Background: An altered balance of oxidants/antioxidants is one of the pathological mechanisms of many age-dependent disorders. We aimed to investigate the age-related airways oxidative stress, using non invasive, safe and repeatable techniques; to evaluate the correspondence between systemic and local oxidative stress in healthy subjects of different age ranges; to analyse the correlation between systemic and local oxidative stress with lung function and with cognitive impairment.
Methods: Thirty consecutive healthy high school graduated subjects (8 M, 22 F), divided in three ranges of age (< 35; between 35 and 60; > 60 years) were enrolled. All subjects underwent oxygen free radicals and exhaled nitric oxide measurement (by the diacron reactive oxygen metabolites test and by a rapid-response chemiluminescence nitric oxide analyzer), lung function tests, and cognitive impairment scales (Mini Mental State Examination and Geriatric Depression Scale).
Results: A significant increase of oxygen free radicals, exhaled nitric oxide, and Geriatric Depression Scale score and a significant decrease of forced expiratory volume in 1 second and forced expiratory vital capacity from younger to older subjects were identified. Moreover, the significant positive correlation between oxygen free radicals and exhaled nitric oxide, and between oxygen free radicals and exhaled nitric oxide with Geriatric Depression Scale score were found. The significant negative correlation between forced expiratory volume in 1 second and oxygen free radicals or exhaled nitric oxide was also demonstrated.
Conclusions: Our data supports the role of progressive local oxidative stress in damaging the lung function and in inducing depression symptoms.