Detection of COPD in a high risk population:Should the diagnostic work-up include bronchodilator reversibility testing?

BACKGROUND: Underdiagnosis of chronic obstructive pulmonary disease (COPD) is widespread. Early detection of COPD may improve the outcome by timely smoking cessation, a change in lifestyle, and treatment with an inhaled bronchodilator (BD). The objective of this study was to evaluate the diagnostic role of BD reversibility testing in early COPD case finding. METHODS: General practitioners (n=241) consecutively recruited subjects aged ≥35 years with relevant exposure (history of smoking, and/or occupational exposure) and at least one respiratory symptom. Information on age, smoking status, body mass index, dyspnea score (Medical Research Council scale), and spirometry was obtained. Individuals with airway obstruction (forced expiratory volume in one second [FEV(1)]/forced vital capacity [FVC] <0.70) underwent a BD test with an inhaled β(2) agonist, which was considered positive if ΔFEV(1) was >0.20 L and >12%. Asthma and COPD were, respectively, defined as an FEV(1) increase >0.50 L and a post-BD FEV(1)/FVC <0.70. RESULTS: In total, 4,049 subjects (51% male) were included (mean age 58 years, body mass index 27, 32 pack-years of smoking). A significant BD response was found in 143 (15%) of the 937 subjects (23%) with airway obstruction at screening spirometry. In 59% of these subjects, the post-BD FEV(1)/FVC remained <0.70. In 24% of the subjects with pre-BD airway obstruction, the post-BD FEV(1)/FVC ratio was within the reference range. In subjects with confirmed COPD, the mean increase in FEV(1) following BD was 0.11 L±0.10 L. The subjects with COPD and a significant BD response were characterized by a higher prevalence of dyspnea (72% versus 57%, P=0.02) but less cough (55% versus 75%, P=0.001) when compared with COPD subjects without BD reversibility. CONCLUSION: Administration of a BD in COPD case finding is important in order to determine the post-BD FEV(1)/FVC ratio. Exclusion of subjects with a significant BD response may result in underdiagnosis of COPD, and we question the need for the BD reversibility test in the diagnostic screening algorithm in early COPD case finding

Assessment of fitness for recreational scuba diving in candidates with asthma:a pilot study

BackgroundAsthma may be regarded as a contraindication to scuba diving.PurposeA clinical algorithm to assess fitness to dive among individuals with asthma was developed and tested prospectively in clinical practice.Study designCohort study.MethodsAll patients with possible asthma referred to Hvidovre Hospital, Denmark, for assessment of fitness to dive over a 5-year period (2013–2017) were included. Fitness to dive was assessed by case history, spirometry and mannitol challenge test. All patients with ≥10% decline in forced expiratory volume in 1 s (FEV1) (at any point during the challenge test) were offered step-up asthma therapy and rechallenge after at least 3 months. Patients with &lt;10% decline in FEV1 after administration of a maximum dose of mannitol at the latest challenge were classified as having no medical contraindications to scuba diving.ResultsThe study cohort comprised 41 patients (24 men; mean age 33 years), of whom 71% and 63% of men and women, respectively, were treated with rescue bronchodilator and inhaled corticosteroid. After the first mannitol challenge test, 21 patients were classified as having no medical contraindications to scuba diving, of whom 16 were currently prescribed asthma medication. After step-up asthma therapy and rechallenge test, an additional seven patients were classified as having no medical contraindications to scuba diving. Overall, using this clinical algorithm, 28 (68%) of the referred patients were finally assessed as having no medical contraindications to scuba diving.ConclusionUsing a clinical algorithm with mannitol challenge to assess fitness to dive among patients with possible asthma and allowing a rechallenge test after step-up asthma therapy increased the proportion of individuals classified as having no medical contraindications to scuba diving. However, as this algorithm has so far not been evaluated against actual scuba diving safety, further studies are clearly needed before it can be implemented with confidence for use in clinical practice.Clinical relevanceAn algorithm to assess fitness for scuba diving among individuals with possible asthma using bronchial challenge test, with the option of step-up asthma therapy and rechallenge for reassessment, has been developed for clinical use

Incidence and long-term outcome of severe asthma-COPD overlap compared to asthma and COPD alone:a 35-year prospective study of 57,053 middle-aged adults

