Homocysteine and ischaemic stroke in men: The Caerphilly study

Abstract

Objective - To assess the risk of ischaemic stroke associated with total serum homocyst(e)ine (tHcy) concentration. Design - Cohort study. Setting - Caerphilly, South Wales. Participants - 2254 men age 50 to 64 years recruited between 1984 and 1988. Results - 107 men developed ischaemic stroke and mean follow up time was 10.2 years. There was no significant difference in mean serum total homocyst(e)ine levels between stroke cases (12.2 μmol 95% CI 11.6 to 13.1) and non-cases (11.7 μmol 95% CI 11.5 to 11.9) (p = 0.14). There was no significant risk for a standard deviation increase in homocyst(e)ine (adjusted hazard ratio = 1.1, 95% CI 0.9 to 1.4). An interaction was observed between homocyst(e)ine and age at entry (p = 0.003). The adjusted odds ratio comparing the top quintile of homocyst(e)ine with the rest was 2.5 (95% CI 1.0 to 6.2) for strokes occurring under 65 years and 0.5 (95% CI 0.2 to 1.3) at 65 years or older (p value for interaction = 0.02). Risk also differed by blood pressure status. The adjusted hazard ratio for a standard deviation increase in homocyst(e)ine was 0.8, (95% CI 0.6 to 1.2) for normotensive men and 1.3 (95% CI 1.1 to 1.7) for hypertensive men (p value for interaction = 0.01). Conclusions - Overall, there is no significant relation between homocyst(e)ine and ischaemic stroke in this cohort. However, its aetiological importance may be greater for premature ischaemic strokes (<65 years) and in hypertensive men.