The use and abuse of office spirometry

Area of Science:

• Pulmonary Medicine
• General Practice
• Diagnostic Testing

Background:

• Spirometry is underutilized by General Practitioners (GPs) for diagnosing Chronic Obstructive Pulmonary Disease (COPD).
• Inhaler prescriptions for COPD are common but may be inappropriate without confirmed severe airway obstruction, leading to unnecessary costs and side effects.
• The diagnostic yield of general population spirometry for COPD is low, with high false positive rates.

Purpose of the Study:

• To evaluate the justification of population-wide spirometry programs for COPD detection outside primary care.
• To highlight the importance of accurate spirometry in guiding COPD management and inhaler prescription by GPs.
• To assess the feasibility and impact of improving spirometry quality in primary care settings.

Main Methods:

• Review of spirometry programs and their effectiveness in detecting COPD.
• Analysis of the true positive and false positive rates of spirometry in the general adult population.
• Examination of GP prescribing habits for COPD inhalers in relation to spirometry use.

Main Results:

• Population-wide spirometry programs for COPD detection are not cost-effective due to low true positive yields and high false positive rates.
• GPs frequently prescribe inhalers without spirometry confirmation, indicating underutilization of the test.
• Finnish studies demonstrate that GPs can achieve good quality spirometry, suggesting potential for improved diagnostic accuracy.

Conclusions:

• Screening spirometry for COPD in the general adult population is not recommended.
• Confirming severe airway obstruction via spirometry is crucial before prescribing COPD inhalers to current or former smokers.
• Referral for pre- and post-bronchodilator spirometry is advised when high-quality testing is unavailable in primary care; further research is needed on systematic use of results for patient benefit.