BACKGROUND: Incidence and prognosis for severe asthma–COPD overlap is poorly characterized. We investigated incidence and long-term outcome for patients with asthma–COPD overlap compared to asthma and COPD alone. MATERIALS AND METHODS: A total of 57,053 adults (aged 50–64 years) enrolled in the Danish Diet, Cancer, and Health cohort (1993–1997) were followed in the National Patients Registry for admissions for asthma (DJ45–46) and COPD (DJ40–44) and vital status. Asthma–COPD overlap was defined as at least one hospital admission for asthma and one for COPD (different time points), and incident asthma–COPD overlap as at least one of the diagnoses occurring after enrollment into the Diet, Cancer, and Health cohort. RESULTS: A total of 1,845 (3.2%) and 4,037 (7.1%) participants had admissions for asthma and COPD, respectively, with 662 (1.2%) participants with asthma–COPD overlap. Incidence rate of asthma–COPD overlap per 1,000 person-years was higher in women (0.73) than in men (0.54) (P<0.02). Mortality rate was higher in asthma–COPD overlap (25.9 per 1,000 person-years) compared with COPD (23.1, P<0.05) and asthma (7.9, P<0.001) alone. Compared to COPD alone, mortality was higher in women with asthma–COPD overlap (19.6 and 25.5, respectively; P<0.01), and the excess mortality rate for asthma–COPD overlap patients was most prominent for younger age groups (12.9 compared to 7.2 and 4.6 for COPD and asthma alone, respectively; P<0.01). CONCLUSION: This large population-based study revealed a higher incidence of severe asthma–COPD overlap in women compared to men, and furthermore that all-cause mortality is higher in women and younger subjects with asthma–COPD overlap compared with those with asthma or COPD alone

Identifying possible asthma-COPD overlap syndrome in patients with a new diagnosis of COPD in primary care

The asthma–chronic obstructive pulmonary disease (COPD) overlap syndrome (ACOS) remains poorly characterised. Our aim was to describe an algorithm for identifying possible ACOS in adults with newly diagnosed COPD in primary care. General practitioners (n=241) consecutively recruited subjects ⩾35 years, with tobacco exposure, at least one respiratory symptom and no previous diagnosis of obstructive lung disease. Possible ACOS was defined as chronic airflow obstruction, i.e., post-bronchodilator (BD) forced expiratory volume 1/forced vital capacity (FEV(1)/FVC) ratio<0.70, combined with wheeze (ACOS wheeze) and/or significant BD reversibility (ACOS BD reversibility). Of 3,875 (50% females, mean age 57 years) subjects screened, 700 (18.1%) were diagnosed with COPD, i.e., symptom(s), tobacco exposure and chronic airflow obstruction. Indications for ACOS were found in 264 (38%) of the COPD patients. The prevalence of ACOS wheeze and ACOS BD reversibility was 27% (n=190) and 16% (n=113), respectively (P<0.001), and only 6% (n=39) of the COPD patients fulfilled both criteria for ACOS. Patients with any ACOS were younger (P=0.04), had more dyspnoea (P<0.001), lower FEV(1)%pred (67% vs. 74%; P<0.001) and lower FEV(1)/FVC ratio (P=0.001) compared with COPD-only patients. Comparing subjects fulfilling both criteria for ACOS with those fulfilling criteria for ACOS wheeze only (n=151) and those fulfilling criteria for ACOS BD reversibility only (n=74) revealed no significant differences. Irrespective of the applied ACOS definition, no significant difference in life-time tobacco exposure was found between ACOS- and COPD-only patients. In subjects with a new diagnosis of COPD, the prevalence of ACOS is high. When screening for COPD in general practice among patients with no previous diagnosis of obstructive lung disease, patients with possible ACOS may be identified by self-reported wheeze and/or BD reversibility

Diagnostic work-up in patients with possible asthma referred to a university hospital

OBJECTIVE: The best strategy for diagnosing asthma remains unclear. Accordingly, the aim of this study was to evaluate diagnostic strategies in individuals with possible asthma referred to a respiratory outpatient clinic at a university hospital. METHODS: All individuals with symptoms suggestive of asthma referred over 12 months underwent spirometry, bronchodilator reversibility test, Peak expiratory flow rate (PEF) registration, and bronchial challenge test with methacholine and mannitol on three separate days. The results of these tests were compared against an asthma diagnosis based on symptoms, presence of atopy and baseline spirometry made by a panel of three independent respiratory specialists. RESULTS: Of the 190 individuals examined, 63% (n=122) were classified as having asthma. Reversibility to β(2)-agonist had the lowest sensitivity of 13%, whereas airway hyperresponsiveness to methacholine had the highest (69%). In contrast, specificity was the highest for reversibility testing (93%), whereas methacholine had the lowest specificity (57%). The combination of reversibility, peak-flow variability, and methacholine yielded a cumulative sensitivity of 78%, albeit a specificity of 41%. In comparison, a combination of reversibility and mannitol resulted in a specificity of 82% and a sensitivity of 42%. CONCLUSION: In this real-life population, different diagnostic test combinations were required to achieve a high specificity for diagnosing asthma and a high sensitivity, respectively: Our findings suggest that the diagnostic test approach should be based on whether the aim is to exclude asthma (high sensitivity required) or confirm a diagnosis of asthma (high specificity required)