Researchers in Japan identified several risk factors for an acute exacerbation, or sudden disease worsening, in people with idiopathic pulmonary fibrosis (IPF), including cardiovascular disease and older age, especially in men.
The study, “Risk factors for an acute exacerbation of idiopathic pulmonary fibrosis,“ was published on July 11 in the journal Respiratory Research.
IPF refers to the thickening and scarring (referred to as fibrosis) of lung tissue, causing increasing difficulty in breathing. Its varied clinical course makes treatment complicated, since some patients experience rapid deterioration while most have slower disease progression — differences that are not well understood.
Acute exacerbations can be sudden and difficult to predict in these patients, but urgent to treat. Understanding their likely risk factors could potentially aid in both preventing and treating them.
The researchers, led by Tomoyuki Kakugawa of the Department of Respiratory Medicine, Unit of Translational Medicine, Nagasaki University Graduate School of Biomedical Sciences, reviewed the medical charts of 65 patients with IPF from January 1999 to September 2014. They used a method known as the official 2011 idiopathic pulmonary fibrosis ATS/ERS/JRS/ALAT Update Statement to retroactively diagnose patients with IPF based on symptoms.
Overall, the team was able to find several IPF acute exacerbation risk factors, including having heart disease, and higher levels of blood markers. The markers included two known as lactate dehydrogenase, and surfactant protein-D level. Specific blood cells called neutrophils and eosinophils were also higher in fluid taken from the lungs. In addition, treatment with medications that suppress the immune system predicted IPF acute exacerbation.
The GAP risk assessment system was an additional predictor of the risk of IPF acute exacerbation. This tool provides mortality estimates for people with IPF based on their age, gender and symptoms. Increased age, male gender, and more lung symptoms — seen in measurements like how much air a person can forcibly exhale and the amount of oxygen in the lungs — elevate the risk of death for IPF patients.
Overall, having heart disease, higher GAP measurements(≥II), and a higher number of eosinophils in lung fluid samples increased the risk of acute exacerbations in this patient population. Immunosuppressant treatments were associated with IPF acute exacerbations, which could be causal but may also indicate more severe symptoms in those individuals taking them.
The information derived from this study could aid physicians in treating and, possibly, preventing acute exacerbations in this patient population.