What does significant variability in pulmonary function test results suggest about a patient's condition?

Significant variability in pulmonary function test results is indicative of conditions that affect airway responsiveness and can lead to fluctuating levels of airflow obstruction. This is particularly characteristic of disorders like asthma, where patients may experience significant changes in their lung function due to various factors such as allergens, exercise, or respiratory infections. In poorly controlled chronic obstructive pulmonary disease (COPD), variability can also be present, often related to exacerbations or changes in physical condition.

Variability suggests that the lung function is not stable and may respond to environmental or physiological triggers, highlighting the importance of monitoring the condition and adapting treatment accordingly for optimal management.