Brazilian Dialysis Survey 2022 / Censo Brasileiro de Diálise 2022

Abstract Introduction: The Brazilian Dialysis Survey (BDS) is an annual national survey about patients on chronic dialysis that contributes to health policies. Objective: To report the 2022 epidemiological data from the BDS of the Brazilian Society of Nephrology (BSN). Methods: A survey was carried out in Brazilian chronic dialysis centers using an online questionnaire that included clinical and epidemiological aspects of patients on chronic dialysis, dialysis therapy data, and dialysis center characteristics. Results: Overall, 28% (n = 243) of the centers answered the questionnaire. In July 2022, the estimated total number of patients on dialysis was 153,831. The estimated prevalence and incidence rates of patients per million population (pmp) were 758 and 214, respectively. Of the prevalent patients, 95.3% were on hemodialysis (HD, 4.6% of these on hemodiafiltration) and 4.7% on peritoneal dialysis (PD). Only 1.3% of patients were not vaccinated against COVID-19. The prevalence of anemia (Hb < 10g/dL) was 27% and hyperphosphatemia (P > 5.5mg/dL) reached 30%. The estimated overall crude annual mortality rate was 17.1%. Conclusions: The absolute number and prevalence rate of patients on chronic dialysis continue to increase. A growing number of patients were receiving hemodiafiltration. The mortality rate decreased, probably due to the end of COVID-19 pandemic. The conclusions were drawn in the context of relatively low voluntary participation, which imposed methodological limitations on our estimates.

Resumo Introdução: O Censo Brasileiro de Diálise (CBD) é uma pesquisa nacional anual sobre pacientes em diálise crônica que contribui para as políticas de saúde. Objetivo: Informar os dados epidemiológicos de 2022 do CBD da Sociedade Brasileira de Nefrologia (SBN). Métodos: Foi realizada uma pesquisa em centros brasileiros de diálise por meio de um questionário online que incluiu aspectos clínicos e epidemiológicos de pacientes em diálise crônica, dados da terapia dialítica e características do centro de diálise. Resultados: No total, 28% (n = 243) dos centros de diálise ativos cadastrados na SBN responderam ao questionário. Em julho de 2022, o número total estimado de pacientes em diálise era de 153.831. As taxas estimadas de prevalência e incidência de pacientes por milhão (ppm) de habitantes foram 758 e 214, respectivamente. Dos pacientes prevalentes, 95,3% estavam em hemodiálise (HD; 4,6% desses em hemodiafiltração) e 4,7% em diálise peritoneal (DP). Apenas 1,3% dos pacientes não foram vacinados contra a COVID-19. A prevalência de anemia (Hb < 10g/dL) foi de 27% e de hiperfosfatemia (P > 5,5mg/dL) alcançou 30%. A taxa bruta total anual de mortalidade estimada foi de 17,1%. Conclusões: O número absoluto e a taxa de prevalência de pacientes em diálise crônica continuam a aumentar. Um número crescente de pacientes estava em hemodiafiltração. A taxa de mortalidade diminuiu, provavelmente devido ao fim da pandemia da COVID-19. As conclusões foram de um contexto de participação voluntária relativamente baixa, o que impõe limitações metodológicas às nossas estimativas.

Comparison of 1-year survival between patients initiating chronic hemodialysis under public and private health insurance: register-based data analysis from Brazil.

PURPOSE: Brazil has one of the world's highest numbers of patients on hemodialysis (HD). Most dialysis centers are private and perform HD for patients with private and public health insurance. We compared 1-year survival between patients initiating chronic HD with public and private health insurance. METHODS: This is an HD register-based retrospective cohort. Adult patients starting HD from January 2011 to December 2021 were included. Survival analysis was stratified according to the period entered in the HD register. Multivariate Cox regression focused on 1-year survival differences between private and public patients. RESULTS: In the final sample (n = 5114), 68.5% of participants had public and 31.3% to private health insurance, with overall 1-year survival of 92.8% and 89.9%, respectively (p = 0.002). Crude analysis showed a slightly higher survival rate among patients with public health insurance than those with private health insurance (91 vs. 87%, p = 0.030) in the first period (2019-21). However, the adjusted hazard ratio (HR) did not remain significantly higher for patients with private health insurance compared to those with public health insurance (HR = 1.07; 95% CI 0.80-1.41; p = 0.651), even after propensity score matching of the groups by several baseline features. CONCLUSION: Brazilian chronic HD patients funded by either private health plans or the public system have a similar 1-year mortality risk after controlling for several sociodemographic and clinical parameters.

