Association between lung function and sleep disorder symptoms in a community-based multi-site case-finding study.

Obstructive airway disease is associated with sleep disturbances. We aimed to assess the relationship between lung function and sleep disorder symptoms using cross-sectionally collected data between March 2017 and August 2021 from the Undiagnosed Chronic Obstructive Pulmonary Disease and Asthma Population study, a prospective community-based multi-site case-finding study. Undiagnosed Chronic Obstructive Pulmonary Disease and Asthma Population study participants with respiratory symptoms but without diagnosed lung disease who completed spirometry and the Global Sleep Assessment Questionnaire were included.

Impact of Dyspnea on Adults With Respiratory Symptoms Without a Defined Diagnosis.

Background: We investigated dyspnea; its associated risk factors; and its impact on health care utilization, quality of life, and work productivity in adults with undiagnosed respiratory symptoms.

Research Question: What is the impact of dyspnea in adults with undiagnosed respiratory symptoms?

Study Design And Methods: This population-based study included 2,857 adults who were experiencing respiratory symptoms. These individuals had not been previously diagnosed with any lung conditions and were recruited from 17 Canadian centers using random digit dialing.

Early Diagnosis and Treatment of COPD and Asthma - A Randomized, Controlled Trial.

Background: Many persons with chronic obstructive pulmonary disease (COPD) or asthma have not received a diagnosis, so their respiratory symptoms remain largely untreated.

Methods: We used a case-finding method to identify adults in the community with respiratory symptoms without diagnosed lung disease. Participants who were found to have undiagnosed COPD or asthma on spirometry were enrolled in a multicenter, randomized, controlled trial to determine whether early diagnosis and treatment reduces health care utilization for respiratory illness and improves health outcomes.

Impact of Undiagnosed Chronic Obstructive Pulmonary Disease and Asthma on Symptoms, Quality of Life, Healthcare Use, and Work Productivity.

A significant proportion of individuals with chronic obstructive pulmonary disease (COPD) and asthma remain undiagnosed. The objective of this study was to evaluate symptoms, quality of life, healthcare use, and work productivity in subjects with undiagnosed COPD or asthma compared with those previously diagnosed, as well as healthy control subjects. This multicenter population-based case-finding study randomly recruited adults with respiratory symptoms who had no previous history of diagnosed lung disease from 17 Canadian centers using random digit dialing.

Airway inflammation and hyperresponsiveness in subjects with respiratory symptoms and normal spirometry.

Background: Subjects without a previous history of asthma, presenting with unexplained respiratory symptoms and normal spirometry, may exhibit airway hyperresponsiveness (AHR) in association with underlying eosinophilic (type 2 (T2)) inflammation, consistent with undiagnosed asthma. However, the prevalence of undiagnosed asthma in these subjects is unknown.

Methods: In this observational study, inhaled corticosteroid-naïve adults without previously diagnosed lung disease reporting current respiratory symptoms and showing normal pre- and post-bronchodilator spirometry underwent fractional exhaled nitric oxide ( ) measurement, methacholine challenge testing and induced sputum analysis.

Patient and physician factors associated with symptomatic undiagnosed asthma or COPD.

Background: It remains unclear why some symptomatic individuals with asthma or COPD remain undiagnosed. Here, we compare patient and physician characteristics between symptomatic individuals with obstructive lung disease (OLD) who are undiagnosed and individuals with physician-diagnosed OLD.

Methods: Using random-digit dialling and population-based case finding, we recruited 451 participants with symptomatic undiagnosed OLD and 205 symptomatic control participants with physician-diagnosed OLD.

Disease burden in individuals with symptomatic undiagnosed asthma or COPD.

Background: The actual burden of COPD and asthma may be much higher than appreciated, since a large proportion of individuals are not diagnosed. Our study objective was to compare health care utilization, burden of symptoms and quality of life in subjects with self-reported respiratory symptoms who were subsequently found to have undiagnosed airflow obstruction compared to those having no airflow obstruction.

