Epidemiologia da injúria renal aguda dialítica no Rio de Janeiro: um grande centro urbano em um país em desenvolvimento

Abstract

Acute kidney injury (AKI) is a complex condition with a wide range of presentations, ranging from minor changes in renal function to severe organ failure. AKI is associated with significant mortality, which increases with the severity of the presentation and reaches mortality above 50% in the most severe spectrum when there is an indication for artificial renal support (ARS). As in other developing countries, there is a marked lack of epidemiological data on this condition in Brazil. This study proposes a comprehensive and unprecedented analysis of the epidemiology of dialysis-requiring AKI, when ARS is required, using an extensive database – NefroWeb® – in patients treated in 170 Rio de Janeiro's private and public hospitals and medical facilities. The study cohort comprises 17,158 pediatric and adult patients, analyzed over eleven years (2002–2012). We analyzed the data by hierarchical logistic regression models and mixed-effects Cox regression to compare survival between age strata, etiological groups, and different hospital administrations and socioeconomic indicators. We produced three manuscripts that explored the following issues; a) comprehensively describe the epidemiology of AKI in an urban center of an emerging country, exploring risk factors, clinical presentation, and outcomes; b) in-depth description of the diagnoses associated with AKI, stratifying by age groups; c) describe differences between types of the hospital (public vs. private) and the impact of socioeconomic indicators on mortality. A systematic review on AKI epidemiology in pediatrics was the fourth manuscript produced. Altogether, the findings point to severe disease, with high mortality rates (71.6%) being higher in the extremes of age. AKI was mainly hospital-acquired (72.6%), occurred predominantly in the intensive care unit (ICU) (84.9%), and was associated with multiple organ failure. The median age was 75 years, ranging from newborns to centenarians. Community-acquired pneumonia was the most frequent admission diagnosis (23.8%), and sepsis was the leading precipitating cause (72.1%). After infectious etiologies, the cardiovascular etiologies group dominated the scenario. Poor outcomes were associated with age, mechanical ventilation, vasopressor support, liver dysfunction, type 1 cardiorenal syndrome, number of organ failures, admission sepsis, later sepsis, the Charlson score, and ICU admission. Community-acquired AKI, male gender, and pre-existing chronic kidney disease were associated with better outcomes. Despite the significant difference between socioeconomic characteristics between patients treated in private and public hospitals, there was no significant difference in mortality, primarily determined by the factors already mentioned. Our study adds vital information on the real-world epidemiology of dialytic AKI, with considerable clinical detail. In the studied cohort, the AKI phenotype was more similar to high-income countries than the pattern traditionally associated with developing countries.