Background: Mean arterial pressure (MAP) has been proved to be an independent risk factor for stroke. In this study, we explored whether cumulative exposure of MAP in patients with hypertension is more associated with the occurrence of stroke.
Methods: In this prospective follow-up cohort study of hypertension from June 2010 to May 2020, 9136 participants without previous stroke at recruitment were included, of whom 492 (5.4%) had a first incident stroke during the study period (418 ischemic strokes and 74 hemorrhagic strokes). The study exposure factor was cumulative MAP, and was quartered from low to high (Q1, Q2, Q3, Q4). We analyzed the risk of first stroke using multivariable adjusted Cox regression models and used stratified analysis to further explore the risk of stroke in hypertensive patients with different characteristics.
Results: Increased cumulative MAP in patients with hypertension were associated with risk for ischemic stroke (HR, Q2, 1.23 [95% CI, 0.91– 1.67]; Q3, 1.35 [95% CI, 1.01– 1.82]; Q4, 1.55 [95% CI, 1.15– 2.10]; P=0.035). Furthermore, this trend persisted after stratified analysis in men (HR, Q3, 1.76[1.10– 2.82]; Q4, 2.05[1.28– 3.28]), aged 60 or above (HR, Q4, 1.63[1.13– 2.35]) and higher body mass index (BMI) populations (HR, Q3, 1.48[1.02– 2.14]; Q4, 1.59[1.09– 2.32]). In contrast, cumulative MAP was not significantly associated with stroke in women, age under 60, and non-obese individuals.
Conclusion: Increased cumulative MAP is an independent risk factor of ischemic stroke in patients with hypertension. Special attention should also be paid to men, aged 60 or older, or those with a higher BMI.
Keywords: cumulative mean arterial pressure, stroke, hypertension, blood pressure, population science