Sex-specific differences in a large cohort of Brazilian incident dialysis patients over 12 years: A retrospective study.

OBJECTIVE: Sex-specific differences in the epidemiology of chronic kidney disease, such as higher prevalence of women on pre-dialysis and men on chronic dialysis treatment, have been reported worldwide. In this regard, data from non-high-income countries are scarce. We aimed to compare the demographic, clinical, and dialysis characteristics of incident dialysis patients, both men and women, in a large cohort of Brazilian patients over a 12-year period. METHODS: This was a multicentric retrospective cohort study coordinated by the Brazilian Society of Nephrology. The study included all adult incident dialysis patients in the Brazilian Dialysis Registry from January 2011 to December 2022. The variables studied encompassed age, skin color, education, CKD etiology, predialysis nephrologist care, dialysis characteristics, and geographic region. Additionally, the sample was analyzed for each of the three 4-year periods over the 12 years of data collection. RESULTS: A total of 24,632 incident dialysis patients were included. Men were 59.1% of the dialysis population, remaining stable over the three 4-year periods. Besides other differences, women started dialysis younger (58.5 ± 16.2 years vs 59.5 ± 14.4 years; p < 0.001), had a lower educational level (less than 8 years at school: 54% vs 44%; p < 0.001), received more predialysis nephrologist care (46.2% vs 44.2%; p = 0.04), and had a higher prevalence of peritoneal dialysis (4.4% vs 3.5%; p = 0.03). CONCLUSION: We consistently observed a higher prevalence of men on dialysis and differences in demographic, clinical, and dialysis characteristics. The underlying reasons for these sex differences still necessitate further clarification.

Brazilian Dialysis Survey 2022.

INTRODUCTION: The Brazilian Dialysis Survey (BDS) is an annual national survey about patients on chronic dialysis that contributes to health policies. OBJECTIVE: To report the 2022 epidemiological data from the BDS of the Brazilian Society of Nephrology (BSN). METHODS: A survey was carried out in Brazilian chronic dialysis centers using an online questionnaire that included clinical and epidemiological aspects of patients on chronic dialysis, dialysis therapy data, and dialysis center characteristics. RESULTS: Overall, 28% (n = 243) of the centers answered the questionnaire. In July 2022, the estimated total number of patients on dialysis was 153,831. The estimated prevalence and incidence rates of patients per million population (pmp) were 758 and 214, respectively. Of the prevalent patients, 95.3% were on hemodialysis (HD, 4.6% of these on hemodiafiltration) and 4.7% on peritoneal dialysis (PD). Only 1.3% of patients were not vaccinated against COVID-19. The prevalence of anemia (Hb < 10g/dL) was 27% and hyperphosphatemia (P > 5.5mg/dL) reached 30%. The estimated overall crude annual mortality rate was 17.1%. CONCLUSIONS: The absolute number and prevalence rate of patients on chronic dialysis continue to increase. A growing number of patients were receiving hemodiafiltration. The mortality rate decreased, probably due to the end of COVID-19 pandemic. The conclusions were drawn in the context of relatively low voluntary participation, which imposed methodological limitations on our estimates.

Hemodialysis in Brazil: differences across geographic regions regarding demographics, laboratory parameters and drug prescription / Hemodiálise no Brasil: diferenças entre regiões geográficas quanto a dados demográficos, parâmetros laboratoriais e prescrição de medicamentos

