Preface

Idiopathic pulmonary fibrosis (IPF) is the most common and important type of idiopathic interstitial pneumonia, characterized by chronic, progressive fibrosing interstitial pneumonia of unknown etiology with a high fatality rate. The incidence and prevalence of the disease increase with age. Worldwide, IPF affects more than 3 million people. In the United States and Europe, the reported incidence of IPF is 2.8–9.3 per 100,000 per year and the prevalence is 18–495 cases per 100,000 adults depending on the age of the cohort. Regional variance has been seen, suggesting that environmental factors play a role.

Over the past decades, we have seen tremendous advancement in the diagnosis and treatment of IPF, which has led to a better understanding of the disease's epidemiology, diagnostics, and optimal treatment modalities. There has been a big push to decrease the time to diagnosis from symptom onset, as it can take one to two years. The pathogenesis of the disease is complex and it is important to rule out several other diseases that can lead to pulmonary fibrosis. The hallmark of IPF is the usual interstitial pneumonia (UIP) pattern seen on high-resolution computed tomography (HRCT) and histology. The diagnosis requires a multidisciplinary team approach, and several guidelines have been published in recent years to help clinicians diagnose this disease in a timely manner.

Recent guidelines have updated the diagnostic modalities and have accepted transbronchial cryobiopsy as an acceptable alternative to surgical biopsy. Moreover, progressive pulmonary fibrosis has now been defined as having two of the following three criteria: physiological progression, radiological progression, and worsening symptoms.

Two antifibrotic drugs are now available, which are not curative but have shown to significantly slow down the decline in lung function associated with IPF. Some recent guidelines have given a conditional recommendation to nintedanib, while more research is suggested for pirfenidone (which was the first to make its way into IPF treatment).

This book describes the epidemiology and diagnosis of IPF in detail. There has been a significant advancement in biomarkers and thus we have included a chapter on biomarkers in IPF. In the area of therapeutics, the book discusses pharmacological management as well as exacerbation of IPF. IPF is a complex disease and gastroesophageal reflux (GERD) has been shown to play a role. As such, there is a chapter addressing the role of GERD in IPF. The book ends with a discussion of pulmonary involvement in Sjogren's disease. Lung transplant remains the cornerstone of management of IPF and despite treatment with antifibrotic agents, most patients with this disease will progress to advanced end-stage lung disease.

We hope this book will update clinicians' knowledge and aid them in taking care of patients with IPF.

### **Salim Surani, MD, MPH, MSHM, FACP, FAASM, FCCM, FCCP**

Adj. Clinical Professor of Medicine and Pharmacology, Texas A&M University, Texas, USA

> **Venkat Rajasurya** Multicare Health System, Tacoma, WA, USA
