Global incidence and mortality of idiopathic pulmonary fibrosis: a systematic review

Introduction: As idiopathic pulmonary fibrosis emerges as an important public health problem, there is a need to coordinate data on incidence and mortality globally. This study aims to systematically assess all available studies to investigate the global burden of disease. Methods: Medline and Embase databases were searched systematically for all population-based studies of incidence or mortality of idiopathic pulmonary fibrosis. Clinical case series and prevalence studies were excluded. The search was supplemented using Google search engine, hand-searching of references and conference abstracts. Data were extracted independently by two authors using a pre-specified proforma, with assessment of methodological quality. Results: 34 studies were identified providing data from 21 countries from 1968-2012. 28 studies reported incidence data, and eight reported mortality data. In studies from year 2000 onwards, we estimated a conservative incidence range of 3-9 cases per 100,000 per year for Europe and North America. Incidence was lower in East Asia and South America. The majority of studies showed an increase in incidence over time. Conclusions: The incidence of idiopathic pulmonary fibrosis is increasing worldwide, and rates are coming together across countries. Current data suggest incidence is similar to that of conditions such as stomach, liver, testicular and cervical cancers