Total antioxidant levels, gender, and age as risk factors for DNA damage in lymphocytes of the elderly

During past years, the association of oxidative stress with DNA damage and its possible clinical translation into chronic degenerative illnesses, such as: atherosclerosis, cancer, diabetes mellitus and Alzheimer's disease, ha s been demonstrated. In addition, it has been pointed out that age and gend er are factors that influence the generation of DNA damage: however, this i s still controversial. We have previously reported the results: of a study of 88 subjects older than 60 years of age in whom DNA damage is related wit h serum levels of total antioxidants. The results of this study demonstrate a greater frequency of DNA damage in elderly persons with normal levels of antioxidants, in addition to males, and in the younger group of subjects, i.e., 60-69 years. In this work, we enlarged our study sample to 160 elderl y subjects; in this way, we were able to evaluate the consistency of the in fluence of total antioxidants, age, and gender on the magnitude and grade o f DNA damage in lymphocytes of the elderly. The results demonstrated that 4 5% of the subjects showed DNA damage, measured by an alkaline unicellular e lectrophoresis technique (comet assay). Similarly, 62% of the subjects pres ented low levels of total antioxidant levels measured by a colorimetric met hod (Randox Kit). A greater percentage of DNA damage was observed in subjec ts with normal levels of antioxidants (48%) compared with subjects with low levels (43%), although the difference was not statistically significant. T he group of subjects 70 years of age or older showed a greater percentage o f DNA damage (50%) than the group of subjects of 60-69 years of age (41%). However, the difference was again not statistically significant (P > 0.05). With respect to gender, 64% of males and 38%, of females: had DNA damage w ith an odds ratio (OR) of 2.86 and a 95% confidence interval (CI) of 1.31-6 .32 (P < 0.05). In the logistic regression analysis, the interaction of the male sex variables with low antioxidants had an OR of 2.5 (CI 95%, 1.33-3. 68; P < 0.01). We conclude that the interaction of male sex factors-low lev els of antioxidants would justify the indication of antioxidant dietetic su pplements. (C) 2001 Elsevier Science Ireland Ltd. All rights: reserved.