Management Of Obstructive Lung Disease Research Articles

Clinical applications of forced oscillation technique (FOT) for diagnosis and management of obstructive lung diseases in children.

Obstructive lung diseases such as bronchial asthma, COPD, and cystic fibrosis are a burden on many patients across the globe. Spirometry is considered the gold standard for diagnosing airflow obstruction, but it can be difficult for pediatric patients to do and requires a lot of effort. As a result, healthcare providers need new, effortless methods to diagnose airway obstructions, particularly in young children and individuals unable to perform the spirometry maneuver. The forced oscillation technique is a modern method requiring only tidal breathing combined with the application of external, source of low-amplitude oscillations to evaluate the respiratory system's response. It might be essential for identifying early respiratory changes caused by smoking, childhood asthma, and may prove more sensitive than spirometry in identifying peripheral airway disturbances or evaluating the long-term success of therapy. This review describes the methodology and the indications for the forced oscillation technique and outlines its relevance in clinical practice.

Association between Inhalation Instruction Method in Community Pharmacies and Inhaler Device Handling Error in Patients with Obstructive Lung Disease: An Evaluation of the Impact of Practical Demonstration by Pharmacists.

Inhaler devices play an important role in the management of obstructive lung diseases including asthma, chronic obstructive pulmonary disease (COPD), and asthma-COPD overlap. Some of these patients show suboptimal inhaler techniques; however, time for inhaler instruction by pharmacists is limited in daily clinical practice. Therefore, sufficient education regarding inhaler device handling should be provided within a limited time frame. The current study aimed to investigate the instruction methods provided by community pharmacists and their influence on inhaler device handling techniques in outpatient clinical care settings. We retrospectively collected the data of outpatients with obstructive lung diseases who were referred to our hospital and who underwent inhalation technique assessments conducted by community pharmacists. The prevalence of handling errors, clinical characteristics of patients, and instruction methods were analyzed. In total, 138 patients (170 devices) were included in this study. Approximately 70.0% of patients received verbal explanations combined with leaflets about inhaler instructions. In a device-based analysis, 63 (37.1%) of 170 devices had at least one technical error and 18 (10.6%) of the devices had critical errors. Patients without critical errors received practical demonstration instructions from pharmacists combined with leaflets and verbal explanations more frequently than those with critical errors (22.8 vs. 0%, p < 0.01). This study revealed that patients with obstructive lung diseases commonly present with inhaler device handling errors and critical errors were observed with non-negligible frequency in daily practice in Japan. Combined instruction with leaflet, verbal explanation, and pharmacist demonstration may be effective in improving proper inhaler treatment.

The Obstructive Lung Diseases Program: Integrated obstructive lung disease services within primary care in Pakistan.

Objective:To assess the learning impact of e-curriculums on healthcare professionals (HCPs). The second objective was to report the screening, detection and clinical features of patients with obstructive lung diseases (OLD) through an integrated care program at The Indus Hospital & Health Network (IHHN), Karachi, Pakistan.Methods:A retrospective, observational study was conducted in the Family Medicine outpatient department from January 2019 till July 2021. HCPs were trained on the diagnosis and management of OLD through e-learning. Patients were screened clinically for OLD and had spirometry performed if suspect. Baseline characteristics, patient-reported outcome measures (PROMs), spirometry and treatment modalities were collected. Univariate analysis was done on Excel and paired t-testing was performed on Stata 16.Results:Online training on clinical aspects of OLD was completed by 33 HCPs, amongst whom 77.9% demonstrated improved post-test evaluations of 26.8% (p=0.000). Of 1896 patients screened, 60.8% were diagnosed as OLD. Asthmatics accounted for 66.5% (60.9% females, median age 39 years). In 84.5% of patients who completed PROMs, poor control of symptoms was reported. Inhaler technique was taught in 66.5%. Breathless patients, with a high modified Medical Research Council score (mMRC ≥ 2, n=234), were referred for pulmonary rehabilitation in 92% of cases. Tobacco cessation advice was delivered to 61.1% of all current users (n=229).Conclusion:The OLD program uses capacity building, gold standard diagnostics and updated management strategies in primary care, allowing earlier diagnosis of suspected patients and implementation of evidence-based interventions, aiming to improve their morbidity and mortality.

Incident obstructive lung disease and mortality among people with HIV and a history of injecting drugs.

