Aging and IPF: What Is the Link?

Idiopathic pulmonary fibrosis (IPF) is a progressive and usually lethal interstitial lung disease of unknown etiology that is characterized by epithelial cell injury and aberrant activation, expansion of the mesenchymal cell population with the formation of fibroblast/myofibroblast foci, and exaggerated extracellular matrix accumulation. IPF is an aging-related disease, and most patients are over 60 years of age at the time of clinical presentation and diagnosis. Age also influences mortality, and the median survival time is significantly shorter in older individuals compared with younger patients. However, the fundamental mechanisms linking aging to IPF remain unclear. In this chapter, we will discuss some of the modifications naturally occurring in the elderly that may be implicated in the pathogenesis of IPF, including endoplasmic reticulum stress, oxidative stress, mitochondrial dysfunction, dysregulated autophagy, telomere attrition, and a number of epigenetic changes.