Variability and Correlation of Lung Clearance Index (LCI) in Cystic Fibrosis (CF)

Cystic Fibrosis (CF) is a life-shortening disease that affects the cells responsible for making mucus, sweat, and digestive fluids. In people without CF, these secretions help to keep the body’s internal tubes and ducts clear and functioning smoothly. However, in people with CF, a genetic mutation causes the normally thin and slippery secretions to become thick and sticky. This causes the secretions to clog passages in the body, especially in the lungs and pancreas, leading to serious health problems. While treatments for CF have improved over the years, researchers still need better ways to track how the disease is progressing and how well treatments are working.

One possible way to do this is by measuring Lung Clearence Index (LCI). LCI is a number that tells us how evenly air is being distributed in the lungs. LCI is derived from the Multiple Breath Washout (MBW) technique. MBW is a lung function test that measures how quickly the lungs clear an inert tracer gas (like nitrogen). It may be more sensitive than other lung tests, especially in early stages of the disease, but more information is needed before it can be widely used in clinical trials or patient care.

The goal of this research is to better understand how LCI changes over time in adults with CF who are not experiencing a flare-up or major symptoms. We also want to find out how much variation there is in LCI results from one person to another, and whether LCI is linked to other commonly used CF measurements. In addition, we will look at how often LCI results are missing or unusable, which will help us decide whether this test is practical to use in larger studies.

To carry out this research, we will collect and analyze existing LCI data from adults with CF who are considered clinically stable. We will use a method called retrospective analysis, which means we will look back at information that has already been gathered. By studying these data, we aim to learn whether LCI is a reliable and useful tool for monitoring lung health in people with CF.