Characteristics, Outcomes, and Predictors of Mortality of Acute Kidney Injury in a Rural Tertiary Hospital in Southern Nigeria

Abstract

Context: Acute kidney injury (AKI) is a major contributor to global morbidity and mortality in critically ill patients. In Nigeria, AKI is commonly associated with preventable conditions, particularly infections; however, data on its characteristics, outcomes, and predictors of mortality are limited.

Objective: This study assessed the characteristics, outcomes, and predictors of mortality among patients with AKI at the Irrua Specialist Teaching Hospital (ISTH), Edo State.

Materials and Methods: A hospital-based retrospective study was conducted on 200 patients diagnosed with AKI at ISTH. Associations between variables and mortality were assessed using the chi-square test and Fisher’s exact test. Binary logistic regression was used to determine the predictors of mortality at a level of significance of p < 0.05.

Results: The mean participant age was 45.11 ± 23.18 years, with a male predominance (69%). Most cases of AKI were community-acquired (182, 91%), and sepsis/infection was the leading cause of AKI (115, 57.5%). Overall, 162 participants (81%) presented with stage 3 disease, 157 participants (78.5%) required dialysis, 19 participants (9.5%) achieved complete renal recovery, and the mortality rate was 27.5%. Mortality was significantly associated with higher Kidney Disease: Improving Global Outcomes (KDIGO) stage (p = 0.024), elevated blood urea nitrogen (p = 0.022), presence of complications (p = 0.001), dialysis requirement (p = 0.025), and intensive care unit (ICU) admission (p = 0.001). ICU admission (AOR = 0.035, 95% CI = 0.008 – 0.146, p <0.001), dialysis requirement (AOR = 0.313, 95% CI = 0.100 – 0.983, p = 0.047), and place of residence (AOR = 0.430, 95% CI = 0.187 – 0.989) were identified as independent predictors of mortality.

Conclusion: AKI in this setting is predominantly community-acquired and infection-related. Mortality is primarily driven by clinical severity and complications rather than by the underlying cause. Strengthening early detection, infection control, and access to renal and critical care services are essential to improve outcomes in resource-limited settings such as ours.