SYSTEMIC OXIDATIVE STRESS AND ITS RELATIONSHIP WITH AGE AND ILLNESS

OBJECTIVE: It has recently been proposed that increased oxidative stre ss may play a role in the aging process and age-associated degenerativ e diseases. DESIGN AND MEASUREMENTS: A cross-sectional study was carri ed out to assess the relationship of circulating antioxidants, namely vitamins E and C, beta-carotene, proteic thiols (P-SH) and ceruloplasm in, and of lipid peroxides, with both aging and aging with disability, i.e., unsuccessful aging. PARTICIPANTS: One hundred healthy free livi ng and 62 disabled octo-nonagenarians and 91 healthy adults were enrol led in the study. RESULTS: Free living and disabled older adults had l ower antioxidant and higher lipid peroxide levels than healthy adults, as well as the disabled older adults compared with free living older persons. Using logistic regression, we observed that plasma concentrat ions of vitamins E and C, P-SH, and lipid peroxides were independently associated with either aging or aging with disability, apparently rep resenting biochemical indicators of patient status. In particular, agi ng and unsuccessful aging were associated with higher levels of lipid peroxides independently of circulating levels of vitamins C and E, sug gesting that the increased oxidative stress was not merely an effect o f a lower dietary intake of antioxidants. Serum ceruloplasmin was sign ificantly higher in free living older adults than in healthy adults, a nd in the disabled compared with free living octo-nonagenarians. CONCL USIONS: Our findings are consistent with the presence of systemic oxid ant load in older adults, and this phenomenon is far more evident in u nsuccessful aging.