Prevalence of Chronic Airway Obstruction in Subjects With a History of Cigarette Smoking in a Primary Care Setting
Condition: Pulmonary Disease, Chronic Obstructive
MeSH terms: Lung Diseases; Pulmonary Disease, Chronic Obstructive
Study type: Observational

Summary: 
      This is a cross-sectional study to determine the prevalence of symptomatic airway obstruction
      using the LFQ as a screening tool in primary care patients with a history of cigarette
      smoking and to provide descriptive data of this patient population. The study design is
      multicenter, cross-sectional, and involves a single visit. This study is not intended to
      evaluate the efficacy or safety of any investigational products. Following completion of
      written informed consent, eligible study subjects will complete a single study visit
      encompassing all required study assessments. Study subjects will not receive blinded study
      medication for evaluations of efficacy and safety.

      All eligible patients will complete a self-administered Web survey that will include the LFQ.
      To meet both the primary and secondary aims, all patients with LFQ ≤ 18 (current cut-off for
      obstruction), as well as 5% of patients who score > 18, will be candidates for spirometric
      assessment. Only this subset of patients will undergo pulmonary function tests. Albuterol
      will be self-administered for determination of post-bronchodilator forced expiratory volume
      in one-second (FEV1)/forced vital capacity (FVC) ratio and post-bronchodilator FEV1
      percentage of predicted normal. The study will end when 800 patients have been assessed
      spirometrically or 3,000 patients have completed the LFQ (whichever criterion is achieved
      first).

      Prior to implementation of the full study, a pilot study will be conducted at two of the
      chosen study sites to pretest the proposed study procedures.
    

Detailed description: 
      The incidence of COPD is increasing throughout the world, with the vast majority of patients
      with the disease remaining undiagnosed (Coultas et al., 2001) and underreported (Frank et
      al., 2006; Global Initiative for Chronic Obstructive Lung Disease [GOLD], 2003; Peña et al.,
      2000; Takahashi et al., 2003; Van Weel et al., 2002). This is highlighted in a recent study
      that found 63% of patients with a smoking history and spirometry-confirmed COPD had no
      mention of COPD in their medical records (Frank et al., 2006). These findings are indicative
      of a low awareness of the condition among patients with COPD (Stratelis et al., 2004).

      The use of patient-completed questionnaires to assess smoking history and status, respiratory
      symptoms, and socioeconomic status is a reliable and valid method of screening for COPD
      diagnosis and severity (Bednarek et al., 2008). The range of conditions described as COPD has
      led to confusion about disease terminology and difficulty with diagnosis and communication,
      particularly in primary care (Fukuhara et al., 2005; Kesten and Chapman, 1993). Considering
      that approximately 80% of patients diagnosed with COPD are current and previous cigarette
      smokers, mass screening of these populations using office-based spirometry becomes an
      attractive option (Furguson et al., 2000). A questionnaire designed to capture patient
      answers specific to their disease condition could provide invaluable information, which, if
      it correlates adequately with spirometry, could markedly improve diagnosis and provide
      avenues for appropriate treatment decisions. There are data supporting the argument that the
      prevalence of physician-diagnosed COPD is much lower than the prevalence suggested by results
      of population-based spirometric surveys (Chapman, 2004; Fukuchi et al., 2004; Peña et al.,
      2000; Soriano et al., 2000). Evidently, the development of a practical and reliable tool
      could help bridge the gaps in diagnosis and disease awareness. Moreover, prevalence studies
      underscore the need to improve awareness of COPD among cigarette-smoking populations and to
      provide information that could potentially lead patients to seek treatment. Hence, there is a
      need to develop a screening questionnaire able to identify patients at risk of airflow
      obstruction, for further evaluation. The LFQ, developed for this purpose, consists of a
      series of questions pertaining to COPD risk factors and symptoms.

      Specifically, this study will aim to identify patients at risk of airflow obstruction as
      identified by the LFQ, the results of which will be followed for confirmation through
      subsequent spirometry in a subset of subjects. The LFQ will be evaluated against the
      spirometry results comparatively. A minimum age limit of 30 years is selected for subject
      participation in this study for further validation of the LFQ and to ascertain the enrollment
      of an adequately representative subset of subjects who may be bronchitic or asymptomatic for
      COPD, for comparison purposes with subjects with COPD. The study of this subject population
      may increase the sensitivity of COPD diagnosis and potentially provide information that could
      improve disease awareness and, as a consequence, possibly lead to optimization of disease
      management in primary care.

      This is a cross-sectional study to determine the prevalence of symptomatic airway obstruction
      using the LFQ as a screening tool in primary care patients with a history of cigarette
      smoking and to provide descriptive data of this patient population. The study design is
      multicenter, cross-sectional, and involves a single visit. This study is not intended to
      evaluate the efficacy or safety of any investigational products. Following completion of
      written informed consent, eligible study subjects will complete a single study visit
      encompassing all required study assessments. Study subjects will not receive blinded study
      medication for evaluations of efficacy and safety.

      All eligible patients will complete a self-administered Web survey that will include the LFQ.
      To meet both the primary and secondary aims, all patients with LFQ ≤ 18 (current cut-off for
      obstruction), as well as 5% of patients who score > 18, will be candidates for spirometric
      assessment. Only this subset of patients will undergo pulmonary function tests. Albuterol
      will be self-administered for determination of post-bronchodilator forced expiratory volume
      in one-second (FEV1)/forced vital capacity (FVC) ratio and post-bronchodilator FEV1
      percentage of predicted normal. The study will end when 800 patients have been assessed
      spirometrically or 3,000 patients have completed the LFQ (whichever criterion is achieved
      first).

      Prior to implementation of the full study, a pilot study will be conducted at two of the
      chosen study sites to pretest the proposed study procedures.
    

Intervention name(s): Non-Interventional
Intervention type(s): Other
Intervention description(s): Non-Investigational Product (Survey Study)
Time perspective: Cross-Sectional
Sampling method: Probability Sample
Study population: 
        Current or previous cigarette smokers of at least 30 years of age with a history of
        cigarette smoking of ≥ 10 pack-years, recruited from primary care centers.
      
Keywords: Spirometry; Bronchitis; COPD; Chronic Obstructive Pulmonary Disease (COPD); Emphysema; Chronic Bronchitis