INCIDENCE AND PREDICTORS OF ACUTE KIDNEY INJURY IN PATIENTS PRESENTING WITH HYPERTENSIVE EMERGENCY: A PROSPECTIVE OBSERVATIONAL STUDY

Abstract

Background: Hypertensive emergency (HE) remains a life-threatening condition characterised by severe blood pressure elevation accompanied by acute target organ damage. While acute kidney injury (AKI) represents a frequent and prognostically significant complication of HE, contemporary data on its incidence and predictors using current diagnostic criteria remain limited. Objectives: This study aimed to determine the incidence of AKI among patients presenting with hypertensive emergencies, identify independent clinical and laboratory predictors of AKI, and evaluate the performance of novel biomarkers for early risk stratification. Methods: This prospective observational study was conducted at a tertiary care hospital between January 2024 and February 2025. Consecutive adults presenting with hypertensive emergency (systolic BP >180 mmHg or diastolic BP >110 mmHg with evidence of target organ damage) were enrolled. AKI was defined and staged according to kidney disease: Improving Global Outcomes (KDIGO) 2024 criteria. Demographic, clinical, and laboratory variables were collected on admission. Serum creatinine, cystatin C, high-sensitivity cardiac troponin I, and the triglyceride-glucose index were measured. Multivariable logistic regression analysis identified independent predictors of AKI. Model discrimination was assessed using the area under the receiver operating characteristic curve analysis. Results: Among 267 enrolled patients (mean age 63.1±14.6 years, 59.2% male), AKI occurred in 110 patients (41.2%), with KDIGO stage 1 in 57 (21.3%), stage 2 in 34 (12.7%), and stage 3 in 19 (7.1%). Independent predictors of AKI included admission serum creatinine >1.1 mg/dL (adjusted odds ratio [aOR] 3.91, 95% CI 2.38–6.42, p<0.001), elevated high-sensitivity troponin I (aOR 2.72, 95% CI 1.68–4.41, p<0.001), triglyceride-glucose index ≥9.2 (aOR 2.38, 95% CI 1.46–3.88, p<0.001), systolic blood pressure variability >25% during initial 6 hours (aOR 2.24, 95% CI 1.37–3.66, p=0.001), and Black race (aOR 2.04, 95% CI 1.24– 3.35, p=0.005). A prediction model incorporating these variables demonstrated excellent discrimination (AUC 0.85, 95% CI 0.80–0.89). Conclusion: AKI complicates over 40% of hypertensive emergency presentations, with one-fifth of cases reaching moderate- to-severe stages. Readily available clinical and laboratory parameters enable accurate early risk stratification, potentially guiding intensity of monitoring and therapeutic interventions.