Hyperhomocysteinaemia as a Risk Factor for Deep-vein Thrombosis

Choline Deficiency Is Associated With Increased Risk for Venous Catheter Thrombosis

BACKGROUND

Patients with intestinal failure who require long-term parenteral nutrition (PN) develop catheter thrombosis as a complication. This patient group may also develop choline deficiency because of a defect in the hepatic transsulfuration pathway in the setting of malabsorption. This study was undertaken to determine whether choline deficiency is a risk factor for development of catheter thrombosis.

METHODS

Plasma free and phospholipid-bound choline concentrations were measured in a group of 41 patients that required long-term PN. Episodes of catheter thrombosis from onset of PN to the time of blood testing were recorded.

RESULTS

Sixteen (39%) patients developed catheter thrombosis, and 5 of these had recurrent catheter thrombosis. Plasma free choline was 7.7 +/- 2.7 nmol/mL in patients with no history of catheter thrombosis and 6.2 +/- 1.7 nmol/mL in patients with previous catheter thrombosis (p = .076 by Wilcoxon rank-sum test). The partial correlation between plasma free choline concentration and the frequency of clots after controlling for catheter duration was r = -0.33 (p = .038). The relative risk for catheter thrombosis in subjects with a plasma free choline concentration <8 nmol/mL was 10.0, 95% confidence interval (1.134-88.167). Plasma phospholipid-bound choline concentration was 2191.7 +/- 679.0 nmol/mL in patients with previous catheter thrombosis and 2103.3 +/- 531.2 nmol/mL in patients without history of catheter thrombosis (p = NS).

CONCLUSION

Choline deficiency is a significant risk factor for development of catheter thrombosis in patients with intestinal failure who require PN.

Perspective on the hospital incidence rate of deep venous coagulopathy: Clinical and biochemical diagnostic markers

BACKGROUND

Identifying factors contributing to the increased risk of deep venous thrombosis (DVT) in each population is vital, because of its life-threatening outcome. The current study aims to find the diagnostic performance of some laboratory coagulation markers for predicting DVT in an Iranian population complaining of DVT in the lower limbs.

PATIENTS AND METHODS

For this study, 66 consecutive patients with documented DVT, admitted to the Al-Zahra Hospital in Isfahan for the first time, were considered as the case group and 33 patients without DVT documentations were included as the control group. DVT was considered when there was visualization of thrombus or non-compressibility of the vein, confirmed by bilateral lower extremity compression Doppler ultrasonographic examination. Homocysteine, antiphospholipid, and anticardiolipin antibodies were measured in both groups by using sensitive ELISA kits. Protein C was measured via a functional clotting method, and prothrombin was measured by a kinetic, enzymatic assay.

RESULTS

Multivariable analysis showed that the serum homocysteine levels was potentially associated with the presence of DVT after adjusting for age and gender (OR: 1.038, 95% CI: 1.007-1.070, P = 0.017). Comparison of the C statistic showed a partially good discrimination of homocysteine for DVT, with the area under the receiver operating characteristic (ROC) curve being 0.614 and with the optimal cut-off value of 16.5 micromol/L (μmol/L) for men and 14.5 μmol/L for women.

CONCLUSION

Hyperhomocysteinemia could be considered as an independent risk factor for DVT, with an actual acceptable prognostic value, in the Iran population.

Hormonal contraceptives as a risk factor for cerebral venous and sinus thrombosis

This review will focus on recent developments in our understanding of cerebral venous and sinus thrombosis (CVST), as a side effect of combined oral contraceptives (COCs) use. Case-control studies have shown an increased risk of CVST in women who use COCs, especially third-generation contraceptives that contain gestodene or desogestrel. Several studies have indicated that the combination of COCs and thrombophilia greatly increased the risk of CVST, particularly in women with hyperhomocysteinaemia, factor V Leiden and the prothrombin-gene mutation. Women with thrombophilia who developed CVST while taking oral contraceptives should be definitively advised to stop using COCs. These patients should be considered for preventive therapy with low doses of heparin in prothrombotic situations such as bed rest or pregnancy, and the duration of anticoagulation should be considered on a case-by-case basis. Patients may be considered candidates for chronic treatment with antiplatelet agents. The best and most cost-effective screening method for thrombophilia in women who are planning to conceive is selective screening based on the presence of previous personal or family history of either prior extracerebral or cerebral venous thromboembolism events.