Outcome of patients who were incidentally diagnosed with idiopathic pulmonary fibrosis: How early in the disease should we identify patients?

Abstract

Background: Idiopathic pulmonary fibrosis (IPF) is diagnosed incidentally in some patients with minimal or no respiratory symptoms. The clinical features of such patients are unknown. Herein we aimed to clarify the prevalence, clinical course, and prognostic factors of patients who were incidentally diagnosed with IPF.

Methods: The files of consecutive patients with newly diagnosed IPF were retrospectively reviewed to determine the methods involved in their diagnosis, and their outcomes.

Results: Among a total of 107 patients with newly diagnosed IPF, 35 (32.7%) were diagnosed incidentally, including 18 undergoing annual health check-ups and 17 undergoing assessment for other medical problems. The median survival from the time of diagnosis was 4.9 years for the 35 patients diagnosed incidentally, which was comparable to the median survival of 3.9 years for the 72 who were not diagnosed incidentally. The body mass index (BMI) was the sole independent predictor of survival (hazard ratio 0.78, 95% confidence interval 0.65-0.93, p = 0.006) in patients diagnosed incidentally.

Conclusions: Nearly one third of patients with IPF were diagnosed incidentally, and their survival was still poor. Identifying patients during the earliest stage of IPF, particularly those with a low BMI, is warranted.

Keywords: Body mass index; Health check-up; Idiopathic pulmonary fibrosis; Survival.