Increased fasting total homocysteine plasma levels as a risk factor for thromboembolism in children

Summary

Elevated total homocysteine (tHcy) concentrations are an inde- pendent risk factor for thromboembolic events in adults. In children with moderate hyperhomocysteinemia data are sparse. Therefore, between 1995 and 2002 we consecutively recruited 163 white pediatric patients with a first symptomatic thromboembolic event and 255 healthy controls (mean age: 6.4 years in patients vs. 6.6 years in controls, range: 3 months to 18 years) and measured fasting tHcy levels. Median tHcy levels in patients were significantly higher (6.6 µmol/l, range 2.9-20.4 µmol/l) than in controls (5.7 µmol/l, 2.0-14.0 µmol/l, p<0.0001). 48 of the 163 patients with thromboembolism (29.5%) versus 26 of the 255 controls (10.2%) had tHcy levels above the age- specific normal 90th percentile (OR 2.9, 95%CI: 1.7-4.8). The odds ratio for children in the highest quintile compared to chil- dren with levels in the lowest quintile was 4.3 (1.6-8.1; highest quintile: median tHcy level 9.6 µmol, range 8.0-20.4), showing a significantly increased risk for thromboembolic disease with even mild hyperhomocysteinemia. We conclude that hyperho- mocysteinemia above the age-specific cut-off values is a risk fac- tor for thromboembolic events in children. Therefore, screen- ing for elevated fasting tHcy levels of patients with thromboem- bolism is recommended to stratify the risk of thromboembo- lism.

Keywords

Homocysteine - hyperhomocysteinemia - thromboembolism - children

^* A. Kosch and H.G. Koch contributed equally

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