Quality of spirometry and related diagnosis in primary care with a focus on clinical use.

American and European societies' (ATS/ERS) criteria for spirometry are often not met in primary care. Yet, it is unknown if quality is sufficient for daily clinical use. We evaluated quality of spirometry in primary care based on clinical usefulness, meeting ATS/ERS criteria and agreement on diagnosis between general practitioners (GPs) and pulmonologists. GPs included ten consecutive spirometry tests and detailed history questionnaires of patients who underwent spirometry as part of usual care. GPs and two pulmonologists assessed the spirometry tests and questionnaires on clinical usefulness and formulated a diagnosis. In total, 149 participants covering 15 GPs were included. Low agreements were found on diagnosis between GPs and pulmonologists 1 (κ = 0.39) and 2 (κ = 0.44). GPs and pulmonologists rated >88% of the tests as clinically useful, although 13% met ATS/ERS criteria. This real-life study demonstrated that clinical usefulness of routine primary care spirometry tests was high, although agreement on diagnosis was low.

A method to study the effect of bronchodilators on smoke retention in COPD patients: study protocol for a randomized controlled trial.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a common disease, associated with cardiovascular disease. Many patients use (long-acting) bronchodilators, whilst they continue smoking alongside. We hypothesised an interaction between bronchodilators and smoking that enhances smoke exposure, and hence cardiovascular disease. In this paper, we report our study protocol that explores the fundamental interaction, i.e. smoke retention. METHOD: The design consists of a double-blinded, placebo-controlled, randomised crossover trial, in which 40 COPD patients smoke cigarettes during both undilated and maximal bronchodilated conditions. Our primary outcome is the retention of cigarette smoke, expressed as tar and nicotine weight. The inhaled tar weights are calculated from the correlated extracted nicotine weights in cigarette filters, whereas the exhaled weights are collected on Cambridge filters. We established the inhaled weight calculations by a pilot study, that included paired measurements from several smoking regimes. Our study protocol is approved by the local accredited medical review ethics committee. DISCUSSION: Our study is currently in progress. The pilot study revealed valid equations for inhaled tar and nicotine, with an R2 of 0.82 and 0.74 (p < 0.01), respectively. We developed a method to study pulmonary smoke retentions in COPD patients under the influence of bronchodilation which may affect smoking-related disease. This trial will provide fundamental knowledge about the (cardiovascular) safety of bronchodilators in patients with COPD who persist in their habit of cigarette smoking. TRIAL REGISTRATION: ClinicalTrials.gov: NCT00981851.

Interaction in COPD experiment (ICE): a hazardous combination of cigarette smoking and bronchodilation in chronic obstructive pulmonary disease.

Chronic obstructive pulmonary disease (COPD) is a highly prevalent disease, characterised by poorly reversible, obstructive airflow limitation. Alongside other comorbidities, COPD is associated with increased morbidity and mortality resulting from cardiovascular disease - mainly heart failure and ischemic heart disease. Both diseases share an important risk factor, namely, smoking. About 50% of COPD patients are active cigarette smokers. Bronchodilation is the cornerstone of pharmaceutical treatment for COPD symptoms, and half of all COPD patients use long-acting bronchodilating agents. Discussion about these agents is currently focusing on the association with overall mortality and morbidity in COPD patients, of cardiovascular origin in particular. Bronchodilation diminishes the hyperinflated state of the lung and facilitates the pulmonary deposition of cigarette smoke by deeper inhalation into the smaller airways. Smaller particles, as in smoke, tend to penetrate and depose more in these small airways. In addition, bronchodilation indeed increases carbon monoxide uptake in the lungs, an important gaseous compound of cigarette smoke. Since the number of cigarettes smoked is positively correlated to mortality from cardiac events, we therefore hypothesise that chronic bronchodilation increases cardiovascular disease and mortality in COPD patients who continue smoking by increasing pulmonary retention of pathogenic smoke constituents. Indeed, a recent meta-analysis is suggestive that long-acting anticholinergics might increase cardiovascular disease if patients exceed a certain number of cigarettes smoked. To demonstrate the fundamental mechanism of this pathogenic interaction we will perform a randomised placebo-controlled cross-over trial to investigate the effect of maximum bronchodilation on the retention of cigarette smoke constituents. In 40 moderate to severe COPD patients we measure the inhaled and exhaled amount of tar and nicotine, as well during maximum bronchodilation as during administration of placebo. The fraction of retention of tar and nicotine is subsequently calculated for both circumstances and analysed for association with bronchodilation. Further observational cohort studies or randomised clinical trials designed to monitor cardiovascular events may well evaluate the interaction. Since many patients are at risk for this possibly hazardous interaction, its relevance to our society and healthcare is potentially great. The implication will be that the urgency to quit smoking is intensified. Besides, chronic bronchodilation - specifically long-acting bronchodilators - needs to be discouraged in smoking COPD patients that refuse to quit.

Current clinical guideline definitions of airflow obstruction and COPD overdiagnosis in primary care.