ABSTRACT Introduction: Brazil has a vast territory divided into five geographic regions with important differences in sociodemographic indices. We aimed to present and compare socio-demographic characteristics, biochemical results, and drug prescription of patients on chronic hemodialysis (HD) treatment in the five geographic regions. Methods: We evaluated data from the Brazilian Dialysis Registry of all adult patients undergoing chronic HD in 2021. Variables included sociodemographic characteristics, serum levels of phosphate, calcium, and albumin, hemoglobin, urea reduction rate, and prescription of phosphate binders, erythropoietin, and intravenous iron. Data from the North and Northeast regions were combined into one group. Results: A total of 13,792 patients (57.9 ± 16.0 years old, 58.5% male, median HD vintage of 31 (11-66) months) from 73 dialysis centers were analyzed. Regional distribution was 59.5% in the Southeast; 21.7% in the South; 5.9% in the Midwest; and 12.9% in the North/Northeast. Sociodemographic features, biochemical results, and medication prescriptions differed across regions. The prevalence of elderly patients was lower in the Midwest and North/Northeast. The South region had the highest prevalence of hyperphosphatemia (41.2%) and urea reduction rate <65% (24.8%), while anemia and hypoalbuminemia were more prevalent in the Southeast, 32.7% and 11.6%, respectively. Conclusion: We found differences in socio-demographics, clinical features, and drug prescriptions across Brazilian geographic regions. Some findings reflect the socio-demographic diversity of the country, while others deserve further elucidation.

Introdução: O Brasil possui um vasto território dividido em cinco regiões geográficas com importantes diferenças nos índices sociodemográficos. Nosso objetivo foi apresentar e comparar características sociodemográficas, resultados bioquímicos e prescrição de medicamentos de pacientes em tratamento de hemodiálise crônica (HD) nas cinco regiões geográficas. Métodos: Avaliamos os dados do Registro Brasileiro de Diálise de todos os pacientes adultos submetidos à HD crônica em 2021. As variáveis incluíram características sociodemográficas, níveis séricos de fosfato, cálcio e albumina, hemoglobina, taxa de redução de ureia e prescrição de quelantes de fosfato, eritropoietina e ferro intravenoso. Os dados das regiões Norte e Nordeste foram combinados em um único grupo. Resultados: Foi analisado um total de 13.792 pacientes (57,9 ± 16,0 anos, 58,5% do sexo masculino, mediana de tempo de HD de 31 (11-66) meses) de 73 centros de diálise. A distribuição regional foi de 59,5% dos pacientes provenientes do Sudeste; 21,7% do Sul; 5,9% do Centro-Oeste; e 12,9% do Norte/Nordeste. As características sociodemográficas, os resultados bioquímicos e as prescrições de medicamentos diferiram entre as regiões. A prevalência de pacientes idosos foi menor nas regiões Centro-Oeste e Norte/Nordeste. A região Sul apresentou a maior prevalência de hiperfosfatemia (41,2%) e taxa de redução de ureia < 65% (24,8%), enquanto a anemia e a hipoalbuminemia foram mais prevalentes no Sudeste, 32,7% e 11,6%, respectivamente. Conclusão: Encontramos diferenças nos dados sociodemográficos, nas características clínicas e prescrições de medicamentos nas regiões geográficas brasileiras. Alguns achados refletem a diversidade sociodemográfica do país, enquanto outros demandam maiores esclarecimentos.

Hemodialysis in Brazil: differences across geographic regions regarding demographics, laboratory parameters and drug prescription.

INTRODUCTION: Brazil has a vast territory divided into five geographic regions with important differences in sociodemographic indices. We aimed to present and compare socio-demographic characteristics, biochemical results, and drug prescription of patients on chronic hemodialysis (HD) treatment in the five geographic regions. METHODS: We evaluated data from the Brazilian Dialysis Registry of all adult patients undergoing chronic HD in 2021. Variables included sociodemographic characteristics, serum levels of phosphate, calcium, and albumin, hemoglobin, urea reduction rate, and prescription of phosphate binders, erythropoietin, and intravenous iron. Data from the North and Northeast regions were combined into one group. RESULTS: A total of 13,792 patients (57.9 ± 16.0 years old, 58.5% male, median HD vintage of 31 (11-66) months) from 73 dialysis centers were analyzed. Regional distribution was 59.5% in the Southeast; 21.7% in the South; 5.9% in the Midwest; and 12.9% in the North/Northeast. Sociodemographic features, biochemical results, and medication prescriptions differed across regions. The prevalence of elderly patients was lower in the Midwest and North/Northeast. The South region had the highest prevalence of hyperphosphatemia (41.2%) and urea reduction rate <65% (24.8%), while anemia and hypoalbuminemia were more prevalent in the Southeast, 32.7% and 11.6%, respectively. CONCLUSION: We found differences in socio-demographics, clinical features, and drug prescriptions across Brazilian geographic regions. Some findings reflect the socio-demographic diversity of the country, while others deserve further elucidation.