People with HIV (PWH) experience increased prevalence of obstructive lung disease (OLD), regardless of greater observed smoking behaviors. We investigated whether the effect of incident OLD on mortality differed by HIV and HIV viral suppression among persons who inject drugs (PWID) and report smoking history. ALIVE is a longitudinal, observational cohort study of HIV-positive and seronegative PWID. This analysis included participants who had at least one spirometry measure to assess OLD between 2007 and 2016, excluding those who never smoked (5%, n = 62) or had baseline OLD (17%, n = 269). Incident OLD occurred when the first prebronchodilator forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) less than 0.70 during follow-up. The effect of incident OLD on all-cause mortality was estimated in PWH and seronegative participants using inverse-probability-of-treatment-weighted marginal structural models controlling for baseline (age, race, sex, calendar year, smoking pack-years) and time-varying (smoking intensity, viral suppression, and calendar time) confounders. Among 1204 participants, 269 (22.3%) and 157 (13.0%) experienced incident OLD and death, respectively, over a median of five person-years of follow-up. There was no effect of OLD on mortality among seronegative participants [hazard ratio = 0.84, 95% confidence interval (CI): 0.47-1.48]; however, PWH diagnosed with OLD experienced an increased mortality risk (hazard ratio = 1.71, 95% CI: 1.04-2.80) during follow-up. HIV viral suppression did not confound or modify the effect of OLD on mortality among PWH. There was an apparent effect of OLD on all-cause mortality irrespective of viral suppression among PWH but not among seronegative persons, after accounting for baseline and time-varying confounders. These results highlight the need for enhanced screening and management of OLD among PWH.

Blood eosinophil count in patients with COPD on inhaled corticosteroids in comparison with healthy smoker and nonsmoker controls

Background Chronic obstructive pulmonary disease (COPD) is associated with acute and chronic pulmonary inflammation in the lung and as a systemic inflammation. The blood eosinophil counts are now recommended by the Global Initiative for the Management of Obstructive Lung Disease as a guide of inhaled corticosteroid use in clinical practice, as it can predict its effect on the rate of COPD exacerbation. The increasing peripheral blood eosinophilic count in patients with COPD could explain the systemic eosinophilia in COPD, which causes increased lung eosinophil count in these patients, especially those on inhaled corticosteroids (ICS). Patients and methods The study included 56 patients with COPD who were active smokers with pack-years beyond 10 as cases. The control group includes 60 patients as healthy nonsmokers (HNS) and 66 patients as healthy current smokers (HS), with pack-year beyond 10. Prebronchodilator and postbronchodilator spirometry was done in the pulmonary function unit of the Chest Department, Ain Shams University Hospital, to confirm or to exclude the COPD diagnosis. The COPD cases were categorized as per the Global Initiative for the Management of Obstructive Lung Disease severity assessment guideline and were receiving budesonide 800 μg/day and formoterol 24 μg/day or salmeterol 100 μg and fluticasone propionate 500 μg twice daily. Skin prick test and complete blood count for its differential and eosinophil count were done for all cases. Results The study included 56 patients with COPD who were active smokers and received ICS. The control group included 60 patients as HNS along with 66 patients as healthy current smokers. The HNS group showed the least total leukocytic count of 5588.33±1081.13/µl and the least eosinophilic count of 99.47±91.51/µl, whereas the COPD group showed the highest total leukocytic count. A statistically significant relation was found also between COPD patients’ eosinophil count and the use of ICS, with P value 0.000. Conclusion The peripheral blood eosinophil counts collected from patients with COPD on ICS are significantly higher than the patients with COPD who are not using ICS and the healthy smoker and nonsmoker control group.

