Natural history of idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is a parenchymal lung disease characterized by progressive interstitial fibrosis. IPF has a poor prognosis, with a median survival time of 2-3 years from diagnosis, but varying from a few months to a decade. The natural history of IPF is highly variable and the course of disease in an individual patient is difficult to predict. Some patients with IPF experience rapid decline, others progress much more slowly, and some patients show periods of relative stability interspersed with acute deteriorations in respiratory function. Many clinical, radiographic, serologic, and histopathologic variables have been shown to predict mortality in IPF. However, the accuracy of these predictors varies due to the retrospective nature of some of the studies and variations in study design. The ability to identify clinical characteristics that predict disease progression and survival would be useful for counseling patients, treatment decision-making, and prompt consideration for lung transplantation. A number of indices for predicting mortality in patients with IPF are available, but they require further validation. As high-resolution computed tomography scans become more widely available and patients with IPF are diagnosed earlier, survival times following diagnosis will improve. Early referral to interstitial lung disease specialty centers is important for accurate diagnosis and may be associated with improved outcomes. The goal of this review is to examine the natural history of IPF, discuss predictors of mortality, and highlight the importance of prompt diagnosis and referral for patients with IPF.