CPFT Practice Exam 2025 – Complete Test Prep Guide

Smoking has a significant negative impact on pulmonary function test results, primarily by decreasing lung capacity. This reduction occurs due to the damaging effects of smoke on lung tissue, leading to inflammation and a loss of elastic recoil. Over time, exposure to the harmful substances in tobacco smoke can result in chronic bronchitis, emphysema, and other obstructive lung diseases, which are reflected in decreased forced vital capacity (FVC) and other relevant measurements in pulmonary function tests.

As individuals who smoke tend to develop airway obstruction and reduced airflow, their FEV1 (forced expiratory volume in one second) levels would also typically decrease. However, it's important to note that the impact of smoking extends beyond just FEV1; it affects overall lung capacity and function. Thus, stating that smoking only affects FEV1 does not fully capture the extent of its detrimental effects on the lungs.