EVALUATION OF SMALL AIRWAY REVERSIBILITY AMONG ASTHMATIC PATIENTS WITH NON-OBSTRUCTIVE PATTERNS OF SPIROMETRY

Background: Although the forced expiratory flow parameters are increasingly used in the diagnosis of small airway disease (SAD), the reversibility of these indicators is rarely described. The aim of this study is to evaluate the association of small airways reversibility with the presence of SAD and bronchodilator reversibility (BDR) of the proximal airways. Methods: The forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), and the indicators of SAD (FEF25%, FEF50%, FEF75%, FEF25-75%, and FEF75-85%) were measured before and 20 minutes after salbutamol administration (200 mcg by using inhaler/Spacer). Positive BDR was accepted when FEV1 or FVC was increased ? 12% and &gt; 200 ml, indicating responsive proximal airways. Positive small airway reversibility was diagnosed when any of the small airway indicators is increased ? 30% above the baseline results. All measurements were performed with the All-flow spirometer (Clement Clarke International, Harlow, UK). Results: Evidence of SAD was found in 62.1% of all participants and in 75.2% of those who showed responsive proximal airways. The positive predictive value of the SAD in diagnosing responsive proximal airways was 67.8%. The reversibility of the small airway indicators showed insignificant association with the FEV1 or FVC BDR. The reversibility of FEF50%, FEF75% and FEF25-75% showed significant association with the diagnosis of SAD, with specificities ranging from 75.5%-81.1%. Conclusion: SAD has a significant association with positive reversibility of both the proximal and the peripheral airways. Further studies are needed to evaluate the clinical significance of positive small airway reversibility in the diagnosis and management of obstructive lung diseases. Keywords: Asthma; Small airway disease; Bronchodilator Reversibility, FEV1, FVC; FEF25-75%

Use of endotracheal isoproterenol for severe bronchospasm while weaning from cardiopulmonary bypass

Introduction Weaning from cardiopulmonary bypass (CPB) is a complex process that focuses on cardiac function and rhythm, but adequate pulmonary function is also essential. We will present a case in which severe bronchospasm posed a substantial threat to the weaning process, but it was responsive to a novel treatment, endotracheal isoproterenol, in addition to intravenous ketamine and inhaled albuterol. Methods Case Report. Results 36-year old male with a history of Tetralogy of Fallot and asthma who presented with right-sided heart failure secondary to pulmonary stenosis and subsequent severe tricuspid regurgitation was initially managed with transcatheteter pulmonic valve placement and then scheduled for a surgical tricuspid valve replacement. CPB weaning was complicated by inability to ventilate due to severe bronchospasm, which was managed with isoproterenol (120mcg in divided dosing via endotracheal tube), ketamine, and albuterol. This treatment resulted in adequate ventilation and consequently, a successful wean without tachyarrhythmias or hypotension. Discussion This case demonstrated treating bronchospasm while weaning from CPB with a novel administration route of a largely abandoned medication in the United States. Isoproterenol causes relaxation of bronchial smooth muscle amongst other effects including increasing heart rate/contractility and peripheral vasodilation, which could potentiate arrhythmias and hypotension1. These adverse effects could be detrimental following CPB but the risk may be drastically reduced by endotracheal tube administration. Notably, treatment of the pediatric population with asthma exacerbations in the 1970s with intravenous isoproterenol found associations with arrhythmias2. However, recent data with inhalation isoproterenol has demonstrated safety in addition to increased efficacy compared to inhalation salbutamol3. Thus, more research is needed to evaluate if endotracheal isoproterenol should be utilized for management of obstructive lung disease in the OR.

Recent Advances in Interventional Pulmonology.

The field of interventional pulmonology has grown rapidly since first being defined as a subspecialty of pulmonary and critical care medicine in 2001. The interventional pulmonologist has expertise in minimally invasive diagnostic and therapeutic procedures involving airways, lungs, and pleura. In this review, we describe recent advances in the field as well as up-and-coming developments, chiefly from the perspective of medical practice in the United States. Recent advances include standardization of formalized training, new tools for the diagnosis and potential treatment of peripheral lung nodules (including but not limited to robotic bronchoscopy), increasingly well-defined bronchoscopic approaches to management of obstructive lung diseases, and minimally invasive techniques for maximizing patient-centered outcomes for those with malignant pleural effusion.

Regulation of ovarian cancer G protein-coupled receptor-1 expression and signaling.

