Xiao-Fei Zhang1, John Attia, Catherine D'Este, Xiao-Yan Ma. 1. Centre for Clinical Epidemiology and Biostatistics, School of Medical Practice and Population Health, University of Newcastle, Australia. zhxfus@yahoo.com
Abstract
BACKGROUND AND PURPOSE: Previous studies have suggested that blood pressure is a particularly important risk factor for stroke in Chinese, and that the magnitude of the effect may be greater than in Caucasians. We performed a meta-analysis in order to define the magnitude of the risk of stroke associated with hypertension among Chinese, and to compare the magnitude of this risk with Caucasians. METHODS: We searched Medline from 1966 to 2004, plus Chinese Medical Literature databases from 1977 to 2003 for Caucasian and Chinese studies. Results were pooled using the random effects model, and heterogeneity and publication bias were checked. RESULTS: For a 10 mmHg increase in systolic blood pressure, the pooled risk ratio was 1.44 [95% confidence interval (CI)] 1.39-1.51 for ischaemic stroke, and 1.5 (95% CI 1.45-1.57) for haemorrhagic stroke in Chinese, versus 1.19 (95% CI 1.15-1.23) for total stroke in Caucasians. The pooled odds ratio for hypertension measured dichotomously (defined as > or =160/95 mmHg) was 5.8 (95% CI 4.7-7.2) among Chinese versus 1.93 (95% CI 1.7-2.2) among Caucasians for ischaemic stroke; and 7.2 (95% CI 5.3-9.7) in Chinese versus 3.1 (95% CI 2.5-3.9) in Caucasians for haemorrhagic stroke. CONCLUSION: The risk of stroke associated with hypertension is consistently and significantly greater in Chinese than Caucasians. This may help genetic epidemiologists to dissect the cause of stroke, and emphasizes the particular importance of hypertension control in the Chinese population.
BACKGROUND AND PURPOSE: Previous studies have suggested that blood pressure is a particularly important risk factor for stroke in Chinese, and that the magnitude of the effect may be greater than in Caucasians. We performed a meta-analysis in order to define the magnitude of the risk of stroke associated with hypertension among Chinese, and to compare the magnitude of this risk with Caucasians. METHODS: We searched Medline from 1966 to 2004, plus Chinese Medical Literature databases from 1977 to 2003 for Caucasian and Chinese studies. Results were pooled using the random effects model, and heterogeneity and publication bias were checked. RESULTS: For a 10 mmHg increase in systolic blood pressure, the pooled risk ratio was 1.44 [95% confidence interval (CI)] 1.39-1.51 for ischaemic stroke, and 1.5 (95% CI 1.45-1.57) for haemorrhagic stroke in Chinese, versus 1.19 (95% CI 1.15-1.23) for total stroke in Caucasians. The pooled odds ratio for hypertension measured dichotomously (defined as > or =160/95 mmHg) was 5.8 (95% CI 4.7-7.2) among Chinese versus 1.93 (95% CI 1.7-2.2) among Caucasians for ischaemic stroke; and 7.2 (95% CI 5.3-9.7) in Chinese versus 3.1 (95% CI 2.5-3.9) in Caucasians for haemorrhagic stroke. CONCLUSION: The risk of stroke associated with hypertension is consistently and significantly greater in Chinese than Caucasians. This may help genetic epidemiologists to dissect the cause of stroke, and emphasizes the particular importance of hypertension control in the Chinese population.