In the development of new drugs for severe asthma, it is a challenge from an ethical point of view to randomize severe asthma patients to placebo, and to obtain long-term safety data due to discontinuations. The aim of this study was to evaluate the feasibility of using electronic health record (EHR) data to create a real-world reference population of uncontrolled asthmatic patients to supplement the concurrent control/placebo group in long-term studies of asthma.
EHR data from 36 primary care centres and a University hospital in Sweden were linked to Swedish mandatory health registers (2005-2013), creating a population covering 33 890 asthma patients, including data on co-morbidities, risk factors and laboratory/respiratory measurements. A severe asthma EHR reference cohort was established. We used logistic regression to estimate the propensity score (probability) of each RCT or EHR patient existing in the EHR cohort given their covariates.
We created an EHR-derived reference cohort of 240 patients, matching the placebo group (N?=?151) in an RCT of severe asthma. The exacerbation rate during follow-up in the EHR study population was 1.24 (weighted) compared to 0.9 in the RCT placebo group. Patients in the EHR cohort were of similar age as in the RCT placebo group, 50.6 years versus 50.1 years; had slightly higher body mass index 27.0 kg/m2 versus 27.3 kg/m2; and consisted of 40% versus 34% males.
The results indicate that EHRs provide an opportunity to supplement the control group in RCTs of severe diseases.
The purpose was to examine bronchial asthma according to cumulative exposure to fume particulates conferred by stainless steel and mild steel welding through a proxy of redeemed prescribed asthma pharmaceuticals.
A Danish national company-based historical cohort of 5,303 male ever-welders was followed from 1995 to 2011 in the Danish Medicinal Product Registry to identify the first-time redemption of asthma pharmaceuticals including beta-2-adrenoreceptor agonists, adrenergic drugs for obstructive airway diseases and inhalable glucocorticoids. Lifetime exposure to welding fume particulates was estimated by combining questionnaire data on welding work with a welding exposure matrix. The estimated exposure accounted for calendar time, welding intermittence, type of steel, welding methods, local exhaustion and welding in confined spaces. Hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated using a Cox proportional hazards model adjusting for potential confounders and taking modifying effects of smoking into account.
The average incidence of redemption of asthma pharmaceuticals in the cohort was 16 per 1,000 person year (95% CI 10-23 per 1,000 person year). A moderate nonsignificant increased rate of redemption of asthma medicine was observed among high-level exposed stainless steel welders in comparison with low-level exposed welders (HR 1.54, 95% CI 0.76-3.13). This risk increase was driven by an increase risk among non-smoking stainless steel welders (HR 1.46, 95% CI 1.06-2.02). Mild steel welding was not associated with increased risk of use asthma pharmaceuticals.
The present study indicates that long-term exposure to stainless steel welding is related to increased risk of asthma in non-smokers.
Telephone surveys describing suboptimal asthma control may be biased by low response rates. In order to obtain an unbiased assessment of asthma control and assess its impact in primary care, primary care physicians used a 1-page control questionnaire in 50 consecutive asthma patients. Of the 10,428 patients assessed by 354 physicians, 59% were uncontrolled, 19% well-controlled and 23% totally controlled. Physicians overestimated control, regarding only 42% of patients as uncontrolled. Physicians were more likely to report plans to alter the regimens of uncontrolled patients than controlled patients (1.29 versus 0.20 medication changes per patient) doing so in a fashion consistent with guideline recommendations. Of the uncontrolled patients, 59% required one or more urgent care or specialist visits versus 26 and 15% of well-controlled or totally controlled patients, respectively. Patients were more likely to report short-term symptom control when they had not required urgent or specialist care (odds ratio 5.68; 95% confidence interval 4.91-6.58). The majority of asthma patients treated in general practice are uncontrolled. Lack of control can be recognised by physicians who are likely to consider appropriate changes to therapy. A lack of short-term symptom control of asthma is associated with excess healthcare utilisation.