Ovarian cancer G protein-coupled receptor 1 (OGR1) is a recently deorphanized G protein-coupled receptor shown to signal in response to low extracellular pH (↓pHo) or certain benzodiazepines. The pleiotropic nature of OGR1 signaling in human airway smooth muscle (HASM) cells suggests that OGR1 is a potential therapeutic target for the management of obstructive lung diseases. However, the basic pharmacological and regulatory features of OGR1 remain poorly understood. We employed model systems of heterologously expressed [human embryonic kidney 293 (HEK293) cells] or endogenous (HASM) OGR1 to assess changes in expression, subcellular localization, and signaling capabilities following acute or chronic treatment with ↓pHo or the benzodiazepines lorazepam and sulazepam. In HEK293 cells expressing OGR1, treatment with ↓pHo and/or lorazepam, but not sulazepam, caused rapid OGR1 internalization. In HASM cells, acute treatment with ↓pHo or benzodiazepines did not alter abundance of OGR1 mRNA; however, significant downregulation was observed following chronic treatment. Acute and chronic pretreatment of HASM cells with sulazepam or lorazepam resulted in receptor desensitization as demonstrated by reduced phosphorylation of vasodilator-stimulated phosphoprotein (VASP) or p42/p44 upon rechallenge. Acid (acute but not chronic) pretreatment of HASM cells induced desensitization of OGR1-mediated VASP (but not p42/p44) phosphorylation. In contrast to a recent study reporting OGR1 upregulation and sensitization in cardiac tissue subject to ischemic/acidic insult, chronic OGR1 activation in multiple model systems did not increase OGR1 expression or signaling capacity. The ability to induce OGR1 internalization and desensitization was activator dependent, reflecting the ability of different activators to induce specific receptor confirmations and engagement of specific heterotrimeric G proteins.

Assessment of Prescribing Pattern of Drugs in the Management of Obstructive Lung Diseases and Respiratory Tract Infections

Assessment of Prescribing Pattern of Drugs in the Management of Obstructive Lung Diseases and Respiratory Tract Infections

Assessment of Prescribing Pattern of Drugs in the Management of Obstructive Lung Diseases and Respiratory Tract Infections

Assessment of Prescribing Pattern of Drugs in the Management of Obstructive Lung Diseases and Respiratory Tract Infections

Applied upper-airway resistance instantly affects breath components: a unique insight into pulmonary medicine

Respiratory parameters such as flow or rate have complex effects on the exhalation of volatile substances and can hamper clinical interpretation of breath biomarkers. We have investigated the effects of progressively applied upper-airway resistances on the exhalation of volatile organic compounds (VOCs) in healthy humans. We performed real-time mass-spectrometric determination of breath volatiles in 50 subjects with parallel, non-invasive hemodynamic monitoring, breath-resolved spirometry and capnometry during controlled tidal breathing (12 breaths/min). Airway resistance was increased by changing the mouthpiece diameters from 2.5 cm to 1.0 cm and to 0.5 cm. At the smallest diameter, oxygen uptake increased (35%↑). Cardiac output decreased (6%↓) but end-tidal PCO2 (8%↑) and exhalation of blood-borne isoprene (19%↑) increased. Carbon dioxide production remained constant. Furan, hydrogen sulphide mirrored isoprene. Despite lowered minute ventilation (4%↓) acetone concentrations decreased (3%↓). Exogenous acetonitrile, propionic acid, isopropanol, limonene mimicked acetone. VOC concentration changes could be modelled through substance volatility. Airway resistance-induced changes in hemodynamics, and ventilation can affect VOC exhalation and thereby interfere with breath biomarker interpretation. The effects of collateral ventilation, intra-alveolar pressure gradients and respiratory mechanics had to be considered to explain the exhalation kinetics of CO2 and VOCs. Conventional breath sampling via smaller mouthpiece diameters (≤1.0 cm, e.g. via straw in Tedlar bags or canisters, etc) will immediately affect VOC exhalation and thereby mislead the analysis of the obtained results. Endogenous isoprene may probe respiratory muscle workload under obstructive conditions. Breath-gas analysis might enhance our understanding of diagnosis and management of obstructive lung diseases in the future.

Impact of exacerbations on respiratory system impedance measured by a forced oscillation technique in COPD: a prospective observational study.