Obesity and survival in a national cohort of incident hemodialysis patients: An analysis of the Brazilian Dialysis Registry.

INTRODUCTION: A phenomenon called the "obesity paradox" has consistently been reported in several cohorts of patients on chronic hemodialysis. In this setting, a higher body mass index (BMI) is paradoxically associated with better survival. This study aimed to evaluate the effect of BMI on mortality in patients undergoing chronic hemodialysis using the Brazilian Dialysis Registry. METHODS: This was a retrospective national cohort study with data on incident hemodialysis patients collected between January 2011 to December 2018. Those aged <18 or > 80 years were excluded from the study. The variables studied were the clinical and laboratory data regularly collected at the dialysis units. The variable of primary interest was BMI, represented as the median of the entire dialysis treatment and stratified into four ranges according to the World Health Organization (WHO) classification. The primary outcome was death within 4 years. Cox proportional hazards regression analysis was used to test associations with mortality. FINDINGS: The analyzed sample consisted of 5489 patients from 73 centers in five regions of the country. Of these, 5.9% were underweight, 48.3% were of normal weight, 31.0% were overweight, and 14.7% were obese. The 4-year survival rates in these BMI ranges were 58%, 70%, 75%, and 80%, respectively. The probability of survival for each BMI extract was significantly different from that in the normal-weight range (p < 0.05). In the fully adjusted Cox proportional hazard regression model, BMI > 24.9 kg/m2 remained an independent protective factor for mortality (HR: 0.76, 95% CI: 0.62-0.95, p = 0.016). DISCUSSION: In Brazil, being overweight and obese are protective factors for survival in the chronic hemodialysis population.

Brazilian Dialysis Survey 2021 / Censo Brasileiro de Diálise 2021

ABSTRACT Introduction: The Brazilian Dialysis Survey (BDS) is an important source of national data about people on chronic dialysis that contributes to the formulation of health policies regarding kidney failure. Objective: To report the 2021 epidemiological data from the BDS of the Brazilian Society of Nephrology (BSN). Methods: A survey was carried out in Brazilian chronic dialysis centers using an online questionnaire covering clinical and epidemiological aspects of patients in chronic dialysis, data on dialysis therapy, characteristics of dialysis centers, and the impact of the COVID-19 pandemic of 2021. Results: Thirty percent (n = 252) of the centers answered the questionnaire. In July 2021, the estimated total number of patients on dialysis was 148,363. The estimated prevalence and incidence rates of patients per million population (pmp) were 696 and 224, respectively. Of the prevalent patients, 94.2% were on hemodialysis (HD) (1.8% of these on hemodiafiltration), and 5.8% on peritoneal dialysis (PD); 21% were on the transplant waiting list. The incidence rate of confirmed COVID-19 between January and July 2021 was 1,236/10,000 dialysis patients, and the case-fatality rate reached 25.5%. Up to July 2021, 88.6% of patients had received at least one dose of the anti-SARS-CoV-2 vaccine. The estimated overall and COVID-19 crude annual mortality rates were 22.3% and 5.3%, respectively. Conclusion: The absolute number and the prevalence rate of patients on chronic dialysis continue to increase. Most dialysis patients were vaccinated against COVID-19 during the year. The COVID-19 pandemic was associated to the overall mortality rate.

