A pulmonary function test (PFT) is a group of breathing tests that measure how well the lungs move air in and out and transfer oxygen into the blood. Common components include spirometry, lung volume measurement, and diffusion capacity (DLCO). PFTs help diagnose and monitor conditions such as asthma, COPD, restrictive lung disease, and pulmonary fibrosis. Results are expressed as absolute values and percentages of predicted norms based on age, gender, height, and ethnicity. For life insurance underwriting, PFTs provide objective data on lung function that helps quantify the severity of respiratory disease and the associated mortality risk.

Underwriters use pulmonary function test reports when evaluating applicants with respiratory diagnoses or symptoms. They look at FEV1, FVC, FEV1/FVC ratio, and DLCO, comparing them to predicted values and noting any bronchodilator response. Better-than-expected PFTs can support more favorable offers, while severely reduced or worsening values often lead to ratings or declines. Advisors working with clients who have lung conditions can expedite underwriting by collecting recent PFT results and pulmonologist notes. Educating clients that well-controlled disease and stable PFTs may improve insurability encourages adherence to treatment and follow-up care.