A clinical study of idiopathic pulmonary fibrosis based on autopsy studies in elderly patients

Objectives The prevalence of idiopathic pulmonary fibrosis (IPF) tends to be greater in the elderly although the precise outcome is not known. The present study investigated the outcome of IPF in elderly patients whose pathological diagnosis corresponded to usual interstitial pneumonia (UIP) on autopsy findings. Methods In a consecutive autopsy series, (n=4,554 cases), complete information was obtained in 86 cases in which the clinical and pathological diagnosis was IPF and UIP, respectively. Results Mean subject age was 80.5 years and there were 52 males and 34 females. Median survival time (MST) was 3.5 years overall. Dyspnea ranking by the MRC dyspnea scale (DR) on admission was closely related to the outcome. When MST was compared between DR0 and DR1, or DR2 and DR3, the former patient group survived significantly longer than the latter (p<0.05). Twenty percent of patients died of severe respiratory failure. Other causes of death were disease progression of IPF (10.5%), bacterial pneumonia (23.3%) and lung cancer (17.4%). The patients in the young-elderly group (age <75) survived for a significantly longer period than those in the old-elderly group (age greater than or equal to75) (MST; 5.5 vs 2.0 years; p<0.001). Both lung cancer and pneumonia were significantly more prevalent among IPF patients than among non-IPF patients; these IPF with lung cancer profoundly reflected the smoking history of IPF patients. Conclusions The poor outcome in IPF in elderly patients was characterized by more severe dyspnea, advanced age and co-morbidity.