Physical activity and amyloid-β plasma and brain levels: results from the Australian Imaging, Biomarkers and Lifestyle Study of Ageing

Previous studies suggest physical activity improves cognition and lowers Alzheimer's disease (AD) risk. However, key AD pathogenic factors that are thought to be influenced by physical activity, particularly plasma amyloid-β (Aβ) and Aβ brain load, have yet to be thoroughly investigated. The objective of this study was to determine if plasma Aβ and amyloid brain deposition are associated with physical activity levels, and whether these associations differed between carriers and non-carriers of the apolipoprotein E (APOE) ε4 allele. Five-hundred and forty six cognitively intact participants (aged 60-95 years) from the Australian Imaging, Biomarkers and Lifestyle Study of Ageing (AIBL) were included in these analyses. Habitual physical activity levels were measured using the International Physical Activity Questionnaire (IPAQ). Serum insulin, glucose, cholesterol and plasma Aβ levels were measured in fasting blood samples. A subgroup (n=116) underwent (11)C-Pittsburgh compound B (PiB) positron emission tomography (PET) scanning to quantify brain amyloid load. Higher levels of physical activity were associated with higher high density lipoprotein (HDL) (P=0.037), and lower insulin (P<0.001), triglycerides (P=0.019) and Aβ1-42/1-40 ratio (P=0.001). After stratification of the cohort based on APOE ε4 allele carriage, it was evident that only non-carriers received the benefit of reduced plasma Aβ from physical activity. Conversely, lower levels of PiB SUVR (standardised uptake value ratio) were observed in higher exercising APOE ε4 carriers. Lower plasma Aβ1-42/1-40 and brain amyloid was observed in those reporting higher levels of physical activity, consistent with the hypothesis that physical activity may be involved in the modulation of pathogenic changes associated with AD.

Impaired innate interferon induction in severe therapy resistant atopic asthmatic children

Deficient type I interferon-β and type III interferon-λ induction by rhinoviruses has previously been reported in mild/moderate atopic asthmatic adults. No studies have yet investigated if this occurs in severe therapy resistant asthma (STRA). Here, we show that compared with non-allergic healthy control children, bronchial epithelial cells cultured ex vivo from severe therapy resistant atopic asthmatic children have profoundly impaired interferon-β and interferon-λ mRNA and protein in response to rhinovirus (RV) and polyIC stimulation. Severe treatment resistant asthmatics also exhibited increased virus load, which negatively correlated with interferon mRNA levels. Furthermore, uninfected cells from severe therapy resistant asthmatic children showed lower levels of Toll-like receptor-3 mRNA and reduced retinoic acid inducible gene and melanoma differentiation-associated gene 5 mRNA after RV stimulation. These data expand on the original work, suggesting that the innate anti-viral response to RVs is impaired in asthmatic tissues and demonstrate that this is a feature of STRA.

Prevalence of scoliosis in cystic fibrosis

BACKGROUND

The prevalence of idiopathic scoliosis in the general pediatric population is reported to be between 0.5% and 3.2%. Previous studies have reported an increased prevalence of scoliosis in children with cystic fibrosis (CF).

HYPOTHESIS

The prevalence of scoliosis in CF children is greater than in the normal population.

METHODS

Chest X-rays of 319 patients attending the Royal Brompton CF Centre were reviewed. The Cobb angle of any spinal lateral curvature was measured. Scoliosis was defined as a Cobb angle of more than 10°.

RESULTS

Median age of the whole group of patients was 10.9 years (range 1.1-18 years), 53% were females. Seven patients (2.2%) had radiological signs of scoliosis, their mean age was 14.5 ± 2.3 years (range: 11.5-18 years), 5 were females. Age at onset of scoliosis was between 5 and 10 years for three patients and over 10 years for the others. All the curves were thoracic and with right convexity: apices between T7 and T9 for the single curves (n = 5) and between T4 and T5 (n = 2) for the double curves.

CONCLUSION

CF patients showed a similar prevalence of scoliosis as in the normal population (2.2% vs. 0.5-3.2%). There was the same gender (female) and side (right-sided) predilection as in normal population.

