The Incidence of Raised Procoagulant Factors and Hyperhomocysteinaemia in Chinese Patients with Chronic Venous Insufficiency

Abstract

Background For reasons that are poorly understood, there appear to be differences in the prevalence of chronic venous insufficiency (CVI) and venous thromboembolism between Caucasians and Asians. Objectives To compare levels of procoagulant factors and homocysteine (Hcy) in Hong Kong (HK) Chinese and United Kingdom (UK) Caucasian populations of patients with CVI (patients of CEAP clinical stages C4 – C6). Methods HK Chinese and UK Caucasian patients with CEAP clinical grade 4–6 venous disease were enrolled. Patients with conditions known to be associated with thrombophilia (TP) were excluded. UK and HK patients were matched by gender, age (within 5 years) and by CEAP clinical grade. All subjects underwent clinical examination, venous duplex ultrasound, and measurement of Hcy and factors (F) VIII, IX and XI. Results 63 Patients were enrolled in each group: Mean age 64y (HK group); 67y (UK group). 37% were female; 19% had active venous ulceration. One-third of patients in each group had deep venous reflux. High Hcy, FIX and FXI were significantly more common in the UK group. Multiple TP was more common in the UK group: raised levels of ≥2 factors in 26 vs. 14 patients ( P = 0.022, χ 2). Median Hcy (14.3 vs. 10.8 μmol/L; P < 0.0005, Wilcoxon signed rank [WSR]), FIX (131 vs. 115%; P = 0.048), and FXI (114 vs. 97%; P = 0.002) were significantly higher in the UK group. There was no significant difference in FVIII levels. Conclusions Raised procoagulant factors were more common in Caucasians compared with Chinese patients with CVI in this study. As with the inherited thrombophilias, the pattern of raised procoagulant factors in Chinese patients appears to differ from that in Caucasians.