Natural history of idiopathic pulmonary fibrosis

Abstract

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.

Chronic Kidney Disease Predicts Survival in Patients with Idiopathic Pulmonary Fibrosis

“…Among the patients with IPF, the mean age was 69.2 ± 7.5 years, and this group was predominated by males (80%) and ever smokers (84%). Their mean eGFR was 69.5 ± 17.9 mL/min/1.73 m 2 , and 37 patients (30%) were diagnosed with CKD (stages [3][4][5]. At the time of inclusion, 10 patients had previously taken medication for IPF (6 oral corticosteroids, 6 immunosuppressants [azathioprine, cyclosporine, or cyclophosphamide], and 3 pirfenidone), whereas the remaining patients had not previously taken any medication for IPF.…”

“…Demographic factors (age, gender, and smoking history), physiological factors (forced vital capacity [FVC] and diffusing capacity of the lung for carbon monoxide [D LCO ]), radiological factors, and some serum biomarkers have been reported to predict the survival of patients with IPF [4] . Recently, the composite physiologic index (CPI), which is calculated from FVC, forced expiratory volume in 1 s (FEV 1 ), and D LCO , has been proposed to represent the extent of fibrosis and predict the mortality of patients with IPF [5] .…”

When to start and when to stop antifibrotic therapies

“…For this reason, FVC has been commonly used as the primary end-point in clinical trials [9][10][11]. The most important and recent clinical trials have shown that the mean annual rate of FVC decline in placebo groups is ∼200 mL, as compared to 20-30 mL for a normal individual [1,[12][13][14].…”

Sunitinib, a Small-Molecule Kinase Inhibitor, Attenuates Bleomycin-Induced Pulmonary Fibrosis in Mice

“…However, there are still unavoidable adverse effects, including gastrointestinal disorders, skin-related adverse events and elevation in lev-els of alanine and aspartate aminotransferase. These drugs merely slow down the progression of pulmonary function failure (Kim et al 2015). Therefore, further investigations are needed to elucidate critical factors in developing IPF and to identify new potential therapeutic agents.…”

“…IPF was associated with an epithelial-dependent fibroblast-activated process, termed the epithelial to mesenchymal transition (EMT) (Kim et al 2015). Both TGF-β and platelet-derived growth factor (PDGF) signaling play important roles in developing pulmonary fibrosis (Antoniades et al 1990;Hiwatari et al 1997).…”