Chronic Respiratory Disease In Children Research Articles

Analysis of impulse oscillometric measures of lung function and respiratory system model parameters in small airway-impaired and healthy children over a 2-year period.

BackgroundIs Impulse Oscillometry System (IOS) a valuable tool to measure respiratory system function in Children?Asthma (A) is the most prevalent chronic respiratory disease in children. Therefore, early and accurate assessment of respiratory function is of tremendous clinical interest in diagnosis, monitoring and treatment of respiratory conditions in this subpopulation.IOS has been successfully used to measure lung function in children with a high degree of sensitivity and specificity to small airway impairments (SAI) and asthma. IOS measures of airway function and equivalent electrical circuit models of the human respiratory system have been developed to quantify the severity of these conditions. Previously, we have evaluated several known respiratory models based on the Mead's model and more parsimonious versions based on fitting IOS data known as extended RIC (eRIC) and augmented RIC (aRIC) models have emerged, which offer advantages over earlier models.MethodsIOS data from twenty-six children were collected and compared during pre-bronchodilation (pre-B) and post- bronchodilation (post-B) conditions over a period of 2 years.Results and DiscussionAre the IOS and model parameters capable of differentiating between healthy children and children with respiratory system distress?Children were classified into two main categories: Healthy (H) and Small Airway-Impaired (SAI). The IOS measures and respiratory model parameters analyzed differed consistently between H and SAI children. SAI children showed smaller trend of "growth" and larger trend of bronchodilator responses than H children.The two model parameters: peripheral compliance (Cp) and peripheral resistance (Rp) tracked IOS indices of small airway function well. Cp was a more sensitive index than Rp. Both eRIC and aRIC Cps and the IOS Reactance Area, AX, (also known as the "Goldman Triangle") showed good correlations.ConclusionsWhat are the most useful IOS and model parameters?In this work we demonstrate that IOS parameters such as resistance at 5 Hz (R5), frequency-dependence of resistance (fdR: R5-R20), reactance area (AX), and parameter estimates of respiratory system such as Cp and Rp provide sensitive indicators of lung function and have the capacity to differentiate between obstructed and non-obstructed airway conditions. They are also capable of demonstrating airway growth-related changes over a two-year period.We conclude that the IOS parameters AX and the eRIC model derived parameter Cp are the most reliable parameters to track lung function in children before and after bronchodilator and over a time period (2 years).Which model is more suitable for interpreting IOS data?IOS data are equally well-modelled by eRIC and aRIC models, based on the close correlations of their corresponding parameters - excluding upper airway shunt compliance. The eRIC model is a more parsimonious and equally powerful model in capturing the differences in IOS indices between SAI and H children. Therefore, it may be considered a clinically-preferred model of lung function.

Virus memory induces airway hyperreactivity through eosinophil activation

Objective/purpose Asthma is the most common chronic respiratory disease in children. Asthma exacerbation occurs when the airways acutely become obstructed, usually the result of airway inflammation. The Inflammation is caused by a unique mix of cells, and includes eosinophils. The majority of asthma exacerbations occur after a viral infection such as a common cold. Why asthmatic children develop such severe reactions to viruses is unclear. Our previous work suggests asthmatic patients develop severe airway obstruction because they have too many eosinophils in their airways before virus infection. The virus triggers these eosinophils to release harmful mediators and cause airway damage. We believe that in humans, it may be the mere presence of virus antigen that stimulates memory cells to activate the eosinophils. We hypothesize that memory T cell proliferation and eosinophil activation will occur in response to any airway virus for which immune memory exists, and that removal of the eosinophils will prevent airway hyperreactivity (AHR). In addition, we believe that this model is representative of virus-induced asthma exacerbation. As part of our project to develop non-invasive diagnostics using the metabolomic profile of urine through Nuclear Magnetic Resonance (NMR) spectroscopy, we are saving the urine samples from these animals. We hypothesize that there will be relevant differences between the urine profiles of each animal group, which will be applicable to humans.