The aim of the present study was to establish the agreement between two recommended definitions of airflow obstruction in symptomatic adults referred for spirometry by their general practitioner, and investigate how rates of airflow obstruction change when pre-bronchodilator instead of post-bronchodilator spirometry is performed. The diagnostic spirometric results of 14,056 adults with respiratory obstruction were analysed. Differences in interpretation between a fixed 0.70 forced expiratory volume in one second (FEV(1))/forced vital capacity (FVC) cut-off point and a sex- and age-specific lower limit of normal cut-off point for this ratio were investigated. Of the subjects, 53% were female and 69% were current or ex-smokers. The mean post-bronchodilator FEV(1)/FVC was 0.73 in males and 0.78 in females. The sensitivity of the fixed relative to the lower limit of normal cut-off point definition was 97.9%, with a specificity of 91.2%, positive predictive value of 72.0% and negative predictive value of 99.5%. For the subgroup of current or ex-smokers aged > or =50 yrs, these values were 100, 82.0, 69.2 and 100%, respectively. The proportion of false positive diagnoses using the fixed cut-off point increased with age. The positive predictive value of pre-bronchodilator airflow obstruction was 74.7% among current or ex-smokers aged > or =50 yrs. The current clinical guideline-recommended fixed 0.70 forced expiratory volume in one second/forced vital capacity cut-off point leads to substantial overdiagnosis of obstruction in middle-aged and elderly patients in primary care. Using pre-bronchodilator spirometry leads to a high rate of false positive interpretations of obstruction in primary care.

[Prevalence of and health care consumption for asthma and COPD in relation to ethnicity]. / Prevalentie en zorgconsumptie bij astma en COPD in relatie tot etniciteit.

OBJECTIVE: To determine whether there are differences in prevalence of and health care consumption for asthma and COPD between Dutch people of Turkish, Moroccan and Surinamese origin and indigenous Dutch people. DESIGN: Retrospective. METHOD: Based on data from the 'Second Dutch national study into morbidity and interventions in general practice', we compared the prevalence of asthma and COPD in the different ethnic groups. In addition, we compared the use of various airway medications and the number of general practice contacts between these ethnic groups. RESULTS: We analysed data of 240,067 indigenous Dutch, 2,942 Turkish, 2,416 Moroccan and 3,320 Surinamese subjects. Asthma is more prevalent among Surinamese and seems less prevalent among Moroccans. COPD seems less prevalent among immigrants than among the indigenous Dutch population. Immigrants tend to have less prescriptions of prophylactic maintenance airway medication and they also tend to have less airway-related general practice contacts than indigenous Dutch patients. CONCLUSION: Differences exist in the prevalence of and health care consumption for asthma and COPD between the different ethnic groups in the Netherlands. There seems to be underdiagnosis of COPD in immigrants. Moreover, immigrant asthma and COPD patients are probably undertreated.

Impact of a spirometry expert system on general practitioners' decision making.

The present study assessed the impact of computerised spirometry interpretation expert support on the diagnostic achievements of general practitioners (GPs), and on GPs' decision making in diagnosing chronic respiratory disease. A cluster-randomised controlled trial was performed in 78 GPs who each completed 10 standardised paper case descriptions. Intervention consisted of support for GPs' spirometry interpretation either by an expert system (expert support group) or by sham information (control group). Agreement of GPs' diagnoses was compared with an expert panel judgement, which served as the primary outcome. Secondary outcomes were: additional diagnostic test rates; width of differential diagnosis; certainty of diagnosis; estimated severity of disease; referral rate; and medication or nonmedication changes. Effects were expressed as odds ratios (ORs) with 95% confidence intervals (CIs). There were no differences between the expert support and control groups in the agreement between GPs and expert panel diagnosis of chronic obstructive pulmonary disease (OR (95% CI) 1.08 (0.70-1.66)), asthma (1.13 (0.70-1.80)), and absence of respiratory disease (1.32 (0.61-2.86)). A higher rate of additional diagnostic tests was observed in the expert support group (2.5 (1.17-5.35)). Computerised spirometry expert support had no detectable benefit on general practitioners' diagnostic achievements and the decision-making process when diagnosing chronic respiratory disease.

Lower inhaled steroid requirement with a fluticasone/salmeterol combination in family practice patients with asthma or COPD.

BACKGROUND: Previous studies on inhaled steroid and long-acting beta2-agonist combination products may not be representative for the asthma and chronic obstructive pulmonary disease (COPD) patients in family practice. OBJECTIVES: To compare in a group of doctor-diagnosed patients with asthma or COPD, the effects of a lower dose of fluticasone in a combination product with salmeterol with conventional treatment (i.e. a higher dose of fluticasone), both supplemented with as-needed use of a short-acting bronchodilator. METHODS: The study was a 12-week multicentre, randomized controlled, double-blind trial. In all, 41 family practices recruited 137 patients diagnosed with asthma and 40 patients diagnosed with COPD. Primary outcome was the forced expiratory volume in 1 second (FEV1) as percentage of predicted. Morning peak expiratory flow (PEF), symptom-free days, health status [Asthma Quality of Life Questionnaire (AQLQ) and St. George's Respiratory Questionnaire (SGRQ)], exacerbations, use of short-acting bronchodilators and adverse events were secondary outcomes. RESULTS: FEV1% predicted increased 2.6% (SD 8.3) in fluticasone/salmeterol- and 0.01% (SD 6.6) in fluticasone-treated patients (overall: P=0.036, asthma: P=0.025 and COPD: P=0.700). PEF increased in favour of fluticasone/salmeterol in asthma patients only (P=0.016). Fluticasone/salmeterol-treated asthma patients had 1.1 more symptom-free days per week (P=0.044); no such effect was observed for COPD (P=0.769). There were no differences in total AQLQ and SGRQ scores, exacerbations, use of reliever puffs or adverse effects. CONCLUSIONS: In family practice patients diagnosed with asthma, several treatment goals were better achieved with a lower dose of fluticasone and salmeterol in a combination product than with a higher dose of fluticasone. We found no differences between the two approaches for patients with COPD.