Abstract WP245: New Definition of Hypertension and Incident Cerebral Microbleeds: A 7-Year Chinese Urban Community Study

Abstract

Background and Purpose: Cerebral microbleeds (CMBs) are associated with recurrent stroke, dementia and mortality in the general population. Hypertension (blood pressure over 140/90 mmHg) was thought as a crucial risk factor of CMBs in the general population. However, the cutoff for diagnosis of hypertension was lowered to blood pressure over 130/80 mmHg in the 2017 American College of Cardiology / American Heart Association (ACC/AHA) guidelines. Whether the new definition of hypertension remains a potent risk factor of CMBs is questionable. We aimed to analyze the relationship between the new definition of hypertension and incident CMBs in a 7-year longitudinal community study. Methods: This study is part of the Shanghai Aging Study (SAS). 159 participants without stroke or dementia (mean age, 67.7 years) underwent repeated clinical examinations and cerebral MRI at baseline (2009-2011) and follow-up (2016-2018) with a median interval of 6.9 years. CMBs at baseline and follow-up were evaluated on T2*-GRE and SWAN sequence of MRI. We classified baseline blood pressure into four categories: normal BP, elevated systolic blood pressure, stage 1 hypertension and stage 2 hypertension according to the new criteria. We assessed the association of blood pressure categories with incident CMBs by generalized linear models. Results: Participants with incident CMBs had higher baseline systolic blood pressure (SBP) and pulse pressure (PP) than those without incident CMBs. The difference was significant in SBP (P=0.024), and marginally significant in PP (P=0.057). Both stage 1 and stage 2 hypertension were associated with a higher risk of incident CMBs (IRR=2.77, P=0.028; IRR=3.04, P=0.011, respectively). Conclusions: In this 7-year longitudinal study, participants with incident CMBs had higher SBP and PP at baseline. Stage 1 and stage 2 hypertension defined by this new criterion were associated with incident CMBs.