Intergenerational 20 year trends in the prevalence of asthma and hay fever in adults: the Midspan family study surveys of parents and offspring

Mycobacterium vaccae protects against glucocorticoid resistance resulting from combined physical and psychosocial trauma in mice

Stress-related somatic and psychiatric disorders are often associated with a decline in regulatory T cell (Treg) counts and chronic low-grade inflammation. Recent preclinical evidence suggests that the latter is at least partly mediated by stress-induced upregulation of toll-like receptor (TLR)2 in newly generated neutrophils and polymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs), as well as glucocorticoid (GC) resistance in predominantly PMN-MDSCs following stress-induced upregulation of TLR4 expression. Here we show in mice exposed to the chronic subordinate colony housing (CSC) paradigm that repeated intragastric (i.g.) administrations of a heat-killed preparation of Mycobacterium vaccae NCTC 11659, a saprophytic microorganism with immunoregulatory properties, protected against the stress-induced reduction in systemic Tregs, increase in basal and LPS-induced in vitro splenocyte viability, as well as splenic in vitro GC resistance. Our findings further support the hypothesis that i.g. M. vaccae protects against CSC-associated splenic GC resistance via directly affecting the myeloid compartment, thereby preventing the CSC-induced upregulation of TLR4 in newly generated PMN-MDSCs. In contrast, the protective effects of i.g. M. vaccae on the CSC-induced upregulation of TLR2 in neutrophils and the subsequent increase in basal and LPS-induced in vitro splenocyte viability seems to be indirectly mediated via the Treg compartment. These data highlight the potential for use of oral administration of M. vaccae NCTC 11659 to prevent stress-induced exaggeration of inflammation, a risk factor for development of stress-related psychiatric disorders.

Climate change, the environment, and rhinologic disease

BACKGROUND

The escalating negative impact of climate change on our environment has the potential to result in significant morbidity of rhinologic diseases.

METHODS

Evidence based review of examples of rhinologic diseases including allergic and nonallergic rhinitis, chronic rhinosinusitis, and allergic fungal rhinosinusitis was performed.

RESULTS

The lower socioeconomic population, including historically oppressed groups, will be disproportionately affected.

CONCLUSIONS

We need a systematic approach to improve healthcare database infrastructure and funding to promote diverse scientific collaboration to address these healthcare needs.

Impact of FOXP3 gene polymorphisms and gene-environment interactions in asthma and atopy in a Brazilian population

BACKGROUND

Polymorphisms in genes related to the activation and development of regulatory T cells (Tregs), such as FOXP3, may be associated with asthma and atopy development. Additionally, environmental factors such as exposure to infections can modify the effect of these associations. This study evaluated the impact of polymorphisms in the FOXP3 on the risk of asthma and atopy as also gene-environment interactions in these outcomes.

METHODS

This study included 1,246 children from the SCAALA program, between 4 and 11 years of age. DNA was extracted from peripheral blood and eight SNPs (rs2280883, rs11465476, rs11465472, rs2232368, rs3761549, rs3761548, rs2232365 and rs2294021) were genotyped using the 2.5 HumanOmni Beadchip from Illumina (San Diego, California, USA) or TaqMan qRT-PCR.

RESULTS

The rs2232368 (Allele T) was positively associated with asthma symptoms (OR=1.95, CI=1.04 to 3.66, p = 0.040) and skin prick test (SPT) reactivity to aeroallergens (OR=2.31, CI=1.16 to 4.59, p = 0.017). The rs3761549 (Allele T) was positively associated with SPT reactivity (OR=1.44, CI=1.03 to 2.02, p = 0.034). The rs2280883 (Allele C) was negatively associated with specific IgE to aeroallergens (OR=0.83, CI=0.70 to 0.99, p = 0.040). Furthermore, the rs2280883 played a protective role in the development of atopy only in individuals seropositive to Epstein-Barr virus (EBV) infection (OR=0.74, CI=0.60 to 0.92, p = 0.003 and OR=0.74; 95% CI=0.61-0.91, p = 0.007 for SPT and slgE respectively), but not in individuals without EBV infection.

CONCLUSION

Polymorphisms in the FOXP3 gene were associated with the risk of atopy and asthma development in our population. In addition, EBV infection had an effect modifier of the observed association for rs2280883 variant.

Worldwide prevalence of rhinitis in adults: A review of definitions and temporal evolution

Introduction

Objective

Methods

Results

Conclusions

Hospital admission trends due to respiratory diseases in England and Wales between 1999 and 2019: an ecologic study

BACKGROUND

Identifying trends of hospital admissions for respiratory diseases is crucial for public health and research to guide future clinical improvements for better outcomes. This study aims to define the trends of respiratory disease-related hospital admissions (RRHA) in England and Wales between 1999 and 2019.

METHODS

An ecological study was conducted using hospital admission data taken from the Hospital Episode Statistics database in England and the Patient Episode Database for Wales. Hospital admissions data for respiratory diseases were extracted for the period between April 1999 and March 2019. The trend in hospital admissions was assessed using a Poisson model.

RESULTS

Hospital admission rate increased by 104.7% [from 1535.05 (95% CI 1531.71-1538.38) in 1999 to 3142.83 (95% CI 3138.39-3147.26) in 2019 per 100,000 persons, trend test, p < 0.01]. The most common causes were influenza and pneumonia, chronic lower respiratory diseases, other acute lower respiratory infections, which accounted for 26.6%, 26.4%, and 14.9%, respectively. The age group 75 years and above accounted for 34.1% of the total number of hospital admissions. Males contributed to 50.5% of the total number of hospital admissions. Hospital admission rate in females increased by 119.8% [from 1442.18 (95% CI 1437.66-1446.70) in 1999 to 3169.38 (95% CI 3163.11-3175.64) in 2019 per 100,000 persons, trend test, p < 0.001]. Hospital admission rate increased by 92.9% in males [from 1633.25 (95% CI 1628.32-1638.17) in 1999 to 3149.78 (95% CI 3143.46-3156.09) in 2019 per 100,000 persons, trend test, p < 0.001].

CONCLUSION

During the study period, hospital admissions rate due to respiratory diseases increased sharply. The rates of hospital admissions were higher among males for the vast majority of respiratory diseases. Further observational studies are warranted to identify risk factors for these hospital admissions and to offer relevant interventions to mitigate the risk.

Low-affinity but high-avidity interactions may offer an explanation for IgE-mediated allergen cross-reactivity

Background

Allergy is a global disease with overall frequencies of >20%. Symptoms vary from irritating local itching to life‐threatening systemic anaphylaxis. Even though allergies are allergen‐specific, there is a wide range of cross‐reactivities (eg apple and latex) that remain largely unexplained. Given the abilities of low‐affinity IgG antibodies to inhibit mast cells activation, here we elucidate the minimal affinity of IgE antibodies to induce type I hypersensitivity.

Methods

Three mature (high‐affinity) IgE antibodies recognizing three distinct epitopes on Fel d 1, the major cat allergen, were back‐mutated to germline conformation, resulting in binding to Fel d 1 with low affinity. The ability of these IgE antibodies to activate mast cells in vitro and in vivo was tested.

Results

We demonstrate that affinities as low as 10⁻⁷ M are sufficient to activate mast cells in vitro and drive allergic reactions in vivo. Low‐affinity IgE antibodies are able to do so, since they bind allergens bivalently on the surface of mast cells, leading to high‐avidity interactions.

Conclusions

These results suggest that the underlying mechanism of allergen cross‐reactivity may be low‐affinity but high‐avidity binding between IgE antibodies and cross‐reactive allergen.

The role of CD23 in the regulation of allergic responses

IgE, the key molecule in atopy has been shown to bind two receptors, FcεRI, the high‐affinity receptor, and FcεRII (CD23), binding IgE with lower affinity. Whereas cross‐linking of IgE on FcεRI expressed by mast cells and basophils triggers the allergic reaction, binding of IgE to CD23 on B cells plays an important role in both IgE regulation and presentation. Furthermore, IgE‐immune complexes (IgE‐ICs) bound by B cells enhance antibody and T cell responses in mice and humans. However, the mechanisms that regulate the targeting of the two receptors and the respective function of the two pathways in inflammation or homeostasis are still a matter of debate. Here, we focus on CD23 and discuss several mechanisms related to IgE binding, as well as the impact of the IgE/antigen‐binding on different immune cells expressing CD23. One recent paper has shown that free IgE preferentially binds to FcεRI whereas IgE‐ICs are preferentially captured by CD23. Binding of IgE‐ICs to CD23 on B cells can, on one hand, regulate serum IgE and prevent effector cell activation and on the other hand facilitate antigen presentation by delivering the antigen to dendritic cells. These data argue for a multifunctional role of CD23 for modulating IgE serum levels and immune responses.