Assessment of geographical patterns of chronic respiratory diseases in children of Koper municipality

Geografski Vzorci Pojavljanja Bolezni Dihalnih Poti Otrok V Občini Koper Izhodišče: Kronične bolezni dihal so naraščajoč zdravstveni problem, s katerim se srečujemo v razvitih okoljih, torej tudi v Sloveniji. Pri tem se bolezni, kot so astma, kronični bronhitis ali različne alergijske bolezni, ki se kazKejo s prizadetostjo dihalnih poti, neredko pokazKejo zKe zelo zgodaj v otroštvu. Cilj študije je bil raziskati geografske vzorce bolezni dihal med učenci 1. do 4. razreda v mestni občini (MO) Koper, ki lezKi v jugozahodni Sloveniji. Metode: Podatke o razporeditvi obolelih smo dobili z obdelavo vprašalnikov raziskave «Proučevanje vpliva okolja na pojav določenih bolezni in povečano stopnjo umrljivosti prebivalcev na območju dela Mestne občine Koper» iz leta 2003. Za iskanje geografskih vzorcev pojavljanja primerov smo uporabili metode prostorske statistične analize, metodo glajenja, analizo kopičenja (globalne indekse prostorske avtokorelacije) in analizo gruč (lokalne indekse prostorske avtokorelacije). Rezultati: Globalni test Moran I je nakazal statistično značilno kopičenje primerov (Globalni Moran p=0.0211). Lokalni test prostorske avtokorelacije Moran I, prilagojen za variabilnost stopenj zbolevnosti, je pokazal statistično značilne rezultate (p <0,05) za območje krajevnih skupnosti (KS) "Sveti Anton" (lokalni Moran p = 0,0454), ki s statistično značilnostjo in pozitivno prostorsko avtokorelacijo opredeljuje jedro gruče, ki sega v okoliške KS "Marezige", "Dekani", "Pobegi-ČezKarji" in "Vanganel". Zaključki: Študija je vizualno prikazala in statistično potrdila prostorsko kopičenje z višjo stopnjo zbolevnosti dihalnih poti na območju MO Koper. Ugotovili smo, da je prostorska analiza primeren postopek, ker na tak način lazKje opredelimo in določimo geografske vzorce porazdelitve bolezni.

Traffic-related air pollution associated with prevalence of asthma and COPD/chronic bronchitis. A cross-sectional study in Southern Sweden

BackgroundThere is growing evidence that air pollution from traffic has adverse long-term effects on chronic respiratory disease in children, but there are few studies and more inconclusive results in adults. We examined associations between residential traffic and asthma and COPD in adults in southern Sweden. A postal questionnaire in 2000 (n = 9319, 18–77 years) provided disease status, and self-reported exposure to traffic. A Geographical Information System (GIS) was used to link geocoded residential addresses to a Swedish road database and an emission database for NOx.ResultsLiving within 100 m of a road with >10 cars/minute (compared with having no heavy road within this distance) was associated with prevalence of asthma diagnosis (OR = 1.40, 95% CI = 1.04–1.89), and COPD diagnosis (OR = 1.64, 95%CI = 1.11–2.4), as well as asthma and chronic bronchitis symptoms. Self-reported traffic exposure was associated with asthma diagnosis and COPD diagnosis, and with asthma symptoms. Annual average NOx was associated with COPD diagnosis and symptoms of asthma and chronic bronchitis.ConclusionLiving close to traffic was associated with prevalence of asthma diagnosis, COPD diagnosis, and symptoms of asthma and bronchitis. This indicates that traffic-related air pollution has both long-term and short-term effects on chronic respiratory disease in adults, even in a region with overall low levels of air pollution.

Respiratory-related evoked potentials in children with asthma

Aims of the study Respiratory-related evoked potentials (RREPs) are a method of recording brain activities in response to respiratory stimuli. Although data in childhood are scarce, the absence of the early P1 component of RREPs has been reported in children with a history of life-threatening asthma. This study was focused on the presence, latencies, and amplitudes of the P1, N1, P2, and N2 components of the RREPs in a paediatric series of asthmatic patients. Patients and methods RREPs were recorded in 21 patients with stable asthma, age range 8–17 years, 11 healthy children, age range 6–16 years, and 24 healthy adults, age range 20–28 years. The signals from left (C3–Cz) and right (C4–Cz) central (rolandic) location were recorded separately, using surface electrodes. Evoked responses to two series of 80 consecutive mid-inspiratory occlusions were averaged. Recordings were analysed manually. Results All 4 RREPs components were significantly more often absent in asthmatic children than in healthy children and adults (P1, p = 0.01; N1, p = 0.008; P2, p = 0.008, N2, p = 0.01). The latencies and amplitudes of the four components were similar in patients and healthy subjects. Conclusion RREPs components were less frequently present in children with asthma than in healthy subjects. This finding should promote the recording of RREPs in other acute and chronic respiratory diseases in children in order to search for possible electroclinical correlations.