Methods: This cross-sectional case-finding study used data from the Undiagnosed COPD and Asthma Population (UCAP) study.

Derivation and validation of the UCAP-Q case-finding questionnaire to detect undiagnosed asthma and COPD.

Background: Many people with asthma and COPD remain undiagnosed. We developed and validated a new case-finding questionnaire to identify symptomatic adults with undiagnosed obstructive lung disease.

Methods: Adults in the community with no prior history of physician-diagnosed lung disease who self-reported respiratory symptoms were contacted random-digit dialling.

Population-based case-finding to identify subjects with undiagnosed asthma or COPD.

Background: ∼5-10% of adults may have undiagnosed airflow obstruction. The objective of this study was to develop a population-based case-finding strategy to assess the prevalence of undiagnosed airflow obstruction (asthma or COPD) amongst adults with respiratory symptoms in Canada.

Methods: Adults without a previous history of asthma, COPD or lung disease were recruited using random digit-dialling and asked if they had symptoms of dyspnoea, cough, sputum or wheeze within the past 6 months.

Performance Characteristics of Spirometry With Negative Bronchodilator Response and Methacholine Challenge Testing and Implications for Asthma Diagnosis.

Background: In patients with a history suggestive of asthma, diagnosis is usually confirmed by spirometry with bronchodilator response (BDR) or confirmatory methacholine challenge testing (MCT).

Research Question: We examined the proportion of participants with negative BDR testing who had a positive MCT (and its predictors) result and characteristics of MCT, including effects of controller medication tapering and temporal variability (and predictors of MCT result change), and concordance between MCT and pulmonologist asthma diagnosis.

Study Design And Methods: Adults with self-reported physician-diagnosed asthma were recruited by random-digit dialing across Canada.

Placebo Effects in Clinical Trials Evaluating Patients with Uncontrolled Persistent Asthma.

Patients with uncontrolled, persistent asthma can show substantial health improvements when administered placebo. We analyzed five randomized, placebo-controlled clinical trials that assessed subjects with uncontrolled, persistent asthma to determine the magnitudes of placebo effects across different clinical outcomes. Placebo effects for objective asthma-related outcomes, healthcare utilization outcomes, and patient-reported outcomes were estimated, with adjustments for regression to the mean.

Between-Visit Variability in FEV as a Diagnostic Test for Asthma in Adults.

Rationale: The reliability of using between-visit variation in forced expiratory volume in 1 second (FEV) to diagnose asthma is understudied, and hence uncertain.

Objective: To determine whether FEV variability measured over recurrent visits is significantly associated with a diagnosis of current asthma.

Methods: Randomly selected adults (N = 964) with a history of physician-diagnosed asthma were studied from 2005 to 2007 and from 2012 to 2016.

Reevaluation of Diagnosis in Adults With Physician-Diagnosed Asthma.

Importance: Although asthma is a chronic disease, the expected rate of spontaneous remissions of adult asthma and the stability of diagnosis are unknown.

Objective: To determine whether a diagnosis of current asthma could be ruled out and asthma medications safely stopped in randomly selected adults with physician-diagnosed asthma.

Design, Setting, And Participants: A prospective, multicenter cohort study was conducted in 10 Canadian cities from January 2012 to February 2016.

Effects of weight loss on airway responsiveness in obese adults with asthma: does weight loss lead to reversibility of asthma?

Background: The growing epidemics of obesity and asthma are major public health concerns. Although asthma-obesity links are widely studied, the effects of weight loss on asthma severity measured by airway hyperresponsiveness (AHR) have received limited attention. The main study objective was to examine whether weight reduction reduces asthma severity in obese adults with asthma.

Implementation of a cystic fibrosis lung transplant referral patient decision aid in routine clinical practice: an observational study.

Background: The decision to have lung transplantation as treatment for end-stage lung disease from cystic fibrosis (CF) has benefits and serious risks. Although patient decision aids are effective interventions for helping patients reach a quality decision, little is known about implementing them in clinical practice. Our study evaluated a sustainable approach for implementing a patient decision aid for adults with CF considering referral for lung transplantation.

