#3311 INDEPENDENT PREDICTORS FOR COMMUNITY-ACQUIRED ACUTE KIDNEY INJURY: A PROSPECTIVE COHORT STUDY
Authors: Correa Eric , Lussim Lygia , Carbonara Cinthia , Barreto Joaquim , Bueno Rodrigo 
Published: June 2023

Abstract

Background and Aims
Acute Kidney Injury (AKI) is a syndrome characterized by an abrupt drop in glomerular filtration and/or a decrease in urinary output. The awakening to a different kind of AKI that also occurs outside the hospital named community-acquired AKI (CA-AKI) occurred in 1991, however, few data have been published about its epidemiology, risk factors and outcome, especially in low-income countries. The recognition of risk factors for CA-AKI and development of symptom-based risk tool that aims to predict the risk of AKI might be able to avoid delays in its recognizing, improve the timely diagnosis and patient outcomes in this frequent syndrome. We aimed to assess CA-AKI incidence, characteristics and independent risk factors associated with CA-AKI; to evaluate the discriminatory capacity of a clinical score tool to AKI prediction to predict CA-AKI in our sample.

Method
We conducted a prospective observational study of general medical admissions to a tertiary hospital in Campinas (São Paulo) between 10th January 2019 and 16th September 2021; we included patients ≥ 14 years, medical suspicion of infection (or confirmed) and /or presence of at least one of the signs or symptoms on admission: fever, dyspnea, decrease in urine output, edema, hypotension, hemodynamic shock, jaundice, petechiae, ecchymosis or decreased level of consciousness. We excluded patients with stage 5 chronic kidney disease at baseline and pre-existing renal replacement therapy (undergoing dialysis and renal transplantation), and also patients with COVID diagnosis. All patients included were assessed utilizing a symptom-based risk score to predict the development of severe AKI, the need for dialysis and mortality. Patients were subjected to complete history taking, socioeconomic and education data were collected. Healthy literacy was assessed using the test of functional health literacy in adults – short version (S- TOFHLA). Predictors of CA-AKI risk were assessed using multivariate logistic regression analysis. Patients were followed up until discharged hospital. The study outcomes were development of CA-AKI, hospital mortality, dialytic need.

Results
We enrolled 261 patients. CA-AKI was diagnosed in 65 (25%) patients. The CA-AKI patients were older [59 (51-66) vs. 54 (38-65) years, p = 0,02], had higher basal serum creatinine [0,7 (0,5–0,9) vs. 0,6 (0,5-0,8) mg/dL; p = 0,01], lower baseline estimated glomerular filtration rate (eGFR) [103 (88–113) vs. 109 (97–121) mL/min/1,73 m2; p = 0,01] and lower eGFR on admission [64 (44 – 81) vs. 104 (82 – 116) mL/min/1,73 m2; p = 0,0001]. Liver and heart disease were most common comorbidities in the group CA-AKI [10 (16%) vs. 14 (7%) patients, p = 0.04 and 21 (33%) vs. 39 (20%), p = 0,03, respectively]. The risk score did not show significant accuracy to predicting CA-AKI, however, logistic regression showed that scores ≥7 points (OR 95% CI 1.282, 6.133 p = 0.010) followed by age (OR 95% CI 1.007, 1.044 p = 0.008] and liver disease (95% CI 1.063, 6.379 p = 0,036) were independent factors associated with increased risk for CA-AKI in our population. A higher percentage of patients in our sample declared household income &lt; $ 719.73 (month) and the CA-AKI group maintained the same distribution. Only 41 (16%) patients were able to perform the S-TOFHLA and 18 (44%) were considered inadequate or insufficient health literacy. For hospitalized patients, the mean hospital stay in CA-AKI group was longer [8 (4-18) vs. 4 (2-11) days p = 0,001] than without CA-AKI. Overall mortality rate during the follow up was 5% (13 patients), need dialysis 1% (2 patients) and were not statistically significant between the groups.

Conclusion
Healthy literacy, education, and social class did not show association with CA-AKI; dialysis needed and mortality were not different between the groups CA-AKI or without CA-AKI. Covariates and factors associated with risk for CA-AKI were age, liver disease and scores ≥7 points. The main limitation of our study was not feasible to screen all the patients due to the high numbers seen daily.