Abstract 10191: Associations of Urine Biomarkers of Kidney Tubule Health With Incident Hypertension and Blood Pressure Trajectories in Middle-Aged Adults

Abstract

Introduction: Kidney tubules play a key role in regulating blood pressure (BP). Urine biomarkers of kidney tubule injury associate with incident hypertension (HTN) in older adults with multiple comorbidities. Less is known about these associations in younger adults. Hypothesis: Urine biomarkers of kidney tubular injury and dysfunction associate with incident HTN and greater 10-year rise in BP in middle-aged adults. Methods: In 1,170 participants of the Coronary Artery Risk Development in Young Adults (CARDIA) study (mean age 45±4, 40% black, 56% women) without HTN, cardiovascular disease or kidney disease at the year 20 exam (baseline for this analysis), we measured urine monocyte chemoattractant protein-1, alpha-1-microglobulin, kidney injury molecule-1, epidermal growth factor [EGF], interleukin-18, chitinase-3-like protein 1, and uromodulin. We examined associations of biomarkers with incident HTN (onset of systolic BP ≥130 mmHg or diastolic BP ≥80 mmHg or initiation of BP meds) after baseline in interval-censored Cox models and BP trajectories in linear mixed models adjusted for established risk factors. Results: During a median 9.9 years of follow up (IQR 5.9-10.2), 376 incident HTN events occurred. Compared to the lowest tertile of EGF, the risk of incident HTN was lower in the two higher tertiles in the model adjusted for age, sex, race, and urine creatinine, and in the fully adjusted model (Figure). The mean increase in SBP over 10 years was 3.4 mmHg lower in Tertile 3 vs. Tertile 1 of EGF (95%CI -6.1, -0.7). There were no statistically significant associations of urine EGF with incident HTN or BP trajectories when EGF was modeled as a continuous predictor. There were no statistically significant associations of other biomarkers with incident HTN or BP trajectory. Conclusions: In middle aged adults without HTN, cardiovascular or kidney disease, higher urine EGF levels associated with lower risk of incident HTN and lower 10-year mean rise in BP.