RESUMO Introdução: O Censo Brasileiro de Diálise (CBD) constitui importante fonte de dados nacionais sobre pessoas em diálise crônica que contribui para a formulação de políticas de saúde. Objetivo: Relatar dados epidemiológicos de 2021 do CBD da Sociedade Brasileira de Nefrologia (SBN). Métodos: Realizou-se pesquisa em centros brasileiros de diálise crônica utilizando questionário online abrangendo aspectos clínicos e epidemiológicos de pacientes em diálise crônica, dados sobre terapia dialítica, características dos centros de diálise e o impacto da pandemia COVID-19 em 2021. Resultados: Trinta por cento (n = 252) dos centros responderam ao questionário. Em Julho de 2021, o número total estimado de pacientes em diálise foi 148.363. As taxas estimadas de prevalência e incidência de pacientes por milhão da população (pmp) foram 696 e 224, respectivamente. Dos pacientes prevalentes, 94,2% estavam em hemodiálise (HD) (1,8% destes em hemodiafiltração), e 5,8% em diálise peritoneal (DP); 21% estavam na lista de espera para transplante. A taxa de incidência de COVID-19 confirmada entre Janeiro e Julho de 2021 foi 1.236/10.000 pacientes em diálise, e a taxa de letalidade atingiu 25,5%. Até Julho de 2021, 88,6% dos pacientes haviam recebido pelo menos uma dose da vacina anti-SARS-CoV-2. As taxas estimadas de mortalidade bruta anual geral e por COVID-19 foram de 22,3% e 5,3%, respectivamente. Conclusão: O número absoluto e a taxa de prevalência de pacientes em diálise crônica continuam aumentando. A maioria dos pacientes em diálise foram vacinados contra COVID-19 durante o ano. A pandemia COVID-19 contribuiu com a taxa de mortalidade geral.

Symptoms for early diagnosis of chronic kidney disease in children - a machine learning-based score.

The objective of this study was to reveal the signs and symptoms for the classification of pediatric patients at risk of CKD using decision trees and extreme gradient boost models for predicting outcomes. A case-control study was carried out involving children with 376 chronic kidney disease (cases) and a control group of healthy children (n = 376). A family member responsible for the children answered a questionnaire with variables potentially associated with the disease. Decision tree and extreme gradient boost models were developed to test signs and symptoms for the classification of children. As a result, the decision tree model revealed 6 variables associated with CKD, whereas twelve variables that distinguish CKD from healthy children were found in the "XGBoost". The accuracy of the "XGBoost" model (ROC AUC = 0.939, 95%CI: 0.911 to 0.977) was the highest, while the decision tree model was a little lower (ROC AUC = 0.896, 95%CI: 0.850 to 0.942). The cross-validation of results showed that the accuracy of the evaluation database model was like that of the training. CONCLUSION: In conclusion, a dozen symptoms that are easy to be clinically verified emerged as risk indicators for chronic kidney disease. This information can contribute to increasing awareness of the diagnosis, mainly in primary care settings. Therefore, healthcare professionals can select patients for more detailed investigation, which will reduce the chance of wasting time and improve early disease detection. WHAT IS KNOWN: • Late diagnosis of chronic kidney disease in children is common, increasing morbidity. • Mass screening of the whole population is not cost-effective. WHAT IS NEW: • With two machine-learning methods, this study revealed 12 symptoms to aid early CKD diagnosis. • These symptoms are easily obtainable and can be useful mainly in primary care settings.

A Cross-Sectional Study on the Prevalence and Risk Stratification of Chronic Kidney Disease in Cardiological Patients in São Paulo, Brazil.

Chronic kidney disease (CKD) provides a worse prognosis for patients with heart disease. In Latin America, studies that analyzed the prevalence and risk stratification of CKD in this population are scarce. We aimed to evaluate CKD prevalence and risk categories in patients of a public referral cardiology hospital in São Paulo, Brazil. This was a cross-sectional study based on a laboratory database. Outpatient serum creatinine and proteinuria results performed between 1 January 2021 and 31 December 2021 were analyzed. CKD was defined by estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2 and proteinuria, by the albumin/creatinine ratio in a spot urine sample (UACR) >30 mg/g. A total of 36,651 adults were identified with serum creatinine levels (median age 72.4 [IQR, 51.0-73.6] years, 51% male). Among them, 51.9% had UACR dosage (71.5% with UACR < 30 mg/g, 22.6%, between 30-300 mg/g, and 5.9% with UACR > 300 mg/g). The prevalence of CKD was 30.9% (15.3% stage 3a, 10.2% stage 3b, 3.6% stage 4, and 1.7% stage 5), and the distribution of patients in the risk categories of the disease was: 52.0% with low-risk, 23.5%, moderate risk, 13.0%, high risk, and 11.2%, very high. In an outpatient setting, the prevalence of CKD in cardiological patients was almost three times (31%) that of the general population; about half of the individuals evaluated (48%) were not screened for an important risk marker (proteinuria), and approximately a quarter of these patients (24%) were in the high or very high CKD risk categories.

