R. Andrew McIvor

Overdiagnosis of asthma in obese and nonobese adults

Background: It is unclear whether asthma is overdiagnosed in developed countries, particularly among obese individuals, who may be more likely than nonobese people to experience dyspnea. Methods: We conducted a longitudinal study involving nonobese (body mass index 20–25) and obese (body mass index ≥ 30) individuals with asthma that had been diagnosed by a physician. Participants were recruited from 8 Canadian cities by means of random-digit dialing. A diagnosis of current asthma was excluded in those who did not have evidence of acute worsening of asthma symptoms, reversible airflow obstruction or bronchial hyperresponsiveness, despite being weaned off asthma medications. We stopped asthma medications in those in whom a diagnosis of asthma was excluded and assessed their clinical outcomes over 6 months. Results: Of 540 individuals with physician-diagnosed asthma who participated in the study, 496 (242 obese and 254 nonobese) could be conclusively assessed for a diagnosis of asthma. Asthma was ultimately excluded in 31.8% (95% confidence interval [CI] 26.3%–37.9%) in the obese group and in 28.7% (95% CI 23.5%–34.6%) in the nonobese group. Overdiagnosis of asthma was no more likely to occur among obese individuals than among nonobese individuals (p = 0.46). Of those in whom asthma was excluded, 65.5% did not need to take asthma medication or seek health care services because of asthma symptoms during a 6-month follow-up period. Interpretation: About one-third of obese and nonobese individuals with physician-diagnosed asthma did not have asthma when objectively assessed. This finding suggests that, in developed countries such as Canada, asthma is overdiagnosed.

Asthma control in Canada remains suboptimal: The Reality of Asthma Control (TRAC) study

BACKGROUND Two Canadian studies showed that 55% of patients with asthma had daily symptoms (in 1996) and that 57% of patients suffered from poorly controlled asthma (in 1999). OBJECTIVES To assess the state of asthma control of adult Canadians, and asthma knowledge and practices of Canadian physicians actively involved in the care of patients with asthma. METHODS Telephone interviews were conducted with adults 18 to 54 years of age who had been diagnosed with asthma at least six months before the survey, who did not have chronic obstructive pulmonary disease and who had a smoking history of fewer than 20 pack-years. Physicians were surveyed by telephone and mail. The surveys took place between April and August 2004. RESULTS Almost all (97%) of the 893 patients believed that they had controlled asthma; however, only 47% had controlled disease according to symptom-based guideline criteria. Just 39% of 463 physicians based their treatment recommendations on the Canadian asthma guidelines most or all of the time, despite having a high awareness of them. Only 11% of patients had written action plans, and one-half of patients with action plans did not use them regularly. Almost three-quarters of patients expressed concerns about taking inhaled corticosteroids. CONCLUSIONS Since the last major national survey, guideline implementation has not resulted in significant changes in asthma-related morbidity. Effective means of knowledge transfer should be developed and implemented to improve the translation of guideline recommendations into care.

Atovaquone Suspension Compared with Aerosolized Pentamidine for Prevention of Pneumocystis carinii Pneumonia in Human Immunodeficiency Virus—Infected Subjects Intolerant of Trimethoprim or Sulfonamides

Atovaquone suspensions (750 mg and 1500 mg once a day) were compared with aerosolized pentamidine (300 mg once a month) for the prevention of Pneumocystis carinii pneumonia (PCP) in subjects with human immunodeficiency virus (HIV) infection who were intolerant to trimethoprim or sulfonamides (or both). Median time using the assigned therapy was 6.6 months, and the median follow-up was 11.3 months. Intent-to-treat analyses (n=549) showed no statistically significant differences among subjects with regard to the incidence of PCP (26%, 22%, and 17%, respectively) or mortality (20%, 13%, and 18%, respectively). The incidence of treatment-limiting adverse events with atovaquone was significantly higher (P<.01). There was, however, no significant difference in the time using therapy. Incidences of PCP and death were higher in subjects receiving 750 mg of atovaquone than in subjects receiving 1500 mg. Atovaquone suspension at 1500 mg once a day has an efficacy similar to that of aerosolized pentamidine for prevention of PCP in HIV-infected subjects and is a safe, effective alternative in those who are intolerant to trimethoprim or sulfonamides.