DC-targeted gold nanoparticles as an efficient and biocompatible carrier for modulating allergic responses in sublingual immunotherapy

BACKGROUND

Sublingual immunotherapy (SLIT) was introduced to deliver allergens in an effective and non-invasive route, which can be considered as an alternative for allergen-specific subcutaneous immunotherapy (SCIT). On the other hand, the use of gold nanoparticles (AuNPs) in allergen delivery has beneficial effects on sublingual immunotherapy. In addition, the molecular targeting agents like aptamers (Apt), have been widely applied for targeted drug delivery. Therefore, the current study aimed to evaluate the effects of dendritic cells (DCs)-specific Aptamer-modified AuNPs coated with ovalbumin (OVA) on the improvement of the SLIT outcome in the mouse model of allergy.

MATERIAL AND METHODS

AuNPs with approximately 15 nm diameter were prepared by citrate reduction of HAuCl4. Afterward, Apt-modified AuNP complex was prepared and OVA was then loaded onto this complex. Following sensitization of Balb/c mice to OVA, SLIT was performed with Apt-AuNPs containing 5 µg OVA twice a week for a 2-month period. Allergen-specific IgE in serum, as well as cytokines secretion of spleen cells, were analyzed using ELISA. Also, nasopharyngeal lavage Fluid (NALF) was collected for total and eosinophil counts. Moreover, the lungs were removed for histopathological examination.

RESULTS

SLIT with Apt-modified AuNPs complex containing 5 μg OVA, decreased the IgE levels compared to the other groups. Also, IL-4 production has significantly decreased in spleen cells, while TGF-β and IFN-γ have significantly increased. The assessment of NALF in the group treated by this complex showed a decrease in total cell as well as in eosinophil count. Also, the examination of lung tissues revealed that, in the group treated by this complex, inflammation and perivascular infiltration were lesser than the other groups, which were observed in only one vessel of tissue.

CONCLUSION

It was shown that, Sublingual immunotherapy with DC specific Apt-modified AuNPs containing 5 μg OVA can improve the Th1 and Treg immunomodulatory responses.

Change in the symptom profile treated as asthma - two cross-sectional studies twenty years apart

AIMS

The aims of the study were to investigate prevalence trends of respiratory symptoms, asthma and asthma treatment among young adults in Estonia and to estimate changes in symptom profile among subjects who self-report asthma attacks or use asthma medications.

METHODS

Two similar questionnaires on respiratory health were sent to subjects in Tartu, Estonia, aged between 20 and 44 years; first in 1993/94, and then in 2014/15. To study the impact of different respiratory symptoms on asthma diagnosis and treatment, the log-binomial regression was used to estimate the association between 'attack of asthma' (as a proxy for current asthma) and respiratory symptoms as well as asthma treatment and respiratory symptoms, adjusted for age, sex and smoking history.

RESULTS

Self-reported prevalence of asthma attack, asthma medication use and nasal allergies increased over the twenty years between studies, whereas there was no change in prevalence of asthma-related symptoms, and the prevalence of most respiratory symptoms either decreased, or remained unchanged. For women experiencing asthma attacks, the prevalence of nasal allergies increased and waking with chest tightness decreased. For men using asthma medication, the prevalence of a wheeze without a cold decreased. Women using asthma medication reported decreased prevalence of waking with chest tightness.

CONCLUSION

Self-reported asthma attacks and asthma medication use has increased in last 20 years, while the prevalence of most respiratory symptoms either decreased or did not change. It is likely that changes in asthma symptom profile have had an impact on the prevalence of asthma and asthma treatment.

Changes in the prevalence of asthma and respiratory symptoms in western Sweden between 2008 and 2016

BACKGROUND

Asthma is a common chronic inflammatory disease of the airways, with a noticeable increase in prevalence during the second half of the 20th century. Recent studies assessing the prevalence trends among adults have been inconsistent. We investigated the changes in the prevalence of asthma, respiratory symptoms, and risk factors between 2008 and 2016 in western Sweden.

METHODS

The West Sweden Asthma Study (WSAS) is a population-based study which started in 2008 (WSAS I) and then repeated in 2016 (WSAS II) in western Sweden. Randomly selected individuals aged 16-75 years (N = 18 087 in 2008 and N = 24 534 in 2016) completed a questionnaire regarding obstructive lung diseases, respiratory symptoms, potential risk factors, and also questions from the GA² LEN survey.

RESULTS

The prevalence of reported ever asthma, physician-diagnosed asthma, use of asthma medication, and current asthma increased significantly from 9.6% to 11%, 8.3% to 10%, 8.6% to 9.8%, and 8.1% to 9.1%, respectively, between 2008 and 2016. There were also increases in the prevalence of respiratory symptoms during the same period. The greatest increase occurred in young adults aged 16-25 years. Female gender, allergic rhinitis, obesity, and family history of asthma remained the strongest risk factors for asthma in 2016 as it was in 2008.

CONCLUSION

There were moderate increases in asthma and respiratory symptoms in adults in western Sweden between 2008 and 2016, the greatest increase occurring in younger adults. The potential risk factors for asthma remained the same during the study period.

CD23 provides a noninflammatory pathway for IgE-allergen complexes

BACKGROUND

Type I hypersensitivity is mediated by allergen-specific IgE, which sensitizes the high-affinity IgE receptor FcεRI on mast cells and basophils and drives allergic inflammation upon secondary allergen contact. CD23/FcεRII, the low-affinity receptor for IgE, is constitutively expressed on B cells and has been shown to regulate immune responses. Simultaneous binding of IgE to FcεRI and CD23 is blocked by reciprocal allosteric inhibition, suggesting that the 2 receptors exert distinct roles in IgE handling.

OBJECTIVE

We aimed to study how free IgE versus precomplexed IgE-allergen immune complexes (IgE-ICs) target the 2 IgE receptors FcεRI and CD23, and we investigated the functional implications of the 2 pathways.

METHODS

We performed binding and activation assays with human cells in vitro and IgE pharmacokinetics and anaphylaxis experiments in vivo.

RESULTS

We demonstrate that FcεRI preferentially binds free IgE and CD23 preferentially binds IgE-ICs. We further show that those different binding properties directly translate to distinct biological functions: free IgE initiated allergic inflammation through FcεRI on allergic effector cells, while IgE-ICs were noninflammatory because of reduced FcεRI binding and enhanced CD23-dependent serum clearance.

CONCLUSION

We propose that IgE-ICs are noninflammatory through reduced engagement by FcεRI but increased targeting of the CD23 pathway.

Old Friends, immunoregulation, and stress resilience

There is a considerable body of evidence indicating that chronic adverse experience, especially chronic psychosocial stress/trauma, represents a major risk factor for the development of many somatic and affective disorders, including inflammatory bowel disease (IBD) and posttraumatic stress disorder (PTSD). However, the mechanisms underlying the development of chronic stress-associated disorders are still in large part unknown, and current treatment and prevention strategies lack efficacy and reliability. A greater understanding of mechanisms involved in the development and persistence of chronic stress-induced disorders may lead to novel approaches to prevention and treatment of these disorders. In this review, we provide evidence indicating that increases in immune (re-)activity and inflammation, potentially promoted by a reduced exposure to immunoregulatory microorganisms ("Old Friends") in today's modern society, may be causal factors in mediating the vulnerability to development and persistence of stress-related pathologies. Moreover, we discuss strategies to increase immunoregulatory processes and attenuate inflammation, as for instance contact with immunoregulatory Old Friends, which appears to be a promising strategy to promote stress resilience and to prevent/treat chronic stress-related disorders.

Low dose of chlorine exposure exacerbates nasal and pulmonary allergic inflammation in mice

Work-exacerbated asthma (WEA) is defined as preexisting asthma that worsens with exposure to irritants [e.g., chlorine (Cl₂) derivatives] in the workplace. The maximum allowable concentration in the workplace of Cl₂ exposure is 3 mg/ m³ (described in OSHA). We investigated in an experimental asthma model in mice the effects of a single exposure to a sodium hypochlorite dose with this allowed chlorine concentration and a tenfold higher dose. Acute chlorine exposure at 3.3 mg/m³ in the OVA-sensitized group increased eosinophils in the peribronquial infiltrate, cytokine production, nasal mucus production and the number of iNOS positive cells in the distal lung compared to only sensitized mice. The exposure to a higher dose of 33.3 mg/m³ in the OVA-sensitized group resulted in an increase in respiratory system elastance, in the total and differential numbers of inflammatory cells in bronchoalveolar lavage fluid, IL-4, IL-5, and IL-17 in the lungs, eosinophils in peribronquial infiltrate and mucus content in nasal compared to non-exposed and sensitized animals. In this asthma model, chorine exposures at an allowable dose, contributed to the potentiation of Th2 responses. The functional alterations were associated with increased iNOS and ROCK-2 activation in the distal lung.