Acute effects of viral respiratory tract infections on sputum bacterial density during CF pulmonary exacerbations.

Background: Airway proliferation of Pseudomonas aeruginosa bacteria is thought to trigger CF exacerbations and may be affected by the presence of viral infections.

Methods: A 2-year prospective study was conducted on 35 adults with CF. P.

Effect of infection with transmissible strains of Pseudomonas aeruginosa on lung transplantation outcomes in patients with cystic fibrosis.

Background: Compared with patients infected with unique strains of Pseudomonas aeruginosa, patients with cystic fibrosis who are infected with transmissible strains of P aeruginosa, such as the Liverpool epidemic strain, have a 3-fold greater risk of death or lung transplant. We aimed to determine if pre-operative infection with transmissible strains of P aeruginosa was similarly associated with poor health outcomes after lung transplant.

Methods: We had prospectively identified and characterized endobronchial infections in 446 adult cystic fibrosis patients in Ontario, Canada, from September 2005 until December 2009.

TNFα antagonists for acute exacerbations of COPD: a randomised double-blind controlled trial.

Background: The purpose of this randomised double-blind double-dummy placebo-controlled trial was to investigate whether etanercept, a tumour necrosis factor α (TNFα) antagonist, would provide more effective anti-inflammatory treatment for acute exacerbations of chronic obstructive pulmonary disease (COPD) than prednisone.

Methods: We enrolled 81 patients with acute exacerbations of COPD and randomly assigned them to treatment with either 40 mg oral prednisone given daily for 10 days or to 50 mg etanercept given subcutaneously at randomisation and 1 week later. Both groups received levofloxacin for 10 days plus inhaled bronchodilators.

Treatment of Aspergillus fumigatus in patients with cystic fibrosis: a randomized, placebo-controlled pilot study.

Background: Many patients with cystic fibrosis develop persistent airway infection/colonization with Aspergillus fumigatus, however the impact of A. fumigatus on clinical outcomes remains unclear. The objective of this study was to determine whether treatment directed against Aspergillus fumigatus improves pulmonary function and clinical outcomes in patients with cystic fibrosis (CF).

Exacerbation frequency and clinical outcomes in adult patients with cystic fibrosis.

Background: Despite advances in treatment of cystic fibrosis (CF), pulmonary exacerbations remain common. The aim of this study was to determine if frequent pulmonary exacerbations are associated with greater declines in lung function, or an accelerated time to death or lung transplantation in adults with CF.

Methods: A 3-year prospective cohort study was conducted on 446 adult patients with CF from Ontario, Canada who could spontaneously produce sputum.

(Correcting) misdiagnoses of asthma: a cost effectiveness analysis.

Background: The prevalence of physician-diagnosed-asthma has risen over the past three decades and misdiagnosis of asthma is potentially common.

Objective: to determine whether a secondary-screening-program to establish a correct diagnosis of asthma in those who report a physician diagnosis of asthma is cost effective.

Method: Randomly selected physician-diagnosed-asthmatic subjects from 8 Canadian cities were studied with an extensive diagnostic algorithm to rule-in, or rule-out, a correct diagnosis of asthma.

Infection with transmissible strains of Pseudomonas aeruginosa and clinical outcomes in adults with cystic fibrosis.

Context: Studies from Australia and the United Kingdom have shown that some patients with cystic fibrosis are infected with common transmissible strains of Pseudomonas aeruginosa.

Objectives: To determine the prevalence and incidence of infection with transmissible strains of P. aeruginosa and whether presence of the organism was associated with adverse clinical outcomes in Canada.

Multi analyte profiling and variability of inflammatory markers in blood and induced sputum in patients with stable COPD.

Background: We analyzed serial concentrations of multiple inflammatory mediators from serum and induced sputum obtained from patients with stable COPD and controls. The objective was to determine which proteins could be used as reliable biomarkers to assess COPD disease state and severity.

Methods: Forty-two subjects; 21 with stable COPD and 21 controls, were studied every 2 weeks over a 6-week period.