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. Random digit dialing was used to recruit adult participants who reported a history of physician-diagnosed asthma established within the past 5 years. Participants using long-term oral steroids and participants unable to be tested using spirometry were excluded. Information from the diagnosing physician was obtained to determine how the diagnosis of asthma was originally made in the community. Of 1026 potential participants who fulfilled eligibility criteria during telephone screening, 701 (68.3%) agreed to enter into the study. All participants were assessed with home peak flow and symptom monitoring, spirometry, and serial bronchial challenge tests, and those participants using daily asthma medications had their medications gradually tapered off over 4 study visits. Participants in whom a diagnosis of current asthma was ultimately ruled out were followed up clinically with repeated bronchial challenge tests over 1 year. Exposure Physician-diagnosed asthma established within the past 5 years. Main Outcomes and Measures The primary outcome was the proportion of participants in whom a diagnosis of current asthma was ruled out, defined as participants who exhibited no evidence of acute worsening of asthma symptoms, reversible airflow obstruction, or bronchial hyperresponsiveness after having all asthma medications tapered off and after a study pulmonologist established an alternative diagnosis. Secondary outcomes included the proportion with asthma ruled out after 12 months and the proportion who underwent an appropriate initial diagnostic workup for asthma in the community. Results Of 701 participants (mean [SD] age, 51 [16] years; 467 women [67%]), 613 completed the study and could be conclusively evaluated for a diagnosis of current asthma. Current asthma was ruled out in 203 of 613 study participants (33.1%; 95% CI, 29.4%-36.8%). Twelve participants (2.0%) were found to have serious cardiorespiratory conditions that had been previously misdiagnosed as asthma in the community. After an additional 12 months of follow-up, 181 participants (29.5%; 95% CI, 25.9%-33.1%) continued to exhibit no clinical or laboratory evidence of asthma. Participants in whom current asthma was ruled out, compared with those in whom it was confirmed, were less likely to have undergone testing for airflow limitation in the community at the time of initial diagnosis (43.8% vs 55.6%, respectively; absolute difference, 11.8%; 95% CI, 2.1%-21.5%). Conclusions and Relevance Among adults with physician-diagnosed asthma, a current diagnosis of asthma could not be established in 33.1% who were not using daily asthma medications or had medications weaned. In patients such as these, reassessing the asthma diagnosis may be warranted.

A Comparison of Obese and Nonobese People With Asthma Exploring an Asthma-Obesity Interaction

OBJECTIVE The objectives of our study were to compare patient characteristics and severity of disease in obese and normal-weight-confirmed people with asthma and to explore reasons for misdiagnosis of asthma, including potential interactions with obesity. METHODS We randomly selected patients with physician-diagnosed asthma from eight Canadian cities. Asthma diagnosis was confirmed via a sequential lung function testing algorithm. Logistic analysis was conducted to compare obese and normal-weight-confirmed people with asthma and to assess characteristics associated with misdiagnosis of asthma. Interaction with obesity was investigated. RESULTS Complete assessments were obtained on 496 subjects who reported physician-diagnosed asthma (242 obese and 254 normal-weight subjects); 346 had asthma confirmed with sequential lung testing, and in 150 subjects a diagnosis of asthma was ruled out. Obese subjects with asthma were significantly more likely to be men, have a history of hypertension and gastroesophageal reflux disease, and have a lower FEV(1) compared with normal-weight subjects with asthma. Older subjects, men, and subjects with higher FEV(1) were more likely to have received misdiagnoses of asthma. Obesity was not an independent predictor of misdiagnosis, however there was an interaction between obesity and urgent visits for respiratory symptoms. The odds ratio for receiving a misdiagnosis of asthma for obese individuals as compared with normal-weight individuals was 4.08 (95% CI, 1.23-13.5) for those with urgent visits in the past 12 months. CONCLUSIONS Obese people with asthma have lower lung function and more comorbidities compared with normal-weight people with asthma. Obese individuals who make urgent visits for respiratory symptoms are more likely to receive a misdiagnosis of asthma.