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.

Allergens displayed on virus-like particles are highly immunogenic but fail to activate human mast cells

BACKGROUND

The goal of allergen-specific immunotherapy is the induction of protective immune responses in the absence of anaphylactic reactions. We have previously shown that Fel d 1, the major cat allergen, displayed in a repetitive fashion on virus-like particles (VLPs) may fulfill these criteria. Specifically, Fel d 1 on VLPs induced strongly increased protective IgG responses compared to free allergen in mice while anaphylactic reactions were essentially abolished. Here we extend these findings to human mast cells and offer a mechanistic explanation for the reduced anaphylactic activity.

METHODS

We differentiated human mast cells in vitro from blood-derived stem cell progenitors and sensitized the cells with a monoclonal Fel d 1-specific IgE. We compared the capability of Fel d 1 to induce mast cell activation in its free form versus displayed on VLPs and we performed allergen binding studies by surface plasmon resonance as well as flow cytometry.

RESULTS

We show that free Fel d 1 induces degranulation of IgE-sensitized mast cells whereas Fel d 1 displayed on VLPs fails to induce mast cell activation. We demonstrate that this inability to activate mast cells is based on a biophysical as well as a biochemical mechanism. Firstly, Fel d 1 on VLPs showed a strongly impaired ability to bind to surface-bound IgE. Secondly, despite residual binding, repetitively displayed allergen on VLPs failed to cause mast cell activation.

CONCLUSION

These findings indicate that repetitively displaying allergens on VLPs increases their immunogenicity while reducing their potential to cause anaphylactic reactions by essentially eliminating IgE-mediated activation of mast cells.

Enhanced efficacy of sublingual immunotherapy by liposome-mediated delivery of allergen

Immunotherapy by sublingual administration of allergens provides high patient compliance and has emerged as an alternative to subcutaneous immunotherapy for the treatment of IgE-associated allergic diseases. However, sublingual immunotherapy (SLIT) can cause adverse events. Development of allergen delivery systems enabling more efficient delivery and hence lower allergen load might reduce the adverse events. In the present study, we have investigated neutral and cationic liposomes as delivery systems of ovalbumin (OVA), as a model allergen, in an OVA-induced allergic airway inflammation model. We investigated the liposome carriers' ability to improve tolerance induction of antigens compared to the corresponding dose of free OVA. Mice were treated sublingually over 2 weeks with free or liposome encapsulated OVA followed by intraperitoneal injections and intranasal challenge. Mice sublingually treated with OVA-liposomes showed a significant reduction of airway eosinophilia and splenocyte proliferation in comparison to free OVA. A similar nonsignificant pattern was seen for OVA-specific IgE antibodies. In addition, reduced levels of interferon-γ and interleukin-5 were observed in spleen cell culture supernatants from OVA-liposome-treated mice compared to the sham-treated group. In conclusion, in vivo efficacy data showed that prophylactic SLIT with OVA-liposomes is significantly more effective in preventing allergic inflammation than the corresponding dose of free OVA.

Pharmacoeconomics of sublingual immunotherapy with the 5-grass pollen tablets for seasonal allergic rhinitis

Allergic rhinitis has a very high burden regarding both direct and indirect costs. This makes essential in the management of AR to reduce the clinical severity of the disease and thus to lessen its costs. This particularly concerns allergen immunotherapy (AIT), that, based on its immunological action on the causes of allergy, extends its benefit also after discontinuation of the treatment. From the pharmacoeconomic point of view, any treatment must be evaluated according to its cost-effectiveness, that is, the ratio between the cost of the intervention and its effect. A favorable cost-benefit ratio for AIT was defined, starting from the first studies in the 1990s on subcutaneous immunotherapy (SCIT) in AR patients, that highlighted a clear advantage on costs over the treatment with symptomatic drugs. Such outcome was confirmed also for sublingual immunotherapy (SLIT), that has also the advantage on SCIT to be free of the cost of the injections. Here we review the available literature on pharmacoeconomic data for SLIT with the 5-grass pollen tablets.

Suggestive association between variants in IL1RAPL and asthma symptoms in Latin American children

Several genome-wide association studies have been conducted to investigate the influence of genetic polymorphisms in the development of allergic diseases, but few of them have included the X chromosome. The aim of present study was to perform an X chromosome-wide association study (X-WAS) for asthma symptoms. The study included 1307 children of which 294 were asthma cases. DNA was genotyped using 2.5 HumanOmni Beadchip from Illumina. Statistical analyses were performed in PLINK 1.9, MACH 1.0 and Minimac2. The variant rs12007907 (g.29483892C>A) in IL1RAPL gene was suggestively associated with asthma symptoms in discovery set (odds ratio (OR)=0.49, 95% confidence interval (CI): 0.37-0.67; P=3.33 × 10^-6). This result was replicated in the ProAr cohort in men only (OR=0.45, 95% CI: 0.21-0.95; P=0.038). Furthermore, investigating the functional role of the rs12007907 on the production a Th2-type cytokine, IL-13, we found a negative association between the minor allele A with IL-13 production in the discovery set (P=0.044). Gene-based analysis revealed that NUDT10 was the most consistently associated with asthma symptoms in discovery sample. In conclusion, the rs12007907 variant in IL1RAPL gene was negatively associated with asthma and IL-13 production in our study and a sex-specific association was observed in one of the validation samples. It suggests an effect on asthma susceptibility and may explain differences in severe asthma frequency between women and men.

Addressing the misdiagnosis of asthma in adults: where does it go wrong?

INTRODUCTION

Asthma is diagnosed based on patients' respiratory symptoms of wheeze, cough, chest tightness and/or dyspnea together with physiologic evidence of variable and reversible expiratory airflow limitation. A high prevalence of overdiagnosis, underdiagnosis and misdiagnosis of adult asthma has been reported in the literature. Areas covered: Misdiagnosis of asthma in adults can occur in the community due to physicians' failure to confirm airflow limitation using spirometry, the relatively poor sensitivity of spirometry to absolutely rule in asthma, the complexity of multiple asthma phenotypes and endotypes, and the inherent day to day variability of asthma symptoms and airflow limitation. Consequences of asthma misdiagnosis to the patient and to the healthcare system include increased medication costs, increased potential side effects related to unnecessary use of medications and lost opportunities to diagnose the true cause of patients' respiratory symptoms. Expert commentary: Here we provide a review of the problem of misdiagnosis of adult asthma and suggestions for how to decrease the risk of misdiagnosis.

Prevalence of asthma among Middle Eastern children: A systematic review

Background: The prevalence of asthma and allergy has increased during the last decades, especially in children. However, little is known about it in the Middle East region. This systematic review is aimed to estimate the prevalence of asthma among the Middle Eastern children.

Methods: Local and international scientific databases including SID, Iranmedex, Medline and Science Direct were systematically searched for relevant keywords including; asthma, prevalence, children, International Study of Asthma and Allergies in Childhood (ISACC) and the names of Middle Eastern countries for the period of 1996-2011. Papers in Persian and English which met the defined criteria were included into the study. Bibliographies of the extracted articles were also searched. After extraction of data, heterogeneity between studies and publication bias were measured using Egger's-test. Effect size was pooled by the random-effect model. Since significant heterogeneity was found between studies, univariate meta-regression analyses were done to assess the association of variables with the overall results.

Results: Fifty studies in the Middle East examined the prevalence of asthma and allergy in children under the age of 18 years according to the ISAAC criteria and were included. A total number of 289,717 children were examined in the included studies and the prevalence varied from 0.7 % in Isfahan to 22.3 % in Bagdad. The total prevalence of diagnosed asthma was calculated 7.53 % (95% Cl: 6.38-8.75). Prevalence of asthma in the 13-14 years age group was 7.57% (95% Cl: 5.78-9.29) and in 6-7 years age group was 7.43% (95% Cl: 5.75-9.10). The prevalence of asthma among girls, based on random effect model, was 6.30% (95% Cl: 4.97-7.61) and among boys, it was 8.91% (95% Cl: 6.80-11.04).

Conclusion: The prevalence of asthma in the Middle East is lower than most developed countries. However, there is not enough longitudinal data to estimate the trend over time. In order to have more accurate estimates and to provide evidence for proper planning, standard epidemiologic studies should be conducted in countries of the region.