The Importance of Multichannel Intraluminal Impedance in the Evaluation of Children with Persistent Respiratory Symptoms

Previous evidence suggests an association between gastroesophageal reflux disease and chronic respiratory disease in children. Despite antisecretory antacid therapy, respiratory symptoms often persist supporting a role for nonacid reflux. The aim of this study was to determine whether nonacid reflux occurs in children with chronic respiratory disease. Twenty-eight children (mean age: 6.5 +/- 5.6 yr) with persistent respiratory symptoms on antacid medications underwent 24 h pH/multichannel intraluminal impedance (pH/MII) recording. The symptom index (SI) and the symptom sensitivity index (SSI) were calculated for each patient. Logistic regression was performed to determine which reflux characteristics were associated with a high degree of symptom correlation present during the occurrence of symptoms. A total of 1,822 reflux episodes were detected by pH/MII, 45% of which were nonacidic. The mean SI increased using pH/MII (35.7 +/- 28.5) compared to pH probe alone (14.6 +/- 18.9; p= 0.002); no differences in the mean SSI using pH/MII compared to pH probe alone were identified. Significantly more patients had a positive SI using pH/MII than pH probe alone (p= 0.035); there was no difference in the number of patients with a positive SSI using pH/MII compared to pH probe alone. Multivariate analysis revealed that symptoms occurred more frequently when the reflux was nonacidic, mixed, and full column. Also, younger children were more likely to have the simultaneous occurrence of symptoms and reflux. Nonacid reflux may be an important predictor of respiratory symptoms. pH/MII provided important information in the evaluation of children with intractable respiratory symptoms.

Economic Evaluation of Ribosomal Immunotherapy in Patients with Chronic Ear, Nose and Throat and Respiratory Tract Infections

This study analyses the economic value of ribosomal immunotherapy in patients with chronic ear, nose and throat (ENT) infections and respiratory tract infections (RTI) as compared with patients not receiving prophylaxis. Specifically, the objective was to determine whether the incremental costs of ribosomal immunotherapy could be offset by healthcare savings through a reduction in recurrent episodes of acute infection. The study was conducted from the payer perspective in the Italian healthcare setting. A 6-month time-frame was used in the decision analysis model, and costs reflect 1995 values. The model incorporated international clinical trial data and Italian resource use data for adult patients with chronic sinusitis and bronchitis and children with recurrent ENT infections. The findings indicate that ribosomal immunotherapy is capable of generating net direct cost savings over 6 months ranging between 280 000 and 1 100 000 Italian lire (L) per patient (L1700 approximately $US1) depending on the type of chronic disease studied (otitis media or rhinopharyngitis in children, sinusitis or bronchitis in adults). Threshold incremental efficacy of immunoprophylaxis required to achieve cost equivalence compared with no prophylaxis ranged between 2 and 20%, depending on the indication and the magnitude of treatment cost associated with an acute infectious episode (low/best/high estimate) considered. In view of the incremental efficacy rates observed in clinical trials ranging between 40 and 65% for patients with ribosomal immunoprophylaxis, prevention of recurrent ENT infections and RTI appears to be an economically meaningful therapeutic strategy, even when assuming that efficacy rates achievable in real clinical practice may be lower than those reported in clinical trials. On the basis of these findings for Italy, physicians should give increased attention to ribosomal immunoprophylaxis of chronic respiratory diseases in children and adults.

Epidemiology of Chronic Lung Diseases in Children

In the introduction of this brief book, the author states that the purpose of this review is to assess current epidemiologic knowledge of chronic respiratory diseases in children, which are not known to be of infectious origin. This objective has been largely attained. The diseases considered are bronchial asthma, sarcoidosis, cystic fibrosis, hyaline membrane disease, bronchiectasis, and lobar emphysema. Not included are chronic respiratory distress in the premature infant (Wilson-Mikity syndrome) and some other diseases which occur in children but are more often seen in adults, such as desquamative interstitial pneumonia, pulmonary alveolar proteinosis, and idiopathic diffuse interstitial fibrosis of the lung (Hamman-Rich syndrome). Since asthma is by far the most common of the diseases under discussion, it seems appropriate that much of the book (49 of 137 pages) is devoted to that subject. The discussion of the epidemiology of asthma is extensive and includes mortality, incidence and prevalence, sex,