Large Chest Lymph Nodes in IPF Patients Tied in Study to Higher Risk of Mortality
People with idiopathic pulmonary fibrosis (IPF) who have three or more abnormally large lymph nodes in the area of the lungs and heart — a condition known as mediastinal lymph node enlargement (LNE) — have an increased risk of mortality and faster disease progression, a study found.
The study, “Mediastinal lymph node enlargement in idiopathic pulmonary fibrosis: relationships with disease progression and pulmonary function trends,” was published in the journal BMC Pulmonary Medicine.
IPF is a serious lung disease of unknown origin in which the thickening and stiffening of lung tissue lead to permanent and irreversible scarring (fibrosis), which in turn compromises a person’s ability to breathe. Despite current anti-fibrotic medications, most IPF patients continue to worsen.
Thus, “accurate monitoring of disease progression in IPF is crucial for predicting prognosis and optimizing management, including the appropriate timing of supportive care and the prompt referral for lung transplantation,” investigators wrote.
High-resolution computed tomography (HRCT) lung scans are one of the tools physicians use to diagnose and monitor the progression of IPF.
Statistics indicate that up to 58% of IPF patients show signs of LNE in chest CT scans. This percentage rises to up to 70% among those who also have a distinct pattern of usual interstitial pneumonia, one of the telltale signs of IPF.
“To date however, it is unknown whether the enlargement of mediastinal lymph nodes may be used to identify patients with more rapid functional deterioration, or to indicate response to currently available antifibrotic treatments,” the researchers wrote.
Now, investigators in Italy reported the findings of a study aimed at determining if LNE could be linked to faster disease progression and higher mortality rates in people with IPF.
The study involved a total of 152 IPF patients who had been referred to the interstitial lung disease (ILD) center of the Fondazione Policlinico Universitario “A. Gemelli” IRCCS, in Rome, between January 2014 and November 2018. Of these patients, 135 (89%) received treatment with anti-fibrotic medications during follow-up, which lasted on average 19 months.
Patient chest CT scans were examined by two expert thoracic radiologists to assess the presence of enlarged lymph nodes, which were defined as those measuring at least 10 mm (about .4 inches) in diameter.
More than half (62%) of the patients had at least one enlarged mediastinal lymph node visible on chest CT scans that had been performed within a year of their diagnosis. Among those who showed signs of LNE, most (66%) had two or more lymph nodes measuring at least 10 mm in diameter, and 33% had three or more abnormally large lymph nodes.
Statistical analyses — performed after the researchers normalized the data to take into account the patients’ GAP stage, a disease severity measure — showed that those who had three or more enlarged lymph nodes visible in chest CT scans at the study’s start had a 5.03 times higher risk of mortality and a 2.99 times higher risk of disease progression, compared with those without LNE.
Additionally, the team discovered that 57 of the 62 patients (92%) who had LNE at the study’s start continued to show signs of lymph node enlargement, even after receiving anti-fibrotic therapy during follow-up.
“We demonstrated that the presence of [three or more enlarged mediastinal lymph nodes] on CT scan is independently associated with higher risks of mortality and clinically significant disease progression in a cohort of IPF patients despite antifibrotic treatment,” the investigators wrote.
“Altogether, our results support the utility of mediastinal LNE in the risk stratification of the heterogeneous IPF population,” the team concluded.