Clinical characteristics of idiopathic pulmonary fibrosis patients with diabetes mellitus: the national survey in Korea from 2003 to 2007

Evidence suggests that diabetes mellitus (DM) is associated with idiopathic pulmonary fibrosis (IPF). According to the new IPF guidelines, high-resolution computed tomography (HRCT) is an essential means of diagnosing IPF. We investigated the relationship between IPF and DM in patients treated between 2003 and 2007. Newly diagnosed IPF patients in large university teaching hospitals in Korea were enrolled from January 2003 to December 2007. We retrospectively analyzed 1,685 patients using the interstitial lung disease (ILD) registry. In total, 299 IPF patients (17.8%) also had DM. The mean age of our subjects was 68.0 ± 9.4 yr. HRCT showed significantly more reticular and honeycomb patterns in IPF patients with DM than in IPF patients without DM (P = 0.014, P = 0.028, respectively). Furthermore, significantly higher incidences of hypertension, cardiovascular diseases, and other malignancies (except lung cancer) were found in IPF patients with DM than in IPF patients without DM. In conclusion, IPF patients with DM are more likely to have the usual interstitial pneumonia (UIP) pattern, including reticular and honeycomb patterns, on HRCT than are those without DM.