Elevated lipoprotein (a) and apolipoprotein B to AI ratio in South Asian patients with ischaemic stroke

Abstract

Background: Stroke is a continuing cause of excess cardiovascular disease (CVD) mortality amongst migrants from the Indian subcontinent (South Asians) living in Britain. However, little is known about the dyslipidaemia associated with stroke in South Asians. In particular, the highly atherogenic lipoprotein (a) [Lp(a)] and high apolipoprotein (Apo) B to AI ratio are emerging risk factors for CVD.

Methods: Using a case-control study, we investigated features of the dyslipidaemia in South Asian patients with stroke compared with South Asian subjects with no history of clinically detectable stroke. We studied 55 consecutive South Asian patients with ischaemic stroke (confirmed on computerised scan of the brain) and 85 controls.

Results: The stroke patients were significantly older than controls (65.2 vs. 59.8 years, p = 0.001), but were similarly matched for male gender (63.6 vs. 61.2%), smoking habit (20.7 vs. 18.1%) and presence of type 2 diabetes (25.5 vs. 19.3%). There were no differences between serum total cholesterol (p = 0.07) and high-density lipoprotein cholesterol (p = 0.08) between the groups, but stroke patients had higher serum triglycerides (p = 0.005). Mean [95% confidence interval (CI)] Apo B to AI ratio was higher amongst stroke patients [1.0 (0.9-1.0) vs. 0.7 (0.7-0.75), p < 0.001]. Similarly, geometric mean serum Lp(a) was significantly higher (p = 0.037) in stroke patients [19.9 mg/dl (14.0-28.5)] vs. controls [15.1 mg/dl (11.4-20.1)]. On logistic regression, stroke was independently associated with age and Apo B to AI ratio (p < 0.01).

Conclusion: The present study suggests that Lp(a) and the Apo B to AI ratio are associated with ischaemic stroke in South Asians. A prospective analysis is needed to elucidate the role of Lp(a), Apo B and AI as risk factors for ischaemic stroke in this population, as well as the effects of intervention.