Comment In: Eur Respir J. 2008 Feb;31(2):229-3118238943
This study describes the utilization of anti-asthma medications in two groups of users of such medications in the province of Quebec, Canada, during the year from June 1, 1990, to May 31, 1991. It is based on a secondary analysis of existing data banks recording the medications reimbursed by two government-funded ambulatory drug reimbursement programs that cover individuals aged 65 and over (seniors) and income security (welfare) recipients (ISRs). The study analyzed the use of the anti-asthma medications included in the list of medications eligible for reimbursement for program beneficiaries. Use was studied in two random samples of individuals who had at least one prescription filled for an anti-asthma medication (2566 seniors and 3695 ISRs). The most commonly used medication in both groups was inhaled salbutamol 100 mcg. Various forms of theophylline tablets were also used by a high proportion of the sample studied. Over 75% of the seniors and 68% of the ISR group used at least one form of theophylline during the course of the year. Inhaled corticosteroids were used by 43% of the seniors and by 36% of the ISR group, and sympathomimetics (beta 2-agonists), by 63% of seniors and 68% of ISRs.
BACKGROUND: Objective assessment of airway function is important in epidemiologic studies of asthma to facilitate comparison between studies. Airway hyperresponsiveness (AHR), peak expiratory flow (PEF) variability, and bronchodilator reversibility (BR) are widely used as markers of airway lability in such studies. Data from a survey of a population sample of adolescents and young adults (n = 609; 288 males), aged 13-23 years, were analyzed to investigate whether AHR, PEF variability, and BR can be used interchangeably as markers of asthma in an epidemiological setting. METHODS: Case history, including self-reported and doctor-diagnosed asthma, smoking habits, and use of asthma medication, was obtained by interview and questionnaire. Lung function, airway responsiveness (positive test: PC20 FEV1 20%), BR (positive test: deltaFEV1 [(FEV1max - FEV1min)/FEV1max) 100] > 10%), blood eosinophil count, and skin prick test reactivity were measured by using standard techniques. RESULTS: The prevalence of a positive test was AHR 16.4%, PEFpos 13.3%, and BRpos 7.2%, respectively; 73.5% of the sample had three negative tests. Among the 74 participants with current self-reported asthma (12.2%), 34 subjects (46%) had more than one positive test. Using AHR as the only objective marker of asthma identified 93% of the participants with current asthma, whereas PEF and BR identified 45% and 10%, respectively. Confining the analysis to participants with only one positive test revealed that 61% of the subjects with isolated AHR had current asthma, whereas none of the subjects with isolated BRpos had asthma, and only one participant with isolated PEFpos had current asthma. Degree of histamine responsiveness was closer associated with other asthma-related factors, including self-reported asthma, use of asthma medication, and level of lung function, than PEF variability and bronchodilator responsiveness. CONCLUSIONS: Airway responsiveness to histamine, diurnal peak-flow variability, and bronchodilator reversibility cannot be used interchangeably as objective markers of asthma in epidemiologic studies. On the basis of the present findings, airway hyperresponsiveness to a nonspecific bronchoconstrictor is recommended as the objective marker of asthma-related airway lability.
To determine whether asthma control in Canada had improved since the last major survey in 1999 by exploring how well patients' asthma was controlled, how much they knew about asthma control, and how they used health care resources.
National telephone survey of patients between April and August 2004.
Eight hundred ninety-three adults 18 to 54 years old diagnosed with asthma more than 6 months before the survey.
Patients' control of their asthma, patients' knowledge about asthma, the frequency and duration of periods of worsening asthma, and patients' use of health care resources to manage those periods.