Management of acute asthma in adults in the emergency department: nonventilatory management

Peter, a 26-year-old man with chronic, poorly controlled asthma, presents to a walk-in clinic reporting increasing asthma symptoms over a period of one week. He has been needing up to 20 puffs of salbutamol per day. An acute exacerbation of asthma is diagnosed, and the patient is immediately

Overcoming gaps in the management of chronic obstructive pulmonary disease in older patients: new insights.

Chronic obstructive pulmonary disease (COPD) is a common disorder with a high prevalence among elderly men and women and an increasing mortality rate. Its diagnosis relies on spirometry, with a diagnostic cut-off value of a forced expiratory volume in 1 second (FEV1)/forced vital capacity ratio of <0.7. This cut-off level has received some criticism because a ratio decline is part of normal advanced aging. Thus, clinicians must be vigilant in applying appropriate diagnostic criteria when managing elderly patients and may choose to use one or more of the alternative diagnostic values that have been created.It is important to remember that COPD is a systemic disorder with several extrapulmonary manifestations. Elderly patients with COPD are at an increased risk of cardiovascular events, osteoporosis, fractures, peripheral muscle wasting, depression and anxiety. Management of these patients requires a multidisciplinary approach and should begin with stratification of disease severity and prognostic information for each patient.Traditionally, FEV1 has been used as a marker of COPD severity. However, indices such as the Modified Medical Research Council (MMRC) Dyspnoea Scale; the updated body mass, airflow, obstruction, dyspnoea and exercise (BODE) index; and the new age, dyspnoea, obstruction (ADO) index have been found to be better predictors of mortality in elderly patients.In addition to smoking cessation, supplemental oxygen and vaccines, management strategies such as patient education programmes — which have been shown to reduce hospital admissions — should not be overlooked. Pulmonary rehabilitation remains an underutilized treatment modality despite its demonstrated association with improvements in quality of life, reduced dyspnoea and increased exercise capacity. Studies have shown no correlation between age and outcomes in pulmonary rehabilitation, suggesting that age should not be an exclusion criterion. Although bronchodilators and corticosteroids remain the cornerstone of pharmaceutical management of COPD, their efficacy relies on correct medication administration. Inhaler technique should be frequently assessed in the elderly population and the choice of inhaler device needs to be tailored to the patients’ needs, situation and preferences. Assessment and management of extrapulmonary co-morbidities of COPD should also be undertaken. Careful attention to the mental health of elderly patients with COPD is also vital, as they have high rates of depression and anxiety. Furthermore, elderly patients with severe COPD receive inadequate palliative care despite the elevated mortality risk associated with this illness. Early discussion about end-of-life care and advanced care planning is recommended.

Triple Therapy for the Management of COPD: A Review

Triple therapy for COPD consists of a long-acting anti-cholinergic bronchodilator, a long-acting beta-agonist bronchodilator, and an inhaled corticosteroid. Guidelines from the Canadian Thoracic Society advocate triple therapy for some patients with moderate-to-severe COPD. The objective of this review was to evaluate the evidence based clinical efficacy of triple therapy compared to dual bronchodilator therapy (long-acting anti-cholinergic bronchodilator + beta-agonist bronchodilator) or long-acting anti-cholinergic bronchodilator monotherapy for managing COPD. A systematic literature search was conducted to identify relevant clinical evaluations of triple therapy in the management of moderate to severe COPD. Databases searched included: Medline; EMBASE; CINAHL and PubMed (non-Medline records only). Of 2,314 publications, 4 articles evaluated triple therapy for the management of COPD. Hospitalization rates for COPD exacerbations, reported in 2 trials, were significantly reduced with triple therapy compared to long-acting anti-cholinergic bronchodilator monotherapy, with reported relative risks of 0.53 (95% CI: 0.33, 0.86, p = 0.01) and 0.35 (95% CI: 0.16–0.78, p = 0.011). Exacerbation data is inconsistent between the two trials reporting this outcome. Lung function, dyspnea and quality of life data show statistical significant changes with triple therapy compared to long-acting anti-cholinergic bronchodilator monotherapy but the changes do not reach clinical importance. Triple therapy does decrease the number of hospitalizations for severe/acute COPD exacerbations compared with long-acting anti-cholinergic bronchodilator monotherapy. There is insufficient evidence to determine if triple therapy is superior to dual bronchodilator therapy.

