The inter-arm systolic blood pressure difference and risk of cardiovascular mortality: A meta-analysis of cohort studies.

The inter-arm systolic blood pressure difference (SBPD) is recommended to be in relation to potential cardiovascular disease (CVD). Previous studies yielded controversial results about the association between an inter-arm SBPD ≥ 10 mmHg or ≥15 mmHg and the risk of cardiovascular mortality. Therefore, we conducted this meta-analysis to investigate this association. We searched PubMed and Embase databases through December 31, 2014, and examined the references of retrieved articles to identify relevant cohort studies. We utilized Newcastle-Ottawa scale to assess the quality of included studies and calculated the summary risk estimates in a fixed/random-effect model. All data analyses were conducted using STATA version 11.0. A total of seven studies were identified. Compared with participants with an inter-arm SBPD < 10 mmHg, the pooled hazard ratio (HR) of CVD mortality of those with an inter-arm SBPD ≥ 10 mmHg was 1.58 (95% CI: 1.3-1.93), and the pooled HR of cardiovascular mortality of participants with an inter-arm SBPD ≥ 15 mmHg versus those with an inter-arm SBPD < 15 mmHg was 1.88 (95% CI: 1.33-2.66). The findings from the present meta-analysis indicated that the detection of an inter-arm SBPD may define a subpopulation at high risk of CVD events.