Clinical risk factors demonstrate an age-dependent relationship with oxidative stress biomarkers in African Americans

Objective: To examine the interaction of oxidative stress biomarkers with age, and also factors that influence oxidative stress such as body mass index (BMI) and fitness in a population of individuals with established higher risk of cardiovascular disease, African Americans. Methods: Blood samples were obtained from healthy college-age and middle-age to older African Americans. Participants underwent a graded exercise test. Superoxide dismutase (SOD) activity, total antioxidant capacity and thiobarbituric acid reactive substances (TBARS) levels were measured. Results: TBARS levels were significantly (P=.001) lower in young participants relative to middle-age to older participants. SOD activity was significantly (P=.001) lower in middle-age to older participants with low fitness relative to participants with normal fitness, and lower (P=.04) in middle-age to older participants that were overweight relative to normal weight participants. Discussion: In a healthy middle-age to older population of African Americans, BMI and fitness are crucial for maintaining a healthy endothelium.