Hyperhomocysteinaemia in black patients with cerebral thrombosis

Hyperhomocysteinemia is regarded as a risk factor for stroke but itspathogenetic role has not yet been established in Black patients. Westudied 24 Black patients admitted with cerebral thrombosis, and comparedthem with age- and sex-matched apparently healthy controls from the samecommunity. Total homocysteine (tHcy) (free homocysteine, protein-boundhomocysteine, the disulfide homocystine and the mixed disulfidehomocysteine-cysteine) concentration was 10.91 (4.95-23.05) mumol/l in thestroke patients and 8.73 (3.95-15.10) mumol/l in controls (p = 0.031). Thisdifference could not be explained by differences in vitamin B12, vitamin B6or folate status. A subgroup of nine stroke patients withhypercreatininaemia (> 90 mumol/l, 75% of control concentrations) hadsignificantly higher plasma tHcy concentrations [median (range) 9.10(5.40-15.10) mumol/l] compared with controls [8.65 (3.96-13.89) mumol/l] (p= 0.002). Plasma tHcy concentrations of stroke patients with normal serumcreatinine concentrations were not significantly different to those ofcontrols. Hyperhomocysteinemia in Black patients with stroke may bepartially caused by renal insufficiency. Therefore, whilehyperhomocysteinemia may increase the risk of stroke, it is unlikely to bea primary initiating factor.