Different risk factor patterns for adult asthma, rhinitis and eczema: results from West Sweden Asthma Study

BACKGROUND

Atopic diseases including asthma, rhinitis and eczema have increased in the second half of the past century. This has been well studied among children and adolescents but with the exception of asthma to a much lesser extent in adults. The adult risk factor pattern of atopic diseases, in particular of eczema, and their relation to allergic sensitization are yet to be fully elucidated. Studies among adults that have compared the risk factor pattern for these conditions in the same material are very few. The objective of this study was to compare the risk factor patterns for asthma, rhinitis and eczema in a randomly selected adult population.

METHODS

A questionnaire survey on atopic diseases was dispatched by mail to 30,000 randomly selected individuals in West Sweden aged 16-75 years and 62 % participated. A subgroup of 2000 individuals was selected for clinical examinations including blood sampling for specific serum Immunoglobulin E to common airborne allergens and 1172 attended.

RESULTS

The prevalence of current asthma was 11.8 %, current rhinitis 42.8 %, current eczema 13.5 and 2.3 % had all three conditions while 13.9 % had at least two conditions. No mutual risk factor was identified for all three conditions. Allergic sensitization was a strong risk factor for current asthma (OR 4.1 CI 2.7-6.3) and current rhinitis (OR 5.1 CI 3.8-6.9) but not so for current eczema. Obesity was a risk factor for current asthma and current rhinitis, while farm childhood decreased the risk for current asthma and current rhinitis. Occupational exposure to gas dust or fumes and female sex was associated with an increased risk of current asthma and current eczema.

CONCLUSIONS

There are different risk factor patterns for asthma, rhinitis and eczema in adults but some risk factors are overlapping between some of the conditions. The effect of mutable risk factors should be assessed further in longitudinal studies.

[Skin sensitisation profiles to inhalant allergens for patients in Tétouan city (North West of Morocco)]

The prevalence of respiratory allergies is increasing and is a serious global health problem. The objective of the study was to determine the prevalence of skin sensitization to inhalant allergens in patients consulting for respiratory allergy, to identify the main allergens involved and to evaluate the profile of skin prick-test reactivity related to sex, age and season. This retrospective study included 379 patients consulting during 2009-2012 in three private medical offices of Tetouan. Of the 379 patients, 39.6% were monosensitized and 60.4% polysensitized. The percentages of polysensitized patients were higher in patients exhibiting rhinoconjunctivitis and astma-rhinoconjunctivitis than in subjects with asthma. The prevalence of symptoms according to sex showed no significant difference (P=0.64). Regarding age, a significant difference was observed in the case of rhinoconjunctivitis (P<0.01), while asthma and asthma-rhinoconjunctivitis showed no significant difference. Sensitization to house dust mites was the most frequent followed by grasses, olives and Parietaria. The multiple correspondence analyses (ACM) showed that patients under 20-years of age with asthma and asthma-rhinoconjunctivitis profile are more associated with sensitization to mites during the spring and autumn. The 20-49-year age group was represented mainly by polysensitized patients with rhinoconjunctivitis. Sensitization to mites ranks first in Tetouan followed by the percentage of sensitized patients to grass pollen and olive. The ACM showed that the house dust mite asthma seems to affect more children and adolescents while the 20-49 year age of polysensitized group suffers significantly rhinoconjunctivitis.

Prediction of Cardiovascular Disease Risk by Cardiac Biomarkers in 2 United Kingdom Cohort Studies: Does Utility Depend on Risk Thresholds For Treatment?

We tested the predictive ability of cardiac biomarkers N-terminal pro B-type natriuretic peptide (NT-proBNP), high-sensitivity troponin T, and midregional pro adrenomedullin for cardiovascular disease (CVD) events using the British Regional Heart Study (BRHS) of men aged 60 to 79 years, and the MIDSPAN Family Study (MFS) of men and women aged 30 to 59 years. They included 3757 and 2226 participants, respectively, and during median 13.0 and 17.3 years follow-up the primary CVD event rates were 16.6 and 5.3 per 1000 patient-years, respectively. In Cox models adjusted for basic classical risk factors, 1 SD increases in log-transformed NT-proBNP, high-sensitivity troponin T, and midregional pro adrenomedullin were generally associated with increased primary CVD risk in both the studies (P<0.006) except midregional pro adrenomedullin in MFS (P=0.10). In BRHS, QRISK2 risk factors yielded a C-index of 0.657, which was improved by 0.017 (P=0.005) by NT-proBNP, but not by other biomarkers. Using 28% 14-year risk as a proxy for 20% 10-year risk, NT-proBNP improved risk classification for primary CVD cases (case net reclassification index, 5.9%; 95% confidence interval, 2.8%-9.2%), but only improved classification of noncases at a 14% 14-year risk threshold (4.6%; 2.9%-6.3%). In MFS, ASSIGN risk factors yielded a C-index of 0.752 for primary CVD; none of the cardiac biomarkers improved the C-index. Improvements in risk classification were only seen using NT-proBNP and high-sensitivity troponin T among cases using the 28% 14-year risk threshold (4.7%; 1.0%-9.2% and 2.6%; 0.0%-5.8%, respectively). In conclusion, the improvement in treatment allocation gained by adding cardiac biomarkers to risk scores seems to depend on the risk threshold chosen for commencing preventative treatments.

Trends and socioeconomic disparities in preadolescent's health in the UK: evidence from two birth cohorts 32 years apart

BACKGROUND

Compared to children and adults, little is known about changes in adolescent health over time. This study profiles the health of preadolescents in two distinct time periods, 1980 and 2012.

METHODS

Secondary analysis of the British Cohort Study and the Millennium Cohort Study for preadolescents mostly aged between 10 and 11.5 years (range 9.75-13 years). The prevalence/average of, and socioeconomic gradients in, the following were compared between 1980 and 2012; general health problems, anthropometrics, allergic conditions, infectious diseases, health service use, smoking and parental smoking behaviour and maternal adiposity. Socioeconomic status was measured by familial income (3 groups).

RESULTS

There were decreases in the proportion of hospital admissions (Δ=-0.10(-0.09:-0.11)) smoking (Δ=-0.12(-0.11:-0.13)), parental smoking (mother: (Δ=-0.19(-0.18:-0.21)) father: (Δ=-0.35(-0.34:-0.37), infectious diseases (measles: (Δ=-0.46(-0.45:-0.47)) whooping cough: (Δ=-0.07(-0.06:-0.07)) and hearing problems (Δ=-0.04(-0.03:-0.05)). There were no changes in limiting long-standing illness (Δ=0.00 (-0.00:0.00)), or the proportion of children having two or more accidents requiring medical attention (Δ=-0.02(-0.00:-0.02)). There were increases in the proportion overweight (Δ=0.18(0.17:0.19)), maternal overweight(Δ=0.22(0.21:0.23)) and obesity(Δ=0.12(0.11:0.13)), height for age(Δ=0.47(0.44:0.49)), weight for age (Δ=0.68(0.65:0.71)), proportion reporting chicken pox (Δ=0.28(0.27:0.29)), allergic conditions (eczema Δ=0.19(0.18:0.20)), asthma Δ=0.12(0.11:0.13), hay fever Δ=0.15(0.14:0.16)) and wearing glasses (Δ=0.08(0.07:0.09)). There were increases in socioeconomic gradients for limiting long-standing illness, smoking, overweight, weight for age, height for age, wearing glasses, asthma and the onset of puberty.

CONCLUSIONS

There have been reductions in infectious diseases and tobacco exposure among British preadolescents, but overweight and allergic conditions have risen dramatically. Children from deprived families have benefitted least from improvements in health status, and have experienced the largest increases in health risks.

Maternal dietary antigen avoidance during pregnancy or lactation, or both, for preventing or treating atopic disease in the child

BACKGROUND

Some breastfed infants with atopic eczema benefit from elimination of cow milk, egg, or other antigens from their mother's diet. Maternal dietary antigens are also known to cross the placenta.

OBJECTIVES

To assess the effects of prescribing an antigen avoidance diet during pregnancy or lactation, or both, on maternal and infant nutrition and on the prevention or treatment of atopic disease in the child.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (6 July 2012).

SELECTION CRITERIA

All randomized or quasi-randomized comparisons of maternal dietary antigen avoidance prescribed to pregnant or lactating women. We excluded trials of multimodal interventions that included manipulation of the infant's diet other than breast milk or of non-dietary aspects of the infant's environment.

DATA COLLECTION AND ANALYSIS

We extracted data from published reports, supplemented by additional information received from the trialists we contacted.

