Aging of the lungs in asymptomatic lifelong nonsmokers: findings on HRCT

Abstract

Purpose: To report lung parenchymal findings on high-resolution computed tomography (HRCT) in a population of asymptomatic, never-smoker urban dwellers aged 65 years and older.

Materials and methods: After institutional approval, asymptomatic older patients from the Geriatrics Outpatient Clinic aged 65 years and older (older group) and healthy volunteers aged 30-50 years (younger group) were invited to participate in the study. Asymptomatic, never-smoker subjects considered free of relevant disease after spirometry and echocardiography underwent chest HRCT. Three researchers reviewed every scan, noting the absence/presence and distribution of pre-specified parenchymal findings. Statistical comparisons between groups were performed using appropriate tests with the aid of software.

Results: Forty-seven older and 24 younger subjects were included in this analysis. A higher proportion of women and a longer history of urban dwelling were present in the older group. Parenchymal findings were more prevalent in the older group (78.7 vs. 25% in the younger group; p < 0.001). Parenchymal bands (59.6 vs. 25%; p = 0.007), ground-glass opacities (25.5 vs. 0%; p = 0.006), and septal lines (21.3 vs. 0%; p = 0.013) were more prevalent in the elderly. When only subjects aged 75 years and older were considered as the older group, micronodules, reticular opacities, cysts, and bronchiectases (19.1 vs. 0 % for all comparisons; p = 0.04) were also more frequently found among the elderly.

Conclusion: Parenchymal bands, ground-glass opacities, septal lines, bronchiectasis, micronodules, reticular opacities, and lung cysts were more prevalent among the elderly.