Montelukast as an alternative to low-dose inhaled corticosteroids in the management of mild asthma (the SIMPLE trial): An open-label effectiveness trial

OBJECTIVE To evaluate the effectiveness of montelukast as monotherapy for patients with mild asthma who remain uncontrolled or unsatisfied while on inhaled corticosteroid (ICS) monotherapy. DESIGN A multicentre, open-label study. Patients (six years of age or older) had ICS therapy discontinued and were treated with orally administered montelukast once daily for six weeks. MAIN OUTCOME MEASURES The primary outcome measure was the rate at which asthma symptom control was achieved or maintained after six weeks of treatment. The secondary outcome measures were to compare compliance and physician satisfaction, and to further assess the safety and tolerability of montelukast. RESULTS Of the 534 patients enrolled, 481 (90.1%) completed the study. Mean (+/- SD) age was 27.8+/-19.0 years. The number of patients with uncontrolled symptoms decreased from 455 (85.2%) at baseline to 143 (26.8%) at week 6 (P<0.001), and mean Asthma Control Questionnaire score decreased from 1.4+/-0.8 to 0.6+/-0.6 (P<0.001), representing a clinically significant improvement. Of the 79 patients with controlled asthma symptoms at baseline, 73.4% maintained asthma control at week 6. Compliance to asthma therapy increased from 41% at baseline for ICS to 88% at week 6 for montelukast (P<0.001). Physician satisfaction with treatment increased from 43% to 85% (P<0.001) and patient satisfaction increased from 45% at baseline to 94% at week 6. No serious adverse events were reported over the course of the study. CONCLUSION Montelukast is an effective and well-tolerated alternative to ICS treatment in patients with mild asthma who are uncontrolled or unsatisfied with low-dose ICS therapy.

Detection of COPD Exacerbations and Compliance With Patient-Reported Daily Symptom Diaries Using a Smartphone-Based Information System

Background Paper-based diaries and self-report of symptom worsening in COPD may lead to underdetection of exacerbations. Epidemiologically, COPD exacerbations exhibit seasonal patterns peaking at year-end. We examined whether the use of a BlackBerry-based daily symptom diary would detect 95% or more of exacerbations and enable characterization of seasonal differences among them. Methods Fifty participants with GOLD (Global Initiative for Chronic Obstructive Lung Disease) stage I to IV COPD began a community-based study in December 2007. Another 30 began in December 2008. Participants transmitted daily symptom diaries using a BlackBerry. Alerts were triggered when symptom changes, missed diary transmissions, or medical care for a respiratory problem occurred. Participant encounters were initiated if COPD exacerbations were suspected. Participants used their BlackBerrys to report returns to normal breathing. Results Participants transmitted 99.9% of 28,514 possible daily diaries. All 191 (2.5/participant-year) COPD exacerbations meeting Anthonisen criteria were detected. During 148 of the 191 exacerbations (78%, 1.97/participant-year), patients were hospitalized and/or ordered prednisone, an antibiotic, or both. Respiratory viruses were detected in 78 of the 191 exacerbations (41%). Those coinciding with a respiratory viral infection averaged 12.0 days, and those without averaged 8.9 days (P < .04), with no difference in Anthonisen score. Respiratory symptom scores before exacerbations and after normal breathing return showed no differences. Exacerbations were more frequent during the Christmas period than the rest of the year but were not more frequent than in the rest of winter alone. Conclusions Smartphone-based collection of COPD symptom diaries enables near-complete identification of exacerbations at inception. Exacerbation rates in the Christmas season do not reach levels that necessitate changes in disease management.