Elevated homocysteine levels in patients with Raynaud's syndrome

Objective. Patients with Raynaud's phenomenon (RP) have vasomotor dysregulation, the etiology of which has not yet been elucidated. We investigated plasma levels of homocysteine and folate in patients with primary or secondary RP in comparison with healthy subjects. Methods. Plasma from patients with RP, either primary (n = 10) or secondary to scleroderma (n = 10), and from healthy subjects (n = 20) was obtained for homocysteine determination using high performance liquid chromatography. Results. Patients with primary and secondary RP had significantly higher homocysteine concentrations (mean 15.5 ± 4.1 and 11.6 ± 6.2 μmol/l, respectively; p < 0.05) compared to healthy individuals (mean 5.9 ± 2.0 μmol/l). Patients with primary RP had significantly lower plasma levels of folate in comparison with patients with secondary RP or healthy individuals. Conclusion. This is the first study to show higher plasma levels of homocysteine in patients with RP. Given the obscure etiology of this disorder, these findings may provide new clues in the understanding of vasomotor dysfunction in RP.