Abstract P415: Interleukin-17a And Incident Hypertension In The Reasons For Geographic And Racial Differences In Stroke (REGARDS) Study

Abstract

Background: Inflammation is implicated in hypertension’s etiology. IL-17A is a cytokine representing specific immune pathways. Its association with incident hypertension in adults is unknown. Objective: Determine risk of incident hypertension among adults by level of IL-17A. Methods: In 2003-2007, REGARDS enrolled 30,239 US Black and White adults aged ≥45 years from the 48 contiguous states; a second visit occurred in 2013-16. The Biomarkers as Mediators of Racial Disparities in Risk Factors (BioMedioR) substudy included 4,400 gender-race stratified REGARDS participants who attended both visits. Hypertension was defined with a blood pressure threshold of 140/90 mm Hg or reported use of antihypertensive medications. We excluded those in BioMedioR with prevalent hypertension at baseline. IL-17A was measured from baseline samples with an ELISA. Because of a gender*IL-17A interaction on incident hypertension results were gender-stratified. Modified Poisson regression estimated relative risk (RR) of incident hypertension by IL-17A tertiles in models adjusting for known confounders of the inflammation-hypertension relationship. Results: Among the 1,885 participants (mean [SD] age 62 [8] years, 25% Black race, 55% women), incident hypertension occurred in 35% each of men and women. Higher IL-17A was associated with greater hypertension risk in the crude model for women, but not men (Figure). Adjusting for confounders attenuated this association in women. Conclusions: Higher IL-17A is associated with greater risk of hypertension in women in crude models only. How IL-17A and other specific inflammatory cytokines interrelate to hypertension’s onset is unclear.