Determinants of oxidative stress related to gender : relevance of age and smoking habit

Background: Magnitude and major causes of oxidative stress may be different between sexes, although limitedly addressed in clinical studies with controversial results. The present study aimed to determine whether any gender-related difference exists concerning oxidative stress in a population of 332 subjects of both sexes, in a wide age range, with and without cigarette smoking habit. Methods: The Oxidative-INDEX was calculated after evaluation of serum hydroperoxides (ROMs) and total antioxidant capacity (OXY) by means of commercial kits (d-ROMs and Oxy-adsorbent Tests, Diacron, Italy) subtracting the OXY standardized variable from the ROMs standardized variable. Results: The Oxidative-INDEX resulted higher in women with respect to men (p < 0.001), in smokers (p < 0.01) than in non-smokers, and correlated with cigarette number (p < 0.01), age (p < 0.001), and post-menopausal status (p < 0.001). The multivariate analysis identified age, high blood pressure, and smoking habit as factors independently associated with the Oxidative-INDEX in men, whereas cigarette smoking and age represented the independent risk factors for an elevated oxidative stress status in women. Conclusions: Gender-based differences in oxidative stress levels may provide a biochemical basis for the epidemiologic differences in the disease susceptibility between sexes, and suggest different strategies for risk assessment, diagnosis, and treatment specifically targeted to men and women.