A Cross-sectional study on the prevalence and risk stratification of chronic kidney disease in cardiological patients in São Paulo, Brazil

ABSTRACT: Chronic kidney disease (CKD) provides a worse prognosis for patients with heart disease. In Latin America, studies that analyzed the prevalence and risk stratification of CKD in this population are scarce. We aimed to evaluate CKD prevalence and risk categories in patients of a public referral cardiology hospital in São Paulo, Brazil. This was a cross-sectional study based on a laboratory database. Outpatient serum creatinine and proteinuria results performed between 1 January 2021 and 31 December 2021 were analyzed. CKD was defined by estimated glomerular filtration rate (eGFR) 30 mg/g. A total of 36,651 adults were identified with serum creatinine levels (median age 72.4 [IQR, 51.0­73.6] years, 51% male). Among them, 51.9% had UACR dosage (71.5% with UACR < 30 mg/g, 22.6%, between 30­300 mg/g, and 5.9% with UACR > 300 mg/g). The prevalence of CKD was 30.9% (15.3% stage 3a, 10.2% stage 3b, 3.6% stage 4, and 1.7% stage 5), and the distribution of patients in the risk categories of the disease was: 52.0% with low-risk, 23.5%, moderate risk, 13.0%, high risk, and 11.2%, very high. In an outpatient setting, the prevalence of CKD in cardiological patients was almost three times (31%) that of the general population; about half of the individuals evaluated (48%) were not screened for an important risk marker (proteinuria), and approximately a quarter of these patients (24%) were in the high or very high CKD risk categories.

High prevalence of hyperkalemia in Brazilian chronic dialysis patients and differences across geographic regions / Prevalência elevada de hipercalemia em pacientes brasileiros em diálise crônica e diferenças entre as regiões geográficas

Abstract Introduction: Hyperkalemia is a common multifactorial condition of people on chronic dialysis and is associated with mortality. We aimed to inform and discuss the prevalence of hyperkalemia in a large population of chronic dialysis patients in Brazil and its geographic regions. Methods: Prevalence of hyperkalemia (serum potassium ≥6.0 mEq/L) was assessed in the Brazilian Dialysis Survey (BDS) in July 2019, an online survey of voluntary participation in which all dialysis centers registered at the Brazilian Society of Nephrology were invited. Results: Approximately one-third (n=263 of 805) of the Brazilian dialysis clinics participated. The prevalence of hyperkalemia in the whole population was 16.1% (n=7,457 of 46,193; 95%CI=15.8-16.5%,), and varied from 12.1% in the North to 18.7% in the Northeast. Conclusion: We found a high prevalence of hyperkalemia in a large Brazilian chronic dialysis population. A nationwide investigation of risk factors, treatment options, and whether this high prevalence contributes to dialysis mortality is warranted.

Resumo Introdução: A hipercalemia é uma condição multifatorial comum em pessoas em diálise crônica e está associada à mortalidade. Nosso objetivo foi informar e discutir a prevalência de hipercalemia em uma grande população de pacientes em diálise crônica no Brasil e diferenças entre as regiões geográficas. Métodos: A prevalência de hipercalemia (potássio sérico ≥6,0 mEq/L) foi avaliada por meio do Censo Brasileiro de Diálise (CBD) em Julho de 2019, uma pesquisa online de participação voluntária na qual foram convidados todos os centros de diálise registrados na Sociedade Brasileira de Nefrologia. Resultados: Aproximadamente um terço (n=263 de 805) das clínicas de diálise brasileiras participaram. A prevalência de hipercalemia na população total foi de 16,1% (n=7.457 de 46.193; IC95%=15,8-16,5%), e variou de 12,1% no Norte a 18,7% no Nordeste. Conclusão: Encontramos uma elevada prevalência de hipercalemia em umagrande população brasileira em diálise crônica. É necessária uma investigação nacional dos fatores de risco, opções de tratamento e se esta alta prevalência contribui para a mortalidade desta população.

Characteristics and 1-year survival of incident patients on chronic peritoneal dialysis compared with hemodialysis:a large 11-year cohort study.