MAIN RESULTS

The evidence from five trials, involving 952 participants, does not suggest a protective effect of maternal dietary antigen avoidance during pregnancy on the incidence of atopic eczema during the first 18 months of life. Data on allergic rhinitis or conjunctivitis, or both, and urticaria are limited to a single trial each and are insufficient to draw meaningful inferences. Longer-term atopic outcomes have not been reported. The restricted diet during pregnancy was associated with a slightly but statistically significantly lower mean gestational weight gain, a non-significantly higher risk of preterm birth, and a non-significant reduction in mean birthweight. The evidence from two trials, involving 523 participants, did not observe a significant protective effect of maternal antigen avoidance during lactation on the incidence of atopic eczema during the first 18 months or on positive skin-prick tests to cow milk, egg, or peanut antigen at one, two, or seven years. One crossover trial involving 17 lactating mothers of infants with established atopic eczema found that maternal dietary antigen avoidance was associated with a non-significant reduction in eczema severity.

AUTHORS' CONCLUSIONS

Prescription of an antigen avoidance diet to a high-risk woman during pregnancy is unlikely to reduce substantially her child's risk of atopic diseases, and such a diet may adversely affect maternal or fetal nutrition, or both. Prescription of an antigen avoidance diet to a high-risk woman during lactation may reduce her child's risk of developing atopic eczema, but better trials are needed. Dietary antigen avoidance by lactating mothers of infants with atopic eczema may reduce the severity of the eczema, but larger trials are needed.

Comparing the impact of personal and parental risk factors, and parental lifespan on all-cause mortality and cardiovascular disease: findings from the Midspan Family cohort study

BACKGROUND

We aimed to identify which personal and parental factors best explained all-cause mortality and cardiovascular disease (CVD).

METHODS

In 1996, data were collected on 2338 adult offspring of the participants in the 1972-1976 Renfrew and Paisley prospective cohort study. Recorded risk factors were assigned to 5 groups: mid-life biological and behavioural (BB), mid-life socioeconomic, parental BB, early-life socioeconomic and parental lifespan. Participants were followed up for mortality and hospital admissions to the end of 2011. Cox proportional hazards models were used to analyse how well each group explained all-cause mortality or CVD. Akaike's Information Criterion (AIC), a measure of goodness-of-fit, identified the most important groups.

RESULTS

For all-cause mortality (1997 participants with complete data, 111 deaths), decreases in AIC from the null model (adjusting for age and sex) to models including mid-life BB, mid-life socioeconomic, parental BB, early-life socioeconomic and parental lifespan were 55.8, 21.6, 10.3, 7.3 and 5.9, respectively. For the CVD models (1736 participants, 276 with CVD), decreases were 37.8, 3.7, 6.7, 17.3 and 0.4. Mid-life BB factors were the most important for both all-cause mortality and CVD; mid-life socioeconomic factors were important for all-cause mortality, and early-life socioeconomic factors were important for CVD. Parental lifespan was the weakest factor.

CONCLUSIONS

As mid-life BB risk factors best explained all-cause mortality and CVD, continued action to reduce these is warranted. Targeting adverse socioeconomic factors in mid-life and early life may contribute to reducing all-cause mortality and CVD risk, respectively.

The association between asthma and rhinitis is stable over time despite diverging trends in prevalence

BACKGROUND

Despite the well-known association between asthma and rhinitis, in Swedish adults the prevalence of rhinitis rose from 22% to 31% between 1990 and 2008 while asthma prevalence was unchanged. We tested whether the association of rhinitis with asthma was stable over time using the same population-based databases.

METHODS

Two surveys of adults (20-44 years) living in three regions of Sweden, carried out in 1990 (n = 8982) and 2008 (n = 9156) were compared. Identical questions regarding respiratory symptoms, asthma and rhinitis were used. Asthmatic wheeze: Wheeze with breathlessness apart from colds. Current asthma: Asthma attacks and/or asthma medication use.

RESULTS

Subjects with rhinitis had level time trends in asthmatic wheeze, current asthma and most nocturnal respiratory symptoms between 1990 and 2008, adjusted for age, sex, area and smoking. Any wheeze however decreased slightly. In never-smokers asthma symptoms were similarly associated with rhinitis in 1990 and 2008: any wheeze OR 4.0 vs. 4.4 (p = 0.339); asthmatic wheeze OR 6.0 vs. 5.9 (p = 0.937); and current asthma OR 9.6 vs. 7.7 (p = 0.213). In the whole population there were decreases in the asthma symptoms most closely associated to smoking, which decreased by half 1990-2008. Conversely current asthma, which was strongly associated with rhinitis and not with smoking, increased (p < 0.001).

CONCLUSIONS

The association of rhinitis with asthma was stable between 1990 and 2008. The pattern in the time trends of asthma outcomes strongly suggests that decreased smoking counterbalanced the driving effect of increased rhinitis on asthma prevalence. The findings illustrate the public health benefits of decreased smoking.

Operational definitions of asthma in recent epidemiological studies are inconsistent

OBJECTIVE

The best combination of questions to define asthma in epidemiological asthma studies is not known. We summarized the operational definitions of asthma used in prevalence studies and empirically assess how asthma prevalence estimates vary depending on the definition used.

METHODS

We searched the Thomson Reuters ISI Web of knowledge and included (1) cross-sectional studies (2) on asthma prevalence (3) conducted in the general population and (4) containing an explicit definition of asthma. The search was limited to the 100 most-cited papers or published since January 2010. For each paper, we recorded the asthma definition used and other variables. Then we applied the definitions to the data of the Portuguese National Asthma survey (INAsma) and of the 2005-2006 National Health and Nutrition Examination Survey (NHANES) computing asthma prevalence estimates for the different definitions.

RESULTS

Of 1738 papers retrieved, 117 were included for analysis. Lifetime asthma, diagnosed asthma and current asthma were defined in 8, 12 and 29 different ways, respectively. By applying definitions of current asthma on INAsma and NHANES data, the prevalence ranged between 5.3%-24.4% and 1.1%-17.2%, respectively.

CONCLUSIONS

There is considerable heterogeneity in the definitions of asthma used in epidemiological studies leading to highly variable estimates of asthma prevalence. Studies to inform a standardized operational definition are needed. Meanwhile, we propose a set of questions to be reported when defining asthma in epidemiological studies.

Prescription pattern of Chinese herbal products for adult-onset asthma in Taiwan: a population-based study

BACKGROUND

Throughout the world, asthma can be a life-threatening disease. Traditional Chinese medicine (TCM) is commonly used among Taiwanese adults to control many diseases.

OBJECTIVE

To analyze the use of Chinese herbal products (CHPs) among adults with asthma in Taiwan.

METHODS

The use, frequency of service, and the type of CHP prescribed for asthma among adults with asthma were evaluated. The study group consisted of a randomly sampled cohort of 1,000,000 beneficiaries from the National Health Insurance Research Database. Logistic regression was used to estimate the odds ratios (ORs) for use of CHP.

RESULTS

Overall, 20,627 asthma patients (85.7%) used TCM. Ding-chuan-tang (panting-stabilizing decoction) was the most frequently prescribed CHP, followed by xiao-qing-long-tang (minor green-blue dragon decoction) and ma-xing-gan-shi-tang (ephedra, apricot kernel, licorice, and gypsum decoction).

CONCLUSION

The use of CHPs among adults with asthma appears high. Ding-chuan-tang containing ma-huang is the most commonly prescribed and consumed among adults with asthma.

Active or passive exposure to tobacco smoking and allergic rhinitis, allergic dermatitis, and food allergy in adults and children: a systematic review and meta-analysis

BACKGROUND

Allergic rhinitis, allergic dermatitis, and food allergy are extremely common diseases, especially among children, and are frequently associated to each other and to asthma. Smoking is a potential risk factor for these conditions, but so far, results from individual studies have been conflicting. The objective of this study was to examine the evidence for an association between active smoking (AS) or passive exposure to secondhand smoke and allergic conditions.

METHODS AND FINDINGS

We retrieved studies published in any language up to June 30th, 2013 by systematically searching Medline, Embase, the five regional bibliographic databases of the World Health Organization, and ISI-Proceedings databases, by manually examining the references of the original articles and reviews retrieved, and by establishing personal contact with clinical researchers. We included cohort, case-control, and cross-sectional studies reporting odds ratio (OR) or relative risk (RR) estimates and confidence intervals of smoking and allergic conditions, first among the general population and then among children. We retrieved 97 studies on allergic rhinitis, 91 on allergic dermatitis, and eight on food allergy published in 139 different articles. When all studies were analyzed together (showing random effects model results and pooled ORs expressed as RR), allergic rhinitis was not associated with active smoking (pooled RR, 1.02 [95% CI 0.92-1.15]), but was associated with passive smoking (pooled RR 1.10 [95% CI 1.06-1.15]). Allergic dermatitis was associated with both active (pooled RR, 1.21 [95% CI 1.14-1.29]) and passive smoking (pooled RR, 1.07 [95% CI 1.03-1.12]). In children and adolescent, allergic rhinitis was associated with active (pooled RR, 1.40 (95% CI 1.24-1.59) and passive smoking (pooled RR, 1.09 [95% CI 1.04-1.14]). Allergic dermatitis was associated with active (pooled RR, 1.36 [95% CI 1.17-1.46]) and passive smoking (pooled RR, 1.06 [95% CI 1.01-1.11]). Food allergy was associated with SHS (1.43 [1.12-1.83]) when cohort studies only were examined, but not when all studies were combined. The findings are limited by the potential for confounding and bias given that most of the individual studies used a cross-sectional design. Furthermore, the studies showed a high degree of heterogeneity and the exposure and outcome measures were assessed by self-report, which may increase the potential for misclassification.

