No sex difference in association between SBP and stroke and ischemic heart disease
Comparison of the Sex-Specific Associations Between Systolic Blood Pressure and the Risk of Cardiovascular Disease: A Systematic Review and Meta-analysis of 124 Cohort Studies, Including 1.2 Million Individuals
Peters SAE, Huxley RR, and Woodward M
BackgroundEstimates of disease burden of elevated blood pressure assume that the association between systolic blood pressure (SBP) and cardiovascular disease (CVD) is similar for men and women. Large-scale pooling studies have however given inconsistent results [1-4]. While one study showed a slightly higher risk of SBP-related stroke for men as compared to women , other studies did not find a sex difference for the association between SBP and fatal stroke [2,4].
Sex differences in hazards have been found for ischemic heart disease (IHD) and acute myocardial infarction (MI) . However, total IHD, fatal IHD or nonfatal MI did not show such an effect .
There has not been a systematic comparison of the relation between SBD and CVD between the sexes. This study therefore performed a systematic review with meta-analysis of prospective cohort studies of the sex-specific associations between SBP with stroke and IHD. A total of 24 studies comprising 124 cohorts was analysed, encompassing data from 1197472 individuals (44% women), who experienced 26176 strokes and 24434 IHD events.
- A pooled multiple-adjusted RR for a 10mmHg increment in SBP showed a 23% higher risk (95%CI: 1.20-1.25) of stroke in women and 24% higher risk (95%CI: 1.20-1.28) for stroke in men. There was no statistically significant sex difference for the risk of stroke (RRR: 0.98, 95%CI: 0.96-1.01, P=0.13).
- No difference in the RRR (women:men ratio of RRs) for stroke was seen based on different age groups, nor for regions or studies. There was some evidence that suggested a sex difference for hemorrhagic stroke (RRR: 0.94, 95%CI: 0.89-0.99).
- The pooled multiple-adjusted RR for the association between SBP and combined IHD showed a 13% higher risk with each 10 mmHg increment in SBP for both women (95%CI: 1.10-1.16) and men (95%CI: 1.10-1.15). Thus, there was no sex difference (pooled RRR: 1.oo, 95%CI: 0.97-1.04, P=0.85).
- No difference in the RRR for IHD was seen based on age-groups. As compared to women, men from Asia had a slightly but significantly increased risk of IHD associated with increased SBP: the pooled RRR of 21 cohorts of non-Asian countries was 1.02 (95%CI: 1.00-1.05) as compared to 0.94 (95%CI: 0.92-0.97) based on 54 Asian cohorts.
ConclusionThis meta-analysis of data of ~1.2 million individuals demonstrates that the association between SBP and risk of IHD and stroke is largely similar in men and women. Both genders have approximately 25% extra risk of stroke and ~15% risk of IHD with each 10 mmHg increment in SBP. However, prevalence of high SBP and other CVD risk factors likely vary between the sexes.
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