Abstract TMP51: A VA Observational Study Examining the Mortality Benefit of Various Post-ischemic Stroke/tia Hypertension Goals - Is There a Too Low?

Abstract

Introduction: Joint National Committee (JNC)-8 goal blood pressure (BP) recommendation of < 140/90 mmHg has been supplanted by 2017 ACC/AHA goal of < 130/80 mmHg for patients with ischemic stroke/TIA. Understanding potential mortality benefit for patients reaching ACC/AHA goal is needed. Hypothesis: Stroke/TIA patients reaching ACC/AHA goal BP will experience lower 1-year all-cause mortality compared to those reaching JNC-8 BP goals. Methods: This is a retrospective cohort of Veterans with stroke/TIA (N=39,053) who received their longitudinal outpatient primary care within a Veterans Administration Medical Center between 10/2014 and 9/2018. Patients were excluded (n=25,381) if they had missing or physiologically improbable BP values, died, or had less than 1 year of follow-up for analysis of 1-year mortality. We calculated average SBP during 90 days after discharge and assessed it in categorical form (≤115 mmHg, 106-115 mmHg, 116-130, mmHg, 131-140 mmHg, and >140 mmHg) and continuous form. Multivariate COX proportional hazard regression was used to examine the relationship between average SBP groups and time to mortality 90 days after discharge up to 1 year. In multivariate logistic regression, we used continuous SBP along with its quadratic term to predict 1-year mortality. Results: A total of 12,337 eligible patients were included in the final analysis. COX proportional regression demonstrated a statistically significant higher risk of death among patients with SBP lower than 105 mmHg as compared to those with > 140 mmHg (HR = 1.79, 95% CI= 1.37-2.34), but no statistical differences were found in other SBP groups. Predicted probability of 1-year mortality generated from the logistic regression was plotted and showed a “U” shaped relationship between SBP and mortality, whereas SBP ranges encompassing both AHA/ACC and JNC-8 goal BP recommendations are found on the “flat” part of the curve. Conclusions: In considering BP reached by 90-days, there was no differential 1-year all-cause mortality benefit between JNC-8 and ACC/AHA BP recommendations, whereas patients experiencing low SBPs were at increased risk for higher mortality. Providers should be aware of the association between lower SBP and higher mortality when treating BP.