CONCLUSIONS

We observed very modest associations between smoking and some allergic diseases among adults. Among children and adolescents, both active and passive exposure to SHS were associated with a modest increased risk for allergic diseases, and passive smoking was associated with an increased risk for food allergy. Additional studies with detailed measurement of exposure and better case definition are needed to further explore the role of smoking in allergic diseases.

IgG-mediated down-regulation of IgE bound to mast cells: a potential novel mechanism of allergen-specific desensitization

BACKGROUND

Allergen-specific IgGs are known to inhibit IgE-mediated mast cell degranulation by two mechanisms, allergen-neutralization and engagement of the inhibitory FcγRIIB recruiting the phosphatase SHIP-1. Here we unravel an additional mechanism of IgG-mediated mast cell desensitization in mice: down-regulation of allergen-specific IgE.

METHODS

Mast cells were loaded in vitro and in vivo with monoclonal IgE antibodies specific for Fel d1 and exposed to immune complexes consisting of Fel d1-specific IgG antibodies recognizing different epitopes. Down regulation of IgE was followed by flow cytometry.

RESULTS

Mast cells loaded with 2 different IgE antibodies efficiently internalized the IgE antibodies if exposed to recombinant Feld d1. In contrast, no down-regulation occurred if mast cells were loaded with IgE antibodies exhibiting a single specificity before stimulation with recombinant Fel d1 [corrected]. Interestingly, however, IgEs of a single specificity were rapidly down-regulated in vitro and in vivo in the presence of Fel d1-specific monoclonal IgGs recognizing another epitope on Fel d1. Despite FceRI-internalization, little calcium flux or mast cell degranulation occurred. FcγRIIB played a dual role in the process since it enhanced IgE internalization and prevented cellular activation as documented by the inhibited calcium flux and mast cell degranulation. Similar observations were made in the presence of low concentrations of IgEs recognizing several epitopes on Fel d1.

CONCLUSION

We demonstrate here that Fel d1-specific IgG antibodies interact with FcγRIIB which (i) promotes IgE internalization; and (ii) inhibits mast cell activation. These results broaden our understanding of allergen-specific desensitization and may provide a mechanism for long-term desensitization of mast cells by selective removal of long-lived IgE antibodies on mast cells.

Prevalence trends in respiratory symptoms and asthma in relation to smoking - two cross-sectional studies ten years apart among adults in northern Sweden

Background

Smoking is considered to be the single most important preventable risk factor for respiratory symptoms. Estimating prevalence of respiratory symptoms is important since they most often precede a diagnosis of an obstructive airway disease, which places a major burden on the society. The aim of this study was to estimate prevalence trends of respiratory symptoms and asthma among Swedish adults, in relation to smoking habits. A further aim was to estimate the proportion of respiratory symptom and asthma prevalence attributable to smoking.

Methods

Data from two large-scale cross-sectional surveys among adults performed in northern Sweden in 1996 and 2006 were analysed. Identical methods and the same questionnaire were used in both surveys. The association between smoking, respiratory symptoms and asthma was analysed with multiple logistic regression analyses. Changes in prevalence of respiratory symptoms and asthma from 1996 to 2006 were expressed as odds ratios. Additionally, the population attributable risks of smoking were estimated.

Results

The prevalence of most respiratory symptoms decreased significantly from 1996 to 2006. Longstanding cough decreased from 12.4 to 10.1%, sputum production from 19.0 to 15.0%, chronic productive cough from 7.3 to 6.2%, and recurrent wheeze from 13.4 to 12.0%. Any wheeze and asthmatic wheeze remained unchanged. This parallels to a decrease in smoking from 27.4 to 19.1%. In contrast, physician-diagnosed asthma increased from 9.4 to 11.6%. The patterns were similar after correction for confounders. All respiratory symptoms were highly associated with smoking, and the proportion of respiratory symptoms in the population attributed to smoking (PAR) ranged from 9.8 to 25.5%. In 2006, PAR of smoking was highest for recurrent wheeze (20.6%).

Conclusions

In conclusion, we found that respiratory symptoms, in particular symptoms common in bronchitis, decreased among adults in northern Sweden, parallel to a decrease in smoking from 1996 to 2006. In contrast, the prevalence of physician-diagnosed asthma increased during the same time-period. Up to one fourth of the respiratory symptom prevalence in the population was attributable to smoking.

Asthma from the patient's perspective

BACKGROUND

Asthma is a chronic disease with considerable burden on health and economy. Despite growing knowledge about causes and treatment, many patients have uncontrolled asthma, activity and social limitations and reduced quality of life (QOL). Coping with asthma could be developed in a social and scientific context and influenced by personal experience.

OBJECTIVE

To investigate the asthmatic's perspective on asthma and how coping mechanisms with this disease were influenced by health professionals and networks.

METHODS

Asthma and QOL questionnaires were sent to 1191 individuals, who had participated in a population-based clinical study in 2004. Of the 7271 responders (72.7%), 10 chronic asthmatics (4 males and 6 females) with different asthma severity grades were recruited to in-depth interviews. The results were interpreted according to selected theories, especially Antonovsky's salutogenic theory on how comprehensibility, manageability and meaningfulness contribute to sense of coherence and successful coping with stressor/disease.

RESULTS AND CONCLUSION

Asthma comprehensibility was limited by both the lack of structured information about asthma diagnosis, treatment and prognosis and insufficient follow-up. The informants experimented with what worked and developed individual ways to accomplish satisfactory management. They adjusted their own medication and sometimes stopped prophylactic medicine as they did not detect an immediate effect. Many informants put their asthma into perspective, comparing it to what could have been worse. The unnoticeable development of asthma had probably triggered a gradual adaptation making it more complex for asthmatics to estimate severity. This together with their relative view of asthma might have led to gradual and uncritical accept of bothersome symptoms and reduced the need to seek professional advice or make important changes, e.g. eliminating exposure to irritating agents at work. Avoidance was a recurrent phenomenon as the asthmatics tended to drop physical activities with others instead of improving treatment. Several stated that they did not like to flash their asthma. They had concerns about being labelled as 'inadequate'. Physicians are urged to consider these tendencies and underlying the some of the mechanisms of 'living with asthma' in order to achieve proper asthma treatment and insure their patients' wellbeing.

Alternative ways of expressing forced expiratory volume in the first second and long-term mortality in elderly patients with asthma

BACKGROUND

Clinical and epidemiologic evidence on asthma in the elderly is scant. There is evidence that forced expiratory volume in the first second (FEV1), a commonly used indicator of overall pulmonary function, might not be an independent predictor of 5-year mortality in elderly patients with asthma.

OBJECTIVE

To investigate the association between FEV1 expressed using 3 alternative methods and 5-, 10-, and 15-year mortality in a population of elderly patients with asthma.

METHODS

Participants in the Salute Respiratoria nell' Anziano study were included. Asthma was diagnosed at baseline according to spirometric and clinical data. Vital status at 15 years was assessed using death registries. FEV1 was expressed as percentage of predicted, divided by height cubed, and as a multiple of the sex-specific first percentile. The association between FEV1 and mortality was evaluated using Cox proportional hazard models.

RESULTS

Two hundred patients were studied (52% women, mean age 73.1 years, standard deviation 6.2 years). All FEV1 measurements were associated with mortality at unadjusted analysis. After correction for potential confounders, no association was found between FEV1 and 5-year mortality. Only FEV1 as a multiple of the sex-specific first percentile was independently associated with 10-year (hazard ratio 0.35, 95% confidence interval 0.14-0.87) and 15-year (hazard ratio 0.38, 95% confidence interval 0.19-0.79) mortality.

CONCLUSION

Although extensively used, FEV1 expressed as percentage of predicted does not seem to be the best predictor of mortality in elderly patients with asthma. Although no spirometric index can predict 5-year mortality in this population, FEV1 as a multiple of the sex-specific first percentile should be considered when longer-term prognostic stratification is needed.

