Incidence and outcomes of neonatal acute kidney injury (AWAKEN): a multicentre, multinational, observational cohort study

Jennifer G Jetton, Louis J Boohaker, Sidharth K Sethi, Sanjay Wazir, Smriti Rohatgi, Danielle E Soranno, Aftab S Chishti, Robert Woroniecki, Cherry Mammen, Jonathan R Swanson, Shanthy Sridhar, Craig S Wong, Juan C Kupferman, Russell L Griffin, David J Askenazi, Neonatal Kidney Collaborative, David T Selewski, Subrata Sarkar, Alison Kent, Jeffery Fletcher, Carolyn L Abitbol, Marissa DeFreitas, Shahnaz Duara, Jennifer R Charlton, Ronnie Guillet, Carl D'Angio, Ayesa Mian, Erin Rademacher, Maroun J Mhanna, Rupesh Raina, Deepak Kumar, Namasivayam Ambalavanan, Ayse Akcan Arikan, Christopher J Rhee, Stuart L Goldstein, Amy T Nathan, Alok Bhutada, Shantanu Rastogi, Elizabeth Bonachea, Susan Ingraham, John Mahan, Arwa Nada, Patrick D Brophy, Tarah T Colaizy, Jonathan M Klein, F Sessions Cole, T Keefe Davis, Joshua Dower, Lawrence Milner, Alexandra Smith, Mamta Fuloria, Kimberly Reidy, Frederick J Kaskel, Jason Gien, Katja M Gist, Mina H Hanna, Sangeeta Hingorani, Michelle Starr, Catherine Joseph, Tara DuPont, Robin Ohls, Amy Staples, Surender Khokhar, Sofia Perazzo, Patricio E Ray, Mary Revenis, Anne Synnes, Pia Wintermark

Single-center studies suggest that neonatal acute kidney injury (AKI) is associated with poor outcomes. However, inferences regarding the association between AKI, mortality, and hospital length of stay are limited due to the small sample size of those studies. In order to determine whether neonatal AKI is independently associated with increased mortality and longer hospital stay, we analyzed the Assessment of Worldwide Acute Kidney Epidemiology in Neonates (AWAKEN) database. All neonates admitted to 24 participating neonatal intensive care units from four countries (Australia, Canada, India, United States) between January 1 and March 31, 2014, were screened. Of 4273 neonates screened, 2022 (47·3%) met study criteria. Exclusion criteria included: no intravenous fluids ≥48 hours, admission ≥14 days of life, congenital heart disease requiring surgical repair at <7 days of life, lethal chromosomal anomaly, death within 48 hours, inability to determine AKI status or severe congenital kidney abnormalities. AKI was defined using a standardized definition -i.e., serum creatinine rise of ≥0.3 mg/dL (26.5 mcmol/L) or ≥50% from previous lowest value, and/or if urine output was <1 mL/kg/h on postnatal days 2 to 7. Incidence of AKI was 605/2022 (29·9%). Rates varied by gestational age groups (i.e., ≥22 to <29 weeks =47·9%; ≥29 to <36 weeks =18·3%; and ≥36 weeks =36·7%). Even after adjusting for multiple potential confounding factors, infants with AKI had higher mortality compared to those without AKI [(59/605 (9·7%) vs. 20/1417 (1·4%); p< 0.001; adjusted OR=4·6 (95% CI=2·5-8·3); p=<0·0001], and longer hospital stay [adjusted parameter estimate 8·8 days (95% CI=6·1-11·5); p<0·0001]. Neonatal AKI is a common and independent risk factor for mortality and longer hospital stay. These data suggest that neonates may be impacted by AKI in a manner similar to pediatric and adult patients. US National Institutes of Health, University of Alabama at Birmingham, Cincinnati Children's, University of New Mexico.