In total, 26,210 households listed in a consumer database were contacted. Excluding ineligible households and households with a language barrier, a member of 13% of the households completed the 35-minute survey. Based on definitions in Canadian guidelines, 53% of patients had symptomatic uncontrolled asthma. In the previous year, almost all asthma patients had experienced worsening of symptoms that lasted on average 13.6 days for patients with uncontrolled asthma and 8.0 days for patients with controlled asthma (P
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A recurring epidemic of asthma exacerbations in children occurs annually in September in North America when school resumes after summer vacation.
Our goal was to determine whether montelukast, added to usual asthma therapy, would reduce days with worse asthma symptoms and unscheduled physician visits of children during the September epidemic.
A total of 194 asthmatic children aged 2 to 14 years, stratified according to age group (2-5, 6-9, and 10-14 years) and gender, participated in a double-blind, randomized, placebo-controlled trial of the addition of montelukast to usual asthma therapy between September 1 and October 15, 2005.
Children randomly assigned to receive montelukast experienced a 53% reduction in days with worse asthma symptoms compared with placebo (3.9% vs 8.3%) and a 78% reduction in unscheduled physician visits for asthma (4 [montelukast] vs 18 [placebo] visits). The benefit of montelukast was seen both in those using and not using regular inhaled corticosteroids and among those reporting and not reporting colds during the trial. There were differences in efficacy according to age and gender. Boys aged 2 to 5 years showed greater benefit from montelukast (0.4% vs 8.8% days with worse asthma symptoms) than did older boys, whereas among girls the treatment effect was most evident in 10- to 14-year-olds (4.6% [montelukast] vs 17.0% [placebo]), with nonsignificant effects in younger girls.
Montelukast added to usual treatment reduced the risk of worsened asthma symptoms and unscheduled physician visits during the predictable annual September asthma epidemic. Treatment-effect differences observed between age and gender groups require additional investigation.
The current study aimed to assess the impact on patient health status during an acute exacerbation of chronic obstructive pulmonary disease (AECOPD). A total of 421 COPD patients were enrolled in a multicentre, single-arm study with a 6-month observational follow-up period. Patients received two inhalations of Symbicort 200 Turbuhaler(R) twice a day. Patients were assessed before the run-in period, at baseline and at 1, 3 and 6 months. Patients were instructed to report a change in respiratory symptoms lasting >24 h. This defined an AECOPD. In addition to the initial call, the St George's Respiratory Questionnaire (SGRQ), COPD Control Questionnaire (CCQ), Medical Research Council (MRC) dyspnoea scale and activities of daily living (ADL) were completed at 5-7 and 12-14 days. A group of 176 patients reported at least one AECOPD. Exacerbations were associated with statistically significant mean changes (worsening) in the SGRQ activity and impact domains at onset (mean +/- sd 12.1 +/- 18.1 and 14.0 +/- 15.2), during the first (9.8 +/- 19.0 and 9.4 +/- 16.6) and second weeks (3.1 +/- 15.5 and 3.3 +/- 14.7). Clinically significant deterioration in SGRQ impact scores was shown in 71% of patients following early identification, with 55 and 37% during the first and second weeks of an AECOPD, respectively. Acute exacerbation severely impacts on health status. The current study provides valuable information on the change in health status during an acute exacerbation of chronic obstructive pulmonary disease that can be utilised for future trials that evaluate therapeutic intervention.
In the year 1990 the European Community Respiratory Health Survey I (ECRHS I) demonstrated that the prevalence of these diseases was lowest in Iceland (www.ecrhs.org). In order to compare the prevalence of respiratory symptoms in Reykjavik over time, a new identical cross-sectional study was performed seventeen years later.
Both cohorts, were in the age group 20-44 years and randomly selected from the population in Reykjavik and suburbs. Both answered questionnaires about respiratory symptoms, nasal allergy and use of anti-asthmatic drugs. The second cohort was part of the EuroPrevall study (www.europrevall.org) performed in 2007.
Response rate was lower in 2007 (999 or 43.2%) than in 1990 (2.903 or 80.6%).The prevalence of attacks of asthma increased over time from 2.2% to 6.7% (p