Cigarette smoking is associated with high prevalence of chronic rhinitis and low prevalence of allergic rhinitis in men

BACKGROUND

The harmful effects of tobacco smoke on human health, including respiratory health, are extensive and well documented. Previous data on the effect of smoking on rhinitis and allergic sensitization are inconsistent. We sought to investigate how smoking correlates with prevalence of allergic and chronic rhinitis among adults in Sweden.

METHODS

The study population comprised 27 879 subjects derived from three large randomly selected cross-sectional population surveys conducted in Sweden between 2006 and 2008. The same postal questionnaire on respiratory health was used in the three surveys, containing questions about obstructive respiratory diseases, rhinitis, respiratory symptoms and possible determinants of disease, including smoking habits. A random sample from one of the cohorts underwent a clinical examination including skin prick testing.

RESULTS

Smoking was associated with a high prevalence of chronic rhinitis in both men and women and a low prevalence of allergic rhinitis in men. These associations were dose dependent and remained when adjusted for a number of possible confounders in multiple logistic regression analysis. Prevalence of chronic rhinitis was lowest in nonsmokers and highest in very heavy smokers (18.5% vs 34.5%, P < 0.001). Prevalence of sensitization to common airborne allergens was lower in current smokers (25.9%, P = 0.008) and ex-smokers (28.2%, P = 0.022) than in nonsmokers (38.5%).

CONCLUSION

We found that smoking was associated with a high prevalence of chronic rhinitis in both sexes and a low prevalence of allergic rhinitis in men. The associations were dose dependent and remained when adjusting for several possible confounders.

[Indoor air quality and adult asthma]

INTRODUCTION

Asthma is a chronic inflammatory disease of the airways. The recent increase in its global prevalence suggests a possible role of environmental factors such as indoor air pollution. In 2000, according to the Institute Of Medicine, there was insufficient evidence to determine whether or not an association existed between high priority indoor air pollutants, listed by the French Indoor Air Quality Observatory, and asthma. The objective of this paper is to describe the current state of knowledge on the links between exposure to high priority indoor air pollutants and exacerbations of adult asthma.

METHOD

A review of the Medline database has been undertaken of the following pollutants: formaldehyde, benzene, acetaldehyde, volatile organic compounds, particles (PM2.5, PM10) and diethylhexyl-phthalate. The studies were classified by type and source of pollutant.

RESULTS

Twenty-three studies were included in the analysis. Most of the observational studies have shown an association between pollutants (by type and source) and adult asthma. The best documented pollutants were formaldehyde and volatile organic compounds. No studies were found on acetaldehyde and diethylhexyl-phthalate.

CONCLUSION

The analysis of the literature is complicated on account of the difficulty of comparing different studies. However, since the synthesis performed in 2000, the existence of a link between chemical indoor air pollutants and increased respiratory symptoms appears to be reinforced. It seems necessary to adopt preventive health measures while pursuing scientific research on this topic.

Circulating 25OHD, dietary vitamin D, PTH, and calcium associations with incident cardiovascular disease and mortality: the MIDSPAN Family Study

CONTEXT

Observational studies relating circulating 25-hydroxyvitamin D (25OHD) and dietary vitamin D intake to cardiovascular disease (CVD) have reported conflicting results.

OBJECTIVE

Our objective was to investigate the association of 25OHD, dietary vitamin D, PTH, and adjusted calcium with CVD and mortality in a Scottish cohort.

DESIGN AND SETTING

The MIDSPAN Family Study is a prospective study of 1040 men and 1298 women from the West of Scotland recruited in 1996 and followed up for a median 14.4 yr.

PARTICIPANTS

Locally resident adult offspring of a general population cohort were recruited from 1972-1976.

MAIN OUTCOME MEASURES

CVD events (n = 416) and all-cause mortality (n = 100) were evaluated.

RESULTS

25OHD was measured using liquid chromatography-tandem mass spectrometry in available plasma (n = 2081). Median plasma 25OHD was 18.6 ng/ml, and median vitamin D intake was 3.2 μg/d (128 IU/d). Vitamin D deficiency (25OHD <15 ng/ml) was present in 689 participants (33.1%). There was no evidence that dietary vitamin D intake, PTH, or adjusted calcium were associated with CVD events or with mortality. Vitamin D deficiency was not associated with CVD (fully adjusted hazard ratio = 1.00; 95% confidence interval = 0.77-1.31). Results were similar after excluding patients who reported an activity-limiting longstanding illness at baseline (18.8%) and those taking any vitamin supplements (21.7%). However, there was some evidence vitamin D deficiency was associated with all-cause mortality (fully adjusted hazard ratio = 2.02; 95% confidence interval = 1.17-3.51).

CONCLUSION

Vitamin D deficiency was not associated with risk of CVD in this cohort with very low 25OHD. Future trials of vitamin D supplementation in middle-aged cohorts should be powered to detect differences in mortality outcomes as well as CVD.

Factors influencing quality of life in asthmatics--a case-control study

INTRODUCTION

The quality of life (QOL) in persons with asthma is reduced and different factors such as demography, asthma severity and psychiatric comorbidity play an influential role. However, little is known about the interplay of these factors.

OBJECTIVE

To describe QOL in relation to asthma and analyse for the relative impact of asthma severity, psychiatric comorbidity, lifestyle (smoking and obesity) and demographic determinants on QOL in persons with asthma.

METHODS

One thousand one hundred sixty-one subjects from an earlier cohort with and without asthma were sent an asthma screening questionnaire and a generic QOL measuring instrument (15D).

RESULTS

Seven hundred seventy-eight valid responses (67%). QOL was significantly reduced in persons with asthma compared with controls (P = 0.001), almost on all domains of 15D. In the adjusted regression model, asthma severity, depression, female gender and smoking were associated with reduced QOL, suggesting that these factors play an independent role on lowering QOL. Depression did not inflate the relationship between asthma severity and worse QOL, suggesting that asthma severity plays an independent role on everyday life regardless of psychological state.

CONCLUSION

Asthma severity, psychiatric comorbidity, female gender and smoking were identified in this study to be major contributors to decreased QOL in asthmatics. Health professionals should be aware of this complex picture and take these factors into consideration when choosing the proper treatment of asthma patients. Asthma, asthma severity, epidemiology, psychiatric comorbidity, QOL.

Influence of asthma definition on the asthma-obesity relationship

Background

Epidemiological studies suggest an association between obesity and asthma in adults and children. Asthma diagnosis criteria are different among studies. The aim of this study was to test the influence of asthma definition on the asthma-obesity relationship.

Methods

In a cross-sectional analysis of 1922 men and women, subjects completed a translated questionnaire from the European Community Respiratory Health Survey and underwent spirometry and a bronchial challenge test. Weight, height and waist circumference were measured. Multiple logistic regression analysis was carried out to assess the association of variables related to obesity and asthma. Asthma was defined either by the presence of symptoms with bronchial hyperresponsiveness (BHR) or by a self-report of a physician-made diagnosis. The following variables were separately tested for associations with asthma: socioeconomic characteristics, schooling, physical activity, smoking status, anthropometry and spirometry.

Results

No association was detected between asthma confirmed by BHR and obesity indicators, odds ratio (OR) = 1.08 (95% confidence interval: 0.69 - 1.68) for obesity assessed by body mass index ≥ 30 kg/m²; OR = 1.02 (0.74 - 1.40) for obesity assessed by abnormal waist-to-height ratio; and, OR = 0.96 (0.69 - 1.33) for abnormal waist circumference. On the contrary, a previous diagnosis of asthma was associated with obesity, OR = 1.48 (1.01 - 2.16) for body mass index ≥ 30 kg/m²; OR = 1.48 (1.13 - 1.93) for abnormal waist-to-height ratio; and, OR = 1.32 (1.00 – 1.75) for abnormal waist circumference. Female gender, schooling ≥ 12 years and smoking were associated with BHR-confirmed asthma. Physically inactive subjects were associated with a previous diagnosis of asthma.

Conclusions

Our findings indicate that the relationship between asthma and obesity in epidemiological studies depends on the definition adopted. Certain components of asthma, for instance, symptoms may be more prone to the obesity influence than other ones, like bronchial hyperresponsiveness.

Maternal dietary antigen avoidance during pregnancy or lactation, or both, for preventing or treating atopic disease in the child

BACKGROUND

Some breastfed infants with atopic eczema benefit from elimination of cow milk, egg, or other antigens from their mother's diet. Maternal dietary antigens are also known to cross the placenta.

