[Plasma total homocysteine and pulmonary thromboembolism]

To investigate whether the elevated plasma homocysteine increases the risk of pulmonary thromboembolism in the Chinese population.

Sixty-nine patients with pulmonary thromboembolism and 90 sex- and age-matched healthy controls were recruited, and the patients were diagnosed using lung ventilation/perfusion scan and/or ultrafast CT as well as medical history. The concentration of plasma total homocysteine (tHcy) was measured with high performance liquid chromatography and environmental factors were collected.

No significant difference was seen in family history of pulmonary thromboembolism and cardiovascular diseases, cigarette smoking, alcoholic drinking, oral contraceptive and body mass index between cases and healthy controls. The concentration of plasma tHcy in cases was significantly higher than that in healthy controls (16.60 mumol/L +/- 1.75 mumol/L vs 12.48 mumol/L +/- 1.47 mumol/L; t = 3.821, P < 0.05), and adjusting for environmental factors did not change the significance. The plasma tHcy in the isolated pulmonary thromboembolism patients was lower than that in the patients who had lower limb deep venous thrombosis, but no significant difference was found. Compared with normal plasma tHcy, hyperhomocysteinemia was associated with a 4.99-fold risk of pulmonary thromboembolism.

Our results show that the elevated plasma tHcy increases the risk of pulmonary thromboembolism, and hyperhomocysteinemia is an independent risk factor of pulmonary thromboembolism in the Chinese population.