Risk management protocol for gastrostomy and jejunostomy insertion in ventilator dependent infants

Gastrostomy, gastrojejunostomy and anti-reflux surgery in infants and children who are chronically ventilator dependent are associated with significant risk of morbidity and mortality. We report outcomes of 22 high risk children who underwent these procedures at our centre. Pre-operative investigations included: overnight oxygen and carbon dioxide monitoring and subsequent optimisation of ventilatory support, echocardiography, video fluoroscopy, and assessment of gastroesophageal reflux. We carried out 24 procedures under general anaesthesia. Twenty-one children used ventilatory support pre-operatively. Median age of first surgical procedure was 18 months (range 3-180). Supplementary feeding was commenced in 20 children prior to procedure, median age 9 months (1-31). Median PICU length of stay was 1 (1-8) days. No children died in the post-operative period. Extubation was possible within 24h in 87% of cases. Complications included; atelectasis (n=2), ileus (n=2), abdominal distension (n=4) and loose stools (n=1). We conclude that, in this high risk cohort of ventilator dependent children with predominantly neuromuscular disorders, with careful assessment, operative intervention can be carried out under general anaesthesia, with the child being extubated early back onto their routine ventilatory support and aggressive airway clearance. Additionally this protocol can minimise post-operative complications and is associated with a good outcome in the majority.

Blood eosinophil counts rarely reflect airway eosinophilia in children with severe asthma

BACKGROUND

The inflammatory phenotypes of severe asthma in adults may be reflected in peripheral blood. If this were true in children with severe therapy-resistant asthma (STRA), invasive tests could be avoided. At the moment there is no conclusive evidence in children.

METHODS

All patients underwent blood tests, exhaled nitric oxide (FeNO), sputum induction, bronchoalveolar lavage (BAL) and endobronchial biopsy (EB).

RESULTS

Sixty-three (71.6%) patients had a normal blood profile and only 1/88 had a combined blood eosinophilia and neutrophilia. 76/88 (86%) had normal blood eosinophils, but of these, 84% had airway eosinophilia in either BAL (n = 43;66%) or EB (n = 41;79%). In children with STRA blood eosinophilia was associated with airway eosinophilia. However, normal blood eosinophil levels did not exclude airway eosinophilic inflammation.

CONCLUSIONS

Peripheral blood counts are not reliable in characterising airway inflammation in severe asthmatic children exposed to high dose steroid therapy, therefore bronchoscopy with BAL should be considered.

The dark side of the moon: severe therapy-resistant asthma in children

Problematic severe asthma is the term used to describe children whose asthma is not responsive to standard therapy with high-dose inhaled corticosteroids and additional controllers. These children need to be assessed by a step-wise systematic protocol in order to confirm the diagnosis, evaluate co-morbidities, assess the adherence to treatment, and finally evaluate the basic management. More than half of these children have "difficult-to-treat asthma", which improves if the basic management is correct. Children whose asthma remains uncontrolled despite resolution of any reversible factors are termed "severe therapy-resistant" asthmatics; for them, an individualised treatment plan is developed after a detailed and invasive protocol of investigation. Therapeutic options for these patients can be divided into medications used in lower doses for children with less severe asthma, and those used in other pediatric diseases but not for asthma. Most treatments are unlicensed and there is a lack of high-quality evidence. Children with recurrent severe exacerbations, in particular in the context of good baseline asthma control, are particularly difficult to treat, and there is no evidence on which therapeutic option to recommend. International collaborations, using standard protocols of investigation, are needed to better understand mechanisms of severe therapy-resistant asthma and to deliver evidence-based treatments in the future.

Allergic Rhinitis and its Impact on Asthma (ARIA): achievements in 10 years and future needs

Allergic rhinitis (AR) and asthma represent global health problems for all age groups. Asthma and rhinitis frequently coexist in the same subjects. Allergic Rhinitis and its Impact on Asthma (ARIA) was initiated during a World Health Organization workshop in 1999 (published in 2001). ARIA has reclassified AR as mild/moderate-severe and intermittent/persistent. This classification closely reflects patients' needs and underlines the close relationship between rhinitis and asthma. Patients, clinicians, and other health care professionals are confronted with various treatment choices for the management of AR. This contributes to considerable variation in clinical practice, and worldwide, patients, clinicians, and other health care professionals are faced with uncertainty about the relative merits and downsides of the various treatment options. In its 2010 Revision, ARIA developed clinical practice guidelines for the management of AR and asthma comorbidities based on the Grading of Recommendation, Assessment, Development and Evaluation (GRADE) system. ARIA is disseminated and implemented in more than 50 countries of the world. Ten years after the publication of the ARIA World Health Organization workshop report, it is important to make a summary of its achievements and identify the still unmet clinical, research, and implementation needs to strengthen the 2011 European Union Priority on allergy and asthma in children.

