Abstract P418: Increased Pro-neurotensin/neuromedin N is Associated With Incident Ischemic Stroke

Abstract

Introduction: The neuropeptide neurotensin (NT) has been linked to cardiovascular and metabolic disease risk. Through measurement of its stable equimolar precursor, pro-neurotensin/neuromedin N (pro-NT/NMN), hyperactivity of NT has been associated with aggregate cardiovascular outcomes that include stroke. However, the exclusive association of pro-NT/NMN with incident ischemic or hemorrhagic stroke has not been studied. Hypothesis: Higher serum pro-NT/NMN is associated with incident ischemic and hemorrhagic stroke. Methods: Prospective case-cohort study in the REasons for Geographic and Racial Differences in Stroke (REGARDS) study. From 2003-2007, REGARDS enrolled 30,239 White or Black adults aged ≥45. Pro-NT/NMN was measured by immunoassay in 464 ischemic stroke cases, 49 hemorrhagic stroke cases, and 800 non-cases from a random cohort. Cox proportional-hazards models were used to calculate hazard ratios (HR) of stroke by pro-NT/NMN quartiles and per standard deviation (SD) of log pro-NT/NMN. Model 1 (both stroke types) included demographic factors as covariates, Model 2A (ischemic only) added ischemic stroke risk factors, and Model 2B (hemorrhagic only) added hemorrhagic stroke risk factors. Results: The table shows an increased HR of ischemic stroke for those in the 4th vs 1st-quartile pro-NT/NMN in Model 1 with a trend of increased risk across quartiles; this was attenuated in Model 2A. Prebaseline diabetes and coronary artery disease were the largest confounders of ischemic stroke risk, with each accounting for 19% of the association observed in Model 1. There was no association of pro-NT/NMN with hemorrhagic stroke in either model. There were no interactions of race or sex with log pro-NT/NMN. Conclusions: Higher pro-NT/NMN is associated with increased risk of ischemic stroke after adjusting for demographics, but this was not independent of stroke risk factors. No significant association with hemorrhagic stroke was observed; this analysis was limited by a small number of events.