Treating Rare Lung Disease With Statins

Cholesterol-lowering statins may offer hope as a noninvasive treatment of a rare lung disease called autoimmune pulmonary alveolar proteinosis, according to a study published in Nature Communications.

The syndrome is caused by improperly functioning alveolar macrophage cells in the lungs, which leads to a buildup of an oily substance consisting of cholesterol, phospholipid, and proteins. When the alveoli, or air sacs, become clogged, patients experience shortness or breath and the threat of respiratory failure. The only current treatment for pulmonary alveolar proteinosis is “whole lung lavage,” an invasive procedure requiring anesthesia that washes away the accumulation of debris.

After noticing 2 women with the syndrome who unexpectedly improved with oral statin therapy for high cholesterol, researchers exposed cells from patients with pulmonary alveolar proteinosis to statins in a culture. They found statins stimulated the alveolar macrophages, the cells that clear excess cholesterol and proteins. In mouse models, the researchers then showed stain therapy improved markers of the rare lung disease.

Additionally, the study sheds light on the potential of 2 new methods to diagnose pulmonary alveolar proteinosis, researchers noted. One is computer software that analyzes computed tomography scans of the lungs and improves disease severity assessment. The other is measuring cholesterol levels from fluid gathered during lavage treatment in conjunction with an endoscopic evaluation, which could replace the need for risky lung biopsy.

More research is needed, the authors noted, to identify mechanisms of action as well as the safety and potential efficacy of statins in patients with pulmonary alveolar proteinosis.

—Jolynn Tumolo