Aims Investigation of paraoxonase-1 (PON1) activity with oxidative status parameters and the increased susceptibility to atherogenesis in β-thalassaemia-trait (BTT) subjects.

Methods Sixty BTT subjects and 20 age- and sex-matched healthy controls were enrolled in the study. Serum PON1, total antioxidant capacity (TAC), malondialdehyde (MDA) and carotid artery intima-media thickness (CIMT) were determined. Qualitative detection of β-thalassaemia mutations was carried out.

Results Serum PON1 activity and TAC were significantly lower in BTT subjects than in controls (p<0.001), while MDA and CIMT were significantly higher (p<0.001). In BTT subjects, TAC, MDA, and CIMT levels were significantly correlated with serum PON1 (r=0.945, −0.900, 0.940 and −0.922 respectively). Serum TAC and MDA were significantly correlated (r=–0.979).

Conclusions Oxidative stress is increased, while serum PON1 activity is decreased in BTT subjects. Decrease in PON1 activity is associated with the degree of oxidative stress, anaemia and increase in CIMT. Therefore, BTT subjects may be more prone to development of atherosclerosis.