Despite the relationship of idiopathic pulmonary fibrosis (IPF) with advancing age, little is known about the epidemiology of interstitial lung diseases (ILD) in the elderly. Here we describe the diagnoses, clinical characteristics, and outcomes of patients who were elderly at the time of ILD diagnosis.
Among subjects from a prospective cohort study of ILD, elderly was defined as age > 70. Diagnoses were derived from a multi-disciplinary review. Differences between elderly and non-elderly groups were determined using chi-square and ANOVA testing.
Of the 327 subjects enrolled, 80 (24%) were elderly. The majority of elderly subjects were white and male. The most common diagnoses were unclassifiable ILD (45%), IPF (34%), hypersensitivity pneumonitis (8%), and connective tissue disease ILD (11%). Most elderly subjects (74%) with unclassifiable ILD had an imaging pattern inconsistent with usual interstitial pneumonia (UIP). There were no significant differences in pulmonary function or three-year mortality between non-elderly and elderly subjects combined, or in a subgroup analysis of those with IPF.
While IPF was the single most common diagnosis, the majority of elderly subjects had non-IPF ILD. Our findings highlight the need for every patient with new-onset ILD, regardless of age, to be surveyed for exposures and findings of connective tissue disease. Unclassifiable ILD was common among the elderly, but for most the radiographic pattern was inconsistent with UIP. While the effect of ILD may be more pronounced in the elderly due to reduced global functionality, ILD was not more severe or aggressive in this group.