BackgroundForced oscillation technique (FOT) has been reported to be useful in the evaluation and management of obstructive lung disease, including COPD. To date, no data are available concerning long-term changes in respiratory system impedance measured by FOT. Additionally, although exacerbations have been reported to be associated with excessive lung function decline in COPD, the impact of exacerbations on the results of FOT has not been demonstrated. The aim of this study was to investigate the longitudinal changes in respiratory system impedance and the influence of exacerbations thereon.MethodsBetween March 2011 and March 2012, outpatients who attended Kobe City Medical Center West Hospital with a diagnosis of COPD were assessed for eligibility. Baseline patient characteristics (age, sex, body mass index, smoking history, current smoking status, COPD stage), lung function (post-bronchodilator forced expiratory volume in 1 second [FEV1]), blood tests (neutrophils and eosinophils), FOT, and COPD assessment test results were collected at enrollment. Lung function and FOT were examined every 6 months until March 2016. Annual changes in FEV1 and FOT parameters were obtained from the slope of the linear regression curve. The patients were divided into 2 groups based on exacerbation history.ResultsFifty-one of 58 patients with COPD were enrolled in this study. The median follow-up period was 57 (52–59) months. Twenty-five (49%) patients experienced exacerbations. A significant annual decline in FEV1 and respiratory system impedance were shown. Additionally, annual changes in FEV1, respiratory system resistance at 5 Hz, respiratory system reactance at 5 Hz, and resonant frequency were greater in patients with exacerbations than in those without exacerbations.ConclusionExacerbations of COPD lead not only to a decline in lung function but also to an increase in respiratory system impedance.

Lung ventilation scintigraphy in the assessment of obstructive lung diseases

Educational aimsTo describe more recent techniques used to study the regional distribution of ventilation.To learn the most frequent abnormal patterns of lung ventilation scintigraphy (LVS) in obstructive lung diseases.To compare the information obtained by this technique with that obtained by traditional lung function tests.To understand that LVS may provide further information on lung pathophysiology.SummaryLVS is a well known technique that is used to study the distribution of ventilation in pulmonary diseases. However, its application in current practice has been poorly developed, mainly because of methodological problems. Redistribution of convective ventilation is the leading disorder in patients with chronic obstructive pulmonary disease (COPD) and is the target of most treatments, either by drugs or mechanical ventilation. The current availability of a new delivery inhaler (FAI; Medical Products Research, Legnano, Italy) with fine particles allows: 1) fast aerosol administration; 2) high-quality early images; 3) improved visualisation of pulmonary periphery; and 4) wider physiological distribution of the radioaerosol. Several patterns of distribution of pulmonary ventilation can be described in different airway disorders (asthma and COPD). These abnormalities are often too subtle to be picked up by traditional lung function tests, both in the baseline evaluation and after different interventions. Wider use of this technique may increase the knowledge and the management of obstructive lung diseases.

Spirometry Can Be Done in Family Physicians' Offices and Alters Clinical Decisions in Management of Asthma and COPD

Spirometry is recommended for diagnosis and management of obstructive lung disease. While many patients with asthma and COPD are cared for by primary care practices, limited data are available on the use and results associated with spirometry in primary care. To assess the technical adequacy, accuracy of interpretation, and impact of office spirometry. A before-and-after quasiexperimental design. Three hundred eighty-two patients from 12 family medicine practices across the United States. Patients with asthma and COPD, and staff from the 12 practices. Technical adequacy of spirometry results, concordance between family physician and pulmonary expert interpretations of spirometry test results, and changes in asthma and COPD management following spirometry testing. Of the 368 tests completed over the 6 months, 71% were technically adequate for interpretation. Family physician and pulmonary expert interpretations were concordant in 76% of completed tests. Spirometry was followed by changes in management in 48% of subjects with completed tests, including 107 medication changes (>85% concordant with guideline recommendations) and 102 nonpharmacologic changes. Concordance between family physician and expert interpretations of spirometry results was higher in those patients with asthma compared to those with COPD. US family physicians can perform and interpret spirometry for asthma and COPD patients at rates comparable to those published in the literature for international primary care studies, and the spirometry results modify care.

A critical evaluation of the guidelines of obstructive lung disease and their implementation

Guidelines or recommendations for diagnosis and treatment of obstructive lung diseases defined as asthma and/or chronic obstructive pulmonary disease (COPD) have been numerous in the Nordic countries during the last 25 years. A better-shared care between on one side the general practitioners or chest physicians and on the other side the patients and their closest surroundings of care has to be implemented in future guidelines. Guidelines are based on efficacy and not effectiveness studies, and do not properly focus the process of behavioural changes of health care professionals and patients. Primary care physicians treat the vast majority of patients with chronic airway disease of moderate severity. However, they find the evidence-based practice guidelines often complicated. Furthermore, less than 50% of the recommendations in guidelines may be evidence based. As rapid changes may occur in diagnosis and treatment options, future guidelines must be able to adapt to such rapid adjustments. No randomised studies are available on the effect of patient-relevant outcomes using guidelines on management of obstructive lung disease. More outcome research is necessary on both change of procedures and health endpoints after launching guidelines. Cost-effectiveness studies are important to make medical staff and administrative health care systems cooperate in the construction of future health care systems with both an improved medical and system quality.

