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BACKGROUND: Brazil has the largest Public Health System providing universal coverage for chronic dialysis. The objective was to describe the number, sociodemographic, and clinical characteristics of patients undergoing kidney replacement therapy (KRT) by dialysis within the Public Health System in Brazil. METHODS: We carried out a retrospective cohort study analyzing the database from the Brazilian Public Health System, focusing on procedures related to KRT. The study encompassed both prevalent and incident patients who underwent KRT in Brazil between 2015 and 2023. RESULTS: We observed an increase in the number and prevalence rate of dialysis patients from 2015 to 2023. We also noticed an increase in the age at dialysis initiation and in the prevalence of mixed-race patients and a reduction in the proportion of those undergoing peritoneal dialysis and with arteriovenous fistula. We identified an upward trajectory in the values of single-pool Kt/V over the years, contrasting with a decline in hemoglobin levels. The overall estimated prevalence rate of dialysis patients increased from 654 per million population (pmp) to 792 pmp over the years. The survival rates of incident KRT patients at 12 and 96 months were 81% and 60%, respectively. CONCLUSION: We reported an increase in the age at which dialysis began and a decline in the adoption of peritoneal dialysis over the years. While there have been some improvements over the years resulting in better adequacy of hemodialysis as measured by Kt/V, controlling certain parameters such as hemoglobin levels has remained challenging.
RESUMO
BACKGROUND: Thrombotic Microangiopathy (TMA) is a syndrome characterized by the presence of anemia, thrombocytopenia and organ damage and has multiple etiologies. The primary aim is to develop an algorithm to classify TMA (TMA-INSIGHT score). METHODS: This was a single-center retrospective cohort study including hospitalized patients with TMA at a single center. We included all consecutive patients diagnosed with TMA between 2012 and 2021. TMA was defined based on the presence of anemia (hemoglobin level < 10 g/dL) and thrombocytopenia (platelet count < 150,000/µL), signs of hemolysis, and organ damage. We classified patients in eight categories: infections; Malignant Hypertension; Transplant; Malignancy; Pregnancy; Thrombotic Thrombocytopenic Purpura (TTP); Shiga toxin-mediated hemolytic uremic syndrome (STEC-SHU) and Complement Mediated TMA (aHUS). We fitted a model to classify patients using clinical characteristics, biochemical exams, and mean arterial pressure at presentation. RESULTS: We retrospectively retrieved TMA phenotypes using automatic strategies in electronic health records in almost 10 years (n = 2407). Secondary TMA was found in 97.5% of the patients. Primary TMA was found in 2.47% of the patients (TTP and aHUS). The best model was LightGBM with accuracy of 0.979, and multiclass ROC-AUC of 0.966. The predictions had higher accuracy in most TMA classes, although the confidence was lower in aHUS and STEC-HUS cases. CONCLUSION: Secondary conditions were the most common etiologies of TMA. We retrieved comorbidities, associated conditions, and mean arterial pressure to fit a model to predict TMA and define TMA phenotypic characteristics. This is the first multiclass model to predict TMA including primary and secondary conditions.