Objective: Previous studies suggest that hyperhomocysteinemia may be a risk factor for arterial and venous thrombosis. We retrospectively analyzed data from 75 patients with thrombosis.
Patients and methods: Thirty-four patients had arterial thrombosis, 22 venous thrombosis and 19 venous and arterial thrombosis. Of the 75 patients (49 men and 26 women, mean age 49 +/- 15 years) about two-thirds had recurrent episodes of thrombosis.
Results: Hyperhomocysteinemia was defined as serum homocysteine level above 14.1 mumol/l (mean + 2.7 SD in healthy subjects) and was found in 67 patients (89%, CI95% = 80-95). Mean total homocysteine concentration was 21.6 +/- 13.6 mumol/l for the 75 patients. About half of the patients were smokers, 35% had hypertension and 25% high serum cholesterol. There was no significant relationship between serum homocysteine level and smoking status, hypertension or serum cholesterol level. Ten patients (13%, CI95% = 7-23) had low serum cobalamin (< 150 pmol/l). Serum folates were < or = 10 nmol in 41% of the patients in the arterial thrombosis group (CI95% = 25-59), in 27% in the venous thrombosis group (CI95% = 11-50), and in 31% in the arterial and venous thrombosis group (CI95% = 13-57). Thirteen patients received vitamin B supplementation. Hyperhomocysteinemia decreased in 12/13 patients (CI95% = 64-100) and returned to normal values in 9/13 patients (69%, CI95% = 38-91).
Conclusion: Our data show that hyperhomocysteinemia is frequently found in arterial and venous thrombosis. Further studies are needed to determine the clinical impact of homocysteine lowering therapy.