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

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

Prevention and control of childhood asthma and allergy in the EU from the public health point of view: Polish Presidency of the European Union

The leading priority for the Polish Presidency of the Council of the European Union was to reduce health inequalities across European societies, and, within its framework, prevention and control of respiratory diseases in children. This very important paper contain proposal of international cooperation on the prevention, early detection and monitoring of asthma and allergic diseases in childhood which will be undertaken by the EU member countries as a result of EU conclusion developed during the Polish Presidency of the Council of the European Union. This will result in collaboration in the field of chronic diseases, particularly respiratory diseases, together with the activity of the network of national institutions and NGOs in this area. Paper also contains extensive analysis of the socio-economic, political, epidemiological, technological and medical factors affecting the prevention and control of childhood asthma and allergy presented during Experts presidential conference organized in Warsaw-Ossa 21–22 September 2011.

Genome-wide association study to identify genetic determinants of severe asthma

BACKGROUND

The genetic basis for developing asthma has been extensively studied. However, association studies to date have mostly focused on mild to moderate disease and genetic risk factors for severe asthma remain unclear.

OBJECTIVE

To identify common genetic variants affecting susceptibility to severe asthma.

METHODS

A genome-wide association study was undertaken in 933 European ancestry individuals with severe asthma based on Global Initiative for Asthma (GINA) criteria 3 or above and 3346 clean controls. After standard quality control measures, the association of 480 889 genotyped single nucleotide polymorphisms (SNPs) was tested. To improve the resolution of the association signals identified, non-genotyped SNPs were imputed in these regions using a dense reference panel of SNP genotypes from the 1000 Genomes Project. Then replication of SNPs of interest was undertaken in a further 231 cases and 1345 controls and a meta-analysis was performed to combine the results across studies.

RESULTS

An association was confirmed in subjects with severe asthma of loci previously identified for association with mild to moderate asthma. The strongest evidence was seen for the ORMDL3/GSDMB locus on chromosome 17q12-21 (rs4794820, p=1.03×10((-8)) following meta-analysis) meeting genome-wide significance. Strong evidence was also found for the IL1RL1/IL18R1 locus on 2q12 (rs9807989, p=5.59×10((-8)) following meta-analysis) just below this threshold. No novel loci for susceptibility to severe asthma met strict criteria for genome-wide significance.

CONCLUSIONS

The largest genome-wide association study of severe asthma to date was carried out and strong evidence found for the association of two previously identified asthma susceptibility loci in patients with severe disease. A number of novel regions with suggestive evidence were also identified warranting further study.

Congenital diaphragmatic hernia

Infants with congenital diaphragmatic hernia (CDH) have significant mortality and long-term morbidity. Only 60-70% survive and usually those in high-volume centres. The current Task Force, therefore, has convened experts to evaluate the current literature and make recommendations on both the antenatal and post-natal management of CDH. The incidence of CDH varies from 1.7 to 5.7 per 10,000 live-born infants depending on the study population. Antenatal ultrasound scanning is routine and increasingly complemented by the use of magnetic resonance imaging. For isolated CDH, antenatal interventions should be considered, but the techniques need vigorous evaluation. After birth, management protocols are often used and have improved outcome in nonrandomised studies, but immediate intubation at birth and gentle ventilation are important. Pulmonary hypertension is common and its optimal management is crucial as its severity predicts the outcome. Usually, surgery is delayed to allow optimal medical stabilisation. The role of minimal invasive post-natal surgery remains to be further defined. There are differences in opinion about whether extracorporeal membrane oxygenation improves outcome. Survivors of CDH can have a high incidence of comorbidities; thus, multidisciplinary follow-up is recommended. Multicentre international trials are necessary to optimise the antenatal and post-natal management of CDH patients.

