionnaires and 66.2% with physician‐administered questionnaires. In this study, 994 (7.6%) patients with self‐administered and 561 (5.2%) patients with physician‐administered questionnaires indicated rhinitis symptoms on the questionnaires without a physician’s diagnosis of rhinitis. Most patients with the physician’s diagnosis of rhinitis had moderate/severe rhinitis. Asthma control was significantly impaired in patients with a physician’s diagnosis of rhinitis for all GINA clinical criteria except exacerbations. There were significantly more patients with uncontrolled asthma as defined by GINA in those with a physician’s diagnosis of rhinitis (25.4% and 29.7%) by comparison with those without rhinitis (18.0% and 22.8%).
Conclusion: Rhinitis is common in asthma and impairs asthma control.
Hypersensitivity reactions to betalactams (BLs) are classified as immediate or nonimmediate. The former usually appear within 1 h of drug-intake and are mediated by specific IgE-antibodies. ...Nonimmediate reactions are those occurring more than 1 h after drug-intake, and they can be T-cell mediated. The diagnostic evaluation of allergic reactions to BLs has changed over the last 5 years, for several reasons. Major and minor determinants are no longer commercially available for skin testing in many countries. In immediate allergic reactions, the sensitivity of skin testing and immunoassays is decreasing and new in vitro methods, such as the basophil activation test, are gaining importance for diagnosis. For nonimmediate reactions, skin testing appears to be less sensitive than previous results, although more studies need to be carried out in this direction. Nevertheless, the drug provocation test is still necessary for diagnosis.
Background
Nonsteroidal anti‐inflammatory drugs (NSAIDs) are among the most prevalent drugs inducing hypersensitivity reactions. The aim of this analysis was to estimate the prevalence of ...NSAID‐induced respiratory symptoms in population across Europe and to assess its association with upper and lower respiratory tract disorders.
Methods
The GA2LEN survey was conducted in 22 centers in 15 European countries. Each of 19 centers selected random samples of 5000 adults aged 15–74 from their general population, and in three centers (Athens, Munich, Oslo), a younger population was sampled. Questionnaires including questions about age, gender, presence of symptoms of asthma, allergic rhinitis, chronic rhinosinusitis, smoking status, and history of NSAID‐induced hypersensitivity reactions were sent to participants by mail. Totally, 62 737 participants completed the questionnaires.
Results
The mean prevalence of NSAID‐induced dyspnea was 1.9% and was highest in the three Polish centers Katowice (4.9%), Krakow (4.8%), and Lodz (4.4%) and lowest in Skopje, (0.9%), Amsterdam (1.1%), and Umea (1.2%). In multivariate analysis, the prevalence of respiratory reactions to NSAIDs was higher in participants with chronic rhinosinusitis symptoms (Odds Ratio 2.12; 95%CI 1.78–2.74), asthma symptoms in last 12 months (2.7; 2.18–3.35), hospitalization due to asthma (1.53; 1.22–1.99), and adults vs children (1.53; 1.24–1.89), but was not associated with allergic rhinitis.
Conclusion
Our study documented significant variation between European countries in the prevalence of NSAID‐induced respiratory hypersensitivity reactions, and association with chronic airway diseases, but also with environmental factors.
To cite this article: Brożek JL, Akl EA, Compalati E, Kreis J, Terracciano L, Fiocchi A, Ueffing E, Andrews J, Alonso‐Coello P, Meerpohl JJ, Lang DM, Jaeschke R, Williams JW Jr, Phillips B, Lethaby ...A, Bossuyt P, Glasziou P, Helfand M, Watine J, Afilalo M, Welch V, Montedori A, Abraha I, Horvath AR, Bousquet J, Guyatt GH, Schünemann HJ, for the GRADE Working Group. Grading quality of evidence and strength of recommendations in clinical practice guidelines. Part 3 of 3. The GRADE approach to developing recommendations. Allergy 2011; 66: 588–595.
This is the third and last article in the series about the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to grading the quality of evidence and the strength of recommendations in clinical practice guidelines and its application in the field of allergy. We describe the factors that influence the strength of recommendations about the use of diagnostic, preventive and therapeutic interventions: the balance of desirable and undesirable consequences, the quality of a body of evidence related to a decision, patients’ values and preferences, and considerations of resource use. We provide examples from two recently developed guidelines in the field of allergy that applied the GRADE approach. The main advantages of this approach are the focus on patient important outcomes, explicit consideration of patients’ values and preferences, the systematic approach to collecting the evidence, the clear separation of the concepts of quality of evidence and strength of recommendations, and transparent reporting of the decision process. The focus on transparency facilitates understanding and implementation and should empower patients, clinicians and other health care professionals to make informed choices.
Background: The prevalence of asthma and its association with chronic rhinosinusitis (CRS) have not been widely studied in population-based epidemiological surveys.
Methods: The Global Allergy and ...Asthma Network of Excellence (GA 2 LEN) conducted a postal questionnaire in representative samples of adults living in Europe to assess the presence of asthma and CRS defined by the European Position Paper on Rhinosinusitis and Nasal Polyps. The prevalence of self-reported current asthma by age group was determined. The association of asthma with CRS in each participating centre was assessed using logistic regression analyses, controlling for age, sex and smoking, and the effect estimates were combined using standard methods of meta-analysis.
Results: Over 52 000 adults aged 18–75 years and living in 19 centres in 12 countries took part. In most centres, and overall, the reported prevalence of asthma was lower in older adults (adjusted OR for 65–74 years compared with 15–24 years: 0.72; 95% CI: 0.63–0.81). In all centres, there was a strong association of asthma with CRS (adjusted OR: 3.47; 95% CI: 3.20–3.76) at all ages. The association with asthma was stronger in those reporting both CRS and allergic rhinitis (adjusted OR: 11.85; 95% CI: 10.57–13.17). CRS in the absence of nasal allergies was positively associated with late-onset asthma.
Conclusion: Geographical variation in the prevalence of self-reported asthma was observed across Europe, but overall, self-reported asthma was more common in young adults, women and smokers. In all age groups, men and women, and irrespective of smoking behaviour, asthma was also associated with CRS.
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