Spirometry in the Primary Care Setting

To determine if screening spirometry in the primary care setting influences the physician's diagnosis and management of obstructive lung disease. Diagnosis and management assessed before and after the intervention of screening spirometry. A total of 1,034 patients who had ever smoked and were at least 35 years of age presenting to primary care practices for any reason. Rural primary care practices. Physicians were asked prior to and following presentation of spirometry test results if they thought airflow obstruction was present and if they planned to change management based on the results. A new diagnosis of unsuspected airflow obstruction was made by the physician in 93 patients (9%), and a prior diagnosis of airflow obstruction was removed after spirometry in 115 patients (11%). After viewing the spirometry results, physicians reported that they would change patient management in 154 patients (15%). Most planned management changes occurred when airflow obstruction was newly diagnosed (57 of 93 patients, 61%) and when the diagnosis of airflow obstruction remained unchanged (80 of 195 patients, 41%). A 6-month chart review documented the addition of respiratory medications in 8% of patients. Screening spirometry influences physicians' diagnosis of airflow obstruction and management plans especially in patients with moderate-to-severe obstruction.

Implementation of GOLD Guideline Interventions for COPD in the Outpatient Setting

PURPOSE: Implementing “best practice” for COPD as outlined in guidelines from the Global Initiative for the Diagnosis and Management of Obstructive Lung Disease (GOLD) would likely have an impact in the prevention, morbidity and cost of COPD. Yet, “usual care” seldom achieves guideline care. This abstract describes successful implementation of clinical practice tools based on the GOLD interventions, and showed improved rates of guideline care.

Forced spirometry reference values for Norwegian adults: the Bronchial Obstruction in Nord-Trøndelag Study.

The purpose of this study was to develop new prediction equations for flow/volume spirometry parameters in asymptomatic, never-smoking adults in Norway, and to assess any differences of these parameters when applying the new and most commonly used equation sets. Flow/volume spirometry was measured according to the American Thoracic Society criteria in 2,792 subjects aged > or = 20 yrs, randomly selected from participants in the Nord-Trøndelag Health Study. Ever-smokers and subjects with respiratory symptoms and/or diseases reported in this questionnaire were excluded. A total of 546 females and 362 males met the inclusion criteria and were included in the analyses. Most lung function variables were nonlinear by age and had to be transformed. After a plateau in younger adults, the variables declined by age. The reference values for forced expiratory volume in one second and forced vital capacity from the present study, were higher than those given by prediction equations from the European Community for Coal and Steel, but in closer agreement with later studies from Europe, Australia and the USA. Healthcare providers should be encouraged to reconsider their choice of prediction equations of spirometry in order to improve management of obstructive lung diseases.

Trends in asthma and chronic obstructive pulmonary disease therapy in Canada, 1985 to 1990

Background: In the mid and late 1980s, numerous changes were recommended in the management of obstructive lung diseases. We analyzed drug sales to determine whether these recommendations have resulted in recent changes in prescription drugs used in airway management. Methods: Data on prescription sales in Canada from 1985 to 1990 were obtained from an international pharmaceutical market research organization. Data from a random sampling of physicians that reported patients seen along with the diagnosis and prescriptions given were also reviewed. Results: From 1985 to 1990, there was a 38% increase in prescriptions of all airway drugs. Prescriptions increased significantly for inhaled drugs as follows: inhaledβ 2-agonists, 70%; inhaled steroids, 139%; cromoglycate, 88%; and ipratropium bromide, 204%. Theophylline prescriptions, by contrast, fell significantly, by 19%. Although theophylline was the most commonly prescribed airway medication in 1985, inhaledβ 2-agonists were the most commonly prescribed drug in 1990, and these changes in proportional use were significant. Increases in ipratropium bromide usage was accounted for by increases in prescriptions for chronic obstructive pulmonary disease. Increases in nonsteroidal antiinflammatory drugs were accounted for by asthma prescriptions. Conclusions: The increase in airway medication prescriptions dispensed in Canada is consistent with an increase in the number of patients treated, an increase in the severity of disease treated, or both.