Age, Homocysteine, and oxidative stress: Relation to hypertension and type 2 diabetes mellitus

Abstract

Objectives: Hyperhomocysteinemia and oxidative stress are independent risk factors for cardiovascular events, which occur more frequently in old age. We evaluated these parameters in relation to age and the presence of hypertension and type 2 diabetes mellitus. Methods: Two hundred eighty-two subjects (female/male: 142/140; 141 were >65 years and 141 were <65 years; mean age 73.9 ± 6.6 years and 52.5 ± 8.2 years, respectively) were randomly recruited from those attending our institution. Blood pressure, anthropometric parameters, oxidative stress parameters (reactive oxygen species [ROS] and malondialdehyde [MDA]), and homocysteine levels were evaluated in participants. Results: Homocysteine (2.9 ± 0.06 vs. 2.3 ± 0.03 µmol/L, p < 0.001) and oxidative stress (ROS: 10.8 ± 0.3 vs. 8.1 ± 0.3 mmol/L, p < 0.001; MDA: 1.62 ± 0.05 vs. 1.21 ± 0.05 nmol/mL, p < 0.001) were significantly higher in older vs. younger subjects without hypertension or diabetes. However, homocysteine and MDA were not significantly different in older vs. younger hypertensive subjects (homocysteine: 3.0 ± 0.03 vs. 2.9 ± 0.04 µmol/L, p  =  NS; MDA: 1.7 ± 0.07 vs. 1.4 ± 0.06 nmol/mL, p  =  NS) and in older vs. younger diabetic hypertensive subjects (homocysteine: 3.02 ± 0.05 vs. 2.9 ± 0.05 µmol/L, p  =  NS; ROS: 10.7 ± 0.7 vs. 9.7 ± 0.8 mmol/L, p  =  NS; MDA: 1.6 ± 0.10 vs. 1.5 ± 0.12 nmol/mL, p  =  NS). Conclusions: Aging is accompanied by elevated homocysteine and oxidative stress levels similar to those observed in younger subjects with hypertension or diabetes mellitus, independent of age. Hence, these conditions appear to accelerate the age-dependent increase in homocysteine and oxidative stress. © 2009 American College of Nutrition.