Prevalence of COPD among symptomatic patients in a primary care setting

Abstract

Objective:

Spirometry is recognized as the gold standard assessment for the diagnosis of COPD. However, spirometry continues to be underused, perpetuating the underdiagnosis of COPD. The aim of this study was to evaluate the prevalence of COPD in a primary care setting in patients with a smoking history and self-reported chronic bronchitis symptoms.

Research design and methods:

This was a multi-center, cross-sectional study. The primary assessment was the percentage of patients with airway obstruction (post-bronchodilator FEV₁/FVC ratio ≤ 0.70) compared to those without obstruction (post-bronchodilator FEV₁/FVC ratio > 0.70).

Results:

Airflow obstruction consistent with COPD was confirmed in 26% of patients (mean age 52.9 years, FEV₁ 81.4% predicted and smoking history 39.8 pack-years) that reported chronic bronchitis symptoms. Airflow obstruction increased with age and smoking history. Slight or moderate dyspnea was reported by 68% of patients and the majority had not talked to their doctor about cough and continued to smoke.

Limitations:

Patients were evaluated at a single visit. The definition of airway obstruction used may have lead to overdiagnosis in patients aged 70 and older.

Conclusion:

This study confirms that many patients with COPD remain undiagnosed in the primary care setting. Evaluation of spirometry in patients with a smoking history and chronic bronchitis symptoms can aid in the diagnosis of COPD, allowing earlier treatment thereby reducing the burden of this debilitating disease.

Clinical trial registration:

Study code ADC109043; clinicaltrials.gov #NCT00442468.

Key words: :

• Airflow obstruction
• Chronic bronchitis
• COPD
• Primary care

Transparency

Declaration of funding

This study was funded by GlaxoSmithKline, Research Triangle Park, NC, USA.

Declaration of financial/other relationships

B.Y. has disclosed that she has received research grants from GSK, Novartis and BI/Pfizer in the area of COPD screening, and has served on the advisory committee for COPD related studies of GSK and BI-Pfizer. D.M. has disclosed that he has received research funding from GSK, Novartis and Pfizer, and has served as a speaker or consultant for GSK, Novartis, Pfizer, Astra-Zeneca, Dey and Sepracor. T.L. disclosed that he has no conflicts of interest. G.R. has disclosed that he is on the speakers’ bureau and advisory boards for GSK and Cephalon, and that his corporation has received research grant support from GSK, Cephalon, Sepacor, Novartis, Wyeth, Sanyko, Forrest, Takada, Orthomcneil and Capnia. G.C., I.R. and A.E. have disclosed that they are GSK employees, and G.C. and A.E. own stock in the company.

Some peer reviewers receive honoraria from CMRO for their review work. The peer reviewers of this paper have disclosed that they have no relevant financial relationships.

Acknowledgment

The authors acknowledge the editorial assistance of Tracy Fischer in the development and author review of this manuscript.

These data were presented in part at the 2008 Chest Annual Meeting in Philadelphia, PA, USA and at the 2009 American Thoracic Society Meeting in San Diego, CA, USA.