I have taken my umbrella, so of course it does not rain

Spirometry is used worldwide to diagnose respiratory disease, and it is a validated measure to assess airway obstruction. Irreversible airway obstruction is the defining feature of chronic obstructive pulmonary disease (COPD). Thus, an FEV(1)/FVC ratio <70% is used to diagnose COPD, and the severity is thereafter based on the level of FEV(1). This definition is widely used in clinical practice and research, yet may lead to confusion with respect to the diagnosis associated with the presence of airway obstruction. The three main reasons are the following: (1) fixed airflow obstruction may be the result of specific diagnoses such as cystic fibrosis; (2) FEV(1)/FVC ratio changes with ageing, and it is therefore inappropriate to use the same ratio at 40 and 90 years, leaving aside gender differences; (3) even when specific diagnoses are excluded, fixed airflow obstruction may be the end-stage of many different underlying processes. The authors believe that they have strong arguments that a COPD diagnosis based solely on spirometric values is nonsense. More sophisticated lung function tests, such as plethysmography, forced oscillation and lung clearance index, may help further to delineate the characteristics of low lung function. However, these are not feasible in most clinical contexts and in epidemiologic studies. Therefore, the authors throw down the gauntlet: spirometry is an essential tool in patient evaluation but dangerous for disease diagnosis, and the term COPD should only be used in the appropriate clinical (diagnostic) context.

Relationship between past airway pathology and current lung function in preschool wheezers

The functional outcome in preschool severe wheezers with eosinophilic airway inflammation and increased reticular basement membrane (RBM) thickness is unknown. We investigated the relationship between airway pathology at age 2 yrs and lung function at age 4-6 yrs in previous severe wheezers. Severe wheezers previously investigated by endobronchial biopsy and healthy children aged 4-6 yrs were recruited. Lung clearance index (LCI), conducting zone ventilation inhomogeneity (S(cond)), acinar ventilation inhomogeneity by multiple-breath washout, plethysmographic-specific airway resistance and exhaled nitric oxide fraction (F(eNO)) were measured. Lung function was compared between wheezers and healthy controls, and in wheezers correlated with past RBM thickness and mucosal eosinophilia (EG2+ cells). 72 healthy controls and 28 previous severe wheezers were tested. Wheezers had significantly higher median LCI (6.8 versus 6.6; p=0.001) and S(cond) (0.046 versus 0.016; p<0.0005) than healthy controls. Past RBM thickness (r=0.474, p=0.047) and EG2+ cells (r=0.552, p=0.041) showed significant correlations with current F(eNO), but no correlations were seen between past RBM thickness and current lung function. RBM thickness and EG2+ cells at age 2 yrs show a significant positive association with F(eNO) at age 5 yrs. Although lung function was abnormal at age 5 yrs in severe wheezers, this did not correlate with past RBM thickness.

Pharmacological treatment of severe, therapy-resistant asthma in children: what can we learn from where?

There is a lack of high-quality evidence on what treatment should be used in children with properly characterised severe, therapy-resistant asthma. Data have to be largely extrapolated from trials in children with mild asthma, and adults with severe asthma. Therapeutic options can be divided into medications used in lower doses for children with less severe asthma, and those used in other paediatric diseases but not for asthma (for example, methotrexate). In the first category are high-dose inhaled corticosteroids (ICS) (≤ 2,000 μg · day(-1) fluticasone equivalent), oral prednisolone, the anti-immunoglobulin (Ig)E antibody omalizumab, high-dose long-acting β(2)-agonists, low-dose oral theophylline and intramuscular triamcinolone. If peripheral airway inflammation is thought to be a problem, the use of fine-particle ICS or low-dose oral corticosteroids may be considered. More experimental therapies include oral macrolides, cyclosporin, cytotoxic drugs such as methotrexate and azathioprine, gold salts, intravenous infusions of Ig, subcutaneous β(2)-agonist treatment and, in those sensitised to fungi, oral antifungal therapy with itraconazole or voriconazole. Those with recurrent severe exacerbations, particularly in the context of good baseline asthma control, are particularly difficult to treat; baseline control and lung function must be optimised with the lowest possible dose of ICS, and allergen triggers and exposures minimised. The use of high-dose ICS, leukotriene receptor antagonists or both at the time of exacerbations can be considered. There is no evidence regarding which therapeutic option to recommend. Better evidence is required for all these treatment options, underscoring the need for the international and co-ordinated approach which we have previously advocated.