Association of age and admission mean arterial blood pressure in patients with stroke - Data from a national stroke registry

Elevated blood pressure (BP) upon admission is common in patients with ischemic stroke (IS) and intracerebral hemorrhage (ICH). Older patients have a higher prevalence of stroke, but data on admission mean arterial pressure (MAP) patterns in older patients with stroke are scarce. All 6060 patients with IS (72%), ICH (8%) and transient ischemic attack (TIA; 20%) with data on BP and hypertension status on admission in the National Acute Stroke Israeli Registry were included. Admission MAP in the emergency department was studied by age group (<60, 60-74 and ≥75 years) and stroke type. Linear regression models for admission MAP were produced, including age group, gender, hypertension status and stroke severity as covariates. Interactions between hypertension and age were assessed. Lower MAP (s.d.) was associated with older ages in hypertensive patients (113 (18) mm Hg for age <60 years, 109 (17) for age 60-74 years and 108 (19) for age ≥75 years, P<0.0001) but not in non-hypertensive IS patients. Among patients with ICH and TIA, a significant negative association of MAP with age was observed for hypertensive patients (P=0.015 and P=0.023, respectively), whereas a significant positive association with age was found in non-hypertensive patients (P=0.023 and P=0.038, respectively). In adjusted regression models, MAP was significantly associated with hypertension in IS, ICH and TIA patients. The interaction between hypertension and age was significantly associated with MAP in IS and ICH patients. In hypertensive patients, the average admission MAP was lower in persons at older ages.