OBJECTIVES

To assess the effects of prescribing an antigen avoidance diet during pregnancy or lactation, or both, on maternal and infant nutrition and on the prevention or treatment of atopic disease in the child.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (6 July 2012).

SELECTION CRITERIA

All randomized or quasi-randomized comparisons of maternal dietary antigen avoidance prescribed to pregnant or lactating women. We excluded trials of multimodal interventions that included manipulation of the infant's diet other than breast milk or of non-dietary aspects of the infant's environment.

DATA COLLECTION AND ANALYSIS

We extracted data from published reports, supplemented by additional information received from the trialists we contacted.

MAIN RESULTS

The evidence from five trials, involving 952 participants, does not suggest a protective effect of maternal dietary antigen avoidance during pregnancy on the incidence of atopic eczema during the first 18 months of life. Data on allergic rhinitis or conjunctivitis, or both, and urticaria are limited to a single trial each and are insufficient to draw meaningful inferences. Longer-term atopic outcomes have not been reported. The restricted diet during pregnancy was associated with a slightly but statistically significantly lower mean gestational weight gain, a non-significantly higher risk of preterm birth, and a non-significant reduction in mean birthweight.The evidence from two trials, involving 523 participants, did not observe a significant protective effect of maternal antigen avoidance during lactation on the incidence of atopic eczema during the first 18 months or on positive skin-prick tests to cow milk, egg, or peanut antigen at one, two, or seven years.One crossover trial involving 17 lactating mothers of infants with established atopic eczema found that maternal dietary antigen avoidance was associated with a non-significant reduction in eczema severity.

AUTHORS' CONCLUSIONS

Prescription of an antigen avoidance diet to a high-risk woman during pregnancy is unlikely to reduce substantially her child's risk of atopic diseases, and such a diet may adversely affect maternal or fetal nutrition, or both. Prescription of an antigen avoidance diet to a high-risk woman during lactation may reduce her child's risk of developing atopic eczema, but better trials are needed.Dietary antigen avoidance by lactating mothers of infants with atopic eczema may reduce the severity of the eczema, but larger trials are needed.

Relationship between posttraumatic stress disorder and asthma among New York area residents exposed to the World Trade Center disaster

OBJECTIVE

The heightened prevalence rates of respiratory problems and posttraumatic stress disorder (PTSD) among New York area residents following the World Trade Center disaster on September 11, 2001, have received national attention. Although there is some evidence suggesting that PTSD is associated with increased risk for asthma, this relationship has not been well documented in this population at high risk for both disorders. There is also a need to examine this relationship while controlling for notable confounds, including dust exposure and smoking.

METHOD

This study examined the association between symptoms indicative of probable PTSD and the diagnosis of asthma following 9/11 among the individuals who participated in the World Trade Center Health Registry (WTCHR) baseline study between September 2003 and November 2004. A total of 71,437 participants enrolled in this study and completed questionnaires pertaining to exposure, physical health symptoms before and after 9/11, and self-reported PTSD symptoms.

RESULTS

Logistic regression revealed that, compared to participants without probable PTSD, individuals with probable PTSD were 1.65 times more likely to be diagnosed with asthma following 9/11, which was significant after controlling for the effects of gender, ethnicity, income, smoking status, dust exposure, and nonspecific psychological distress [Wald χ(2) (1)=52.375, P<.001].

CONCLUSION

These results suggest that PTSD symptoms are associated with the development of asthma following 9/11 and that this relationship is not explained by sociodemographic, environmental, and lifestyle factors.

Patient, practice and organisational influences on asthma control: observational data from a national study on primary care in the United Kingdom

BACKGROUND

Achieving asthma control is central to optimising patient quality of life and clinical outcome. Contemporary models of chronic disease management across a variety of countries point to the importance of micro, meso and macro level influences on patient care and outcome. However, asthma outcomes research has almost invariably concentrated on identifying and addressing patient predictors. Little is known about higher level organisational influences.

OBJECTIVE

This paper explores the contribution of organisational factors on poor asthma control, allowing for patient factors, at three organisational levels: the individual patient, local service deliverers, and strategic regional providers.

DESIGN, SETTING AND PARTICIPANTS

Prospective cross-sectional observational cohort study of 64,929 people with asthma from 1205 primary care practices spread throughout the United Kingdom (UK). Patient clinical data were recorded during a routine asthma review.

METHOD

Data were analysed using simple descriptive, multiple regression and complex multi-level modelling techniques, accounting for practice clustering of patients.

RESULTS

Poor asthma control was associated with areas of higher deprivation [regression coefficient 0.026 (95% confidence intervals 0.006; 0.046)] and urban practice [-0.155 (-0.275; -0.035)] but not all local and regional variation was explained by the data. In contrast, patient level predictors of poor control were: short acting bronchodilator overuse [2.129 (2.091; 2.164)], days-off due to asthma [1.203 (1.148; 1.258)], PEFR<80 [0.76 (0.666; 0.854)], non-use of a self-management plan (SMP) [0.554 (0.515; 0.593)], poor inhaler technique [0.53 (0.475; 0.585)], poor medication compliance [0.385 (-0.007; 0.777)], and gender [0.314 (0.281; 0.347)]. Pattern of medication use, smoking history, age, body mass index (BMI), and health service resource use were also significant factors for predicting control.

CONCLUSIONS

Targeting of health service resource requires knowledge of the factors associated with poor control of asthma symptoms. In the UK the contribution of local and regional structures appears minimal in explaining variation in asthma outcomes. However, unexplained variation in the data suggests other unrecorded factors may play a part. While patient personal characteristics (including self-management plan use, inhaler technique, medication compliance) appear to be the predominant influence the complex nature of the disease means that some, perhaps more subtle, influences are affecting the variability at all levels and this variance needs to be explored. Further research in other international contexts is required to identify the likely applicability of these findings to other health care systems.

Sex distribution of offspring-parents obesity: Angel's hypothesis revisited

This study, which is based on two cross sectional surveys' data, aims to establish any effect of parental obesity sex distribution of offspring and to replicate the results that led to the hypothesis that obesity may be associated with sex-linked recessive lethal gene. A representative sample of 4,064 couples living in Renfrew/Paisley, Scotland was surveyed 1972-1976. A total of 2,338 offspring from 1,477 of the couples screened in 1972-1976, living in Paisley, were surveyed in 1996. In this study, males represented 47.7% among the total offspring of the couples screened in 1972-1976. In the first survey there was a higher male proportion of offspring (53%, p < 0.05) from parents who were both obese, yet this was not significant after adjustment for age of parents. Also, there were no other significant differences in sex distribution of offspring according to body mass index, age, or social class of parents. The conditions of the original 1949 study of Angel ( 1949 ) (which proposed a sex-linked lethal recessive gene) were simulated by selecting couples with at least one obese daughter. In this subset, (n = 409), obesity in fathers and mothers was associated with 26% of offspring being male compared with 19% of offspring from a non-obese father and obese mother. Finally we conclude that families with an obese father have a higher proportion of male offspring. These results do not support the long-established hypotheses of a sex-linked recessive lethal gene in the etiology of obesity.

Intergenerational change and familial aggregation of body mass index

The relationship between parental BMI and that of their adult offspring, when increased adiposity can become a clinical issue, is unknown. We investigated the intergenerational change in body mass index (BMI) distribution, and examined the sex-specific relationship between parental and adult offspring BMI. Intergenerational change in the distribution of adjusted BMI in 1,443 complete families (both parents and at least one offspring) with 2,286 offspring (1,263 daughters and 1,023 sons) from the west of Scotland, UK, was investigated using quantile regression. Familial correlations were estimated from linear mixed effects regression models. The distribution of BMI showed little intergenerational change in the normal range (<25 kg/m(2)), decreasing overweightness (25-<30 kg/m(2)) and increasing obesity (≥30 kg/m(2)). Median BMI was static across generations in males and decreased in females by 0.4 (95% CI: 0.0, 0.7) kg/m(2); the 95th percentile increased by 2.2 (1.1, 3.2) kg/m(2) in males and 2.7 (1.4, 3.9) kg/m(2) in females. Mothers' BMI was more strongly associated with daughters' BMI than was fathers' (correlation coefficient (95% CI): mothers 0.31 (0.27, 0.36), fathers 0.19 (0.14, 0.25); P = 0.001). Mothers' and fathers' BMI were equally correlated with sons' BMI (correlation coefficient: mothers 0.28 (0.22, 0.33), fathers 0.27 (0.22, 0.33). The increase in BMI between generations was concentrated at the upper end of the distribution. This, alongside the strong parent-offspring correlation, suggests that the increase in BMI is disproportionally greater among offspring of heavier parents. Familial influences on BMI among middle-aged women appear significantly stronger from mothers than fathers.