The impact of high‑density lipoprotein on oxidant–antioxidant balance in healthy elderly people

INTRODUCTION    There is an inverse relationship between high‑density lipoprotein cholesterol (HDL-C) levels and the risk of atherosclerosis.
OBJECTIVES    The aim of the present study was to assess the oxidant–antioxidant balance in elderly people with different concentrations of HDL-C.
PATIENTS AND METHODS    A total of 541 people aged 60 years or older were examined, of whom 90 individuals with no acute or severe chronic disorders had their waist circumference, body mass index, percentage of body fat, and blood pressure measured. Fasting and 120‑minute glycemia was determined in an oral glucose tolerance test, following which 15 patients with type 2 diabetes were excluded. Fasting plasma levels of lipids, total antioxidant status, and thiobarbituric acid-reacting substances (TBARS), as well ast the activity of erythrocyte superoxide dismutase 1 (SOD‑1) were assessed. Based on HDL-C levels, participants were divided into the high HDL‑C group (≥40.0 mg/dl and ≥50.0 mg/dl for men and women, respectively; n = 50) and the low HDL‑C group (<40.0 mg/dl and <50.0 mg/dl for men and women, respectively; n = 25).
RESULTS    The groups did not differ in terms of age, blood pressure, body mass index, percentage of body fat, and glucose concentration. The high HDL‑C group had lower waist circumference (P <0.02) and lower triglyceride concentrations (P <0.00001). Increased TBARS levels (P <0.0005) was observed in the low HDL‑C group. There were no differences in SOD‑1 activity and total antioxidant status between the groups.
CONCLUSIONS    HDL-C levels, which are known to reflect the antiatherogenic activity of HDL, including antioxidant properties, may indicate increasing oxidative stress in healthy elderly individuals.