PURPOSE: Few studies have evaluated patients' characteristics and survival by dialysis modality in Brazil. We evaluated changes in dialysis modality and its survival in the country. METHODS: This is a retrospective database of a cohort with incident chronic dialysis patients from Brazil. Patients' characteristics and one-year multivariate survival risk were assessed considering dialysis modality from 2011 to 2016 and 2017 to 2021. Survival analysis was also performed on a reduced sample after adjustment using propensity score matching. RESULTS: Of the 8295 dialysis patients, 5.3% were on peritoneal dialysis (PD) and 94.7% on hemodialysis (HD). PD patients had higher BMI, schooling and the prevalence of elective dialysis starting in the first period than those on HD. In the second period, PD patients were predominantly women, non-white, from the Southeast region, and funded by the public health system, having more frequent elective dialysis starting and predialysis nephrologist follow-ups than those on HD. There was no difference in mortality comparing PD and HD (HR 0.67, 95% CI 0.39-2.42; and HR 1.17, 95% CI 0.63-2.16; first and second period, respectively). This non-significantly different survival between both dialysis methods was also found in the reduced matched sample. Higher age and non-elective dialysis initiation were associated with higher mortality. In the second period, the lack of predialysis nephrologist follow-up and living in the Southeast region increased the mortality risk. CONCLUSION: Some sociodemographic factors have changed according to dialysis modality over the last decade in Brazil. The one-year survival of the two dialysis methods was comparable.

High prevalence of hyperkalemia in Brazilian chronic dialysis patients and differences across geographic regions.

INTRODUCTION: Hyperkalemia is a common multifactorial condition of people on chronic dialysis and is associated with mortality. We aimed to inform and discuss the prevalence of hyperkalemia in a large population of chronic dialysis patients in Brazil and its geographic regions. METHODS: Prevalence of hyperkalemia (serum potassium ≥6.0 mEq/L) was assessed in the Brazilian Dialysis Survey (BDS) in July 2019, an online survey of voluntary participation in which all dialysis centers registered at the Brazilian Society of Nephrology were invited. RESULTS: Approximately one-third (n=263 of 805) of the Brazilian dialysis clinics participated. The prevalence of hyperkalemia in the whole population was 16.1% (n=7,457 of 46,193; 95%CI=15.8-16.5%,), and varied from 12.1% in the North to 18.7% in the Northeast. CONCLUSION: We found a high prevalence of hyperkalemia in a large Brazilian chronic dialysis population. A nationwide investigation of risk factors, treatment options, and whether this high prevalence contributes to dialysis mortality is warranted.

Prevalence and Determinants of Predialysis Dietitian Follow-Up: Results From the Brazilian Dialysis Registry.

OBJECTIVE: We aimed to evaluate the prevalence and sociodemographic determinants of predialysis dietitian follow-up in a large cohort of Brazilian dialysis patients. METHODS: We retrospectively evaluated data from all incident adult dialysis patients included in the Brazilian Dialysis Registry from January 2011 to September 2021. Predialysis dietitian follow-up was classified as present when a period more than 6 months of dietitian care was reported. Gender, age, skin color, education, body mass index, chronic kidney disease etiology, first chronic dialysis program, healthcare provider, and geographic regions were tested in logistic regression models. RESULTS: Ten thousand three hundred and eighty two patients met the inclusion criteria and 1,254 (12.1%) reported predialysis dietitian follow-up, most of them referred by a nephrologist (94.2%). The independent determinants of dietitian follow-up were older age, white skin color, higher education level, not having diabetes, living in North/Northeast and South (compared to Southeast), and having a nonpublic healthcare provider. When considered only patients under a predialysis care of a nephrologist, higher education, hemodialysis as the first dialysis modality, and living in the North/Northeast and South regions (compared with Southeast) were associated with dietitian follow-up. CONCLUSION: Predialysis dietitian follow-up for more than 6 months in a country where the public health system is the main dialysis provider is still very low. The nephrologist is pivotal for referral to dietitians but socioeconomic factors also seem to play a role in this regard.

Chronic hemodialysis patients with COVID-19 cared for by the public health system have higher mortality than those treated in private facilities: analysis of the Brazilian dialysis registry.

PURPOSE: Brazil is the third country globally in dialysis patients. Little is known about the impact of the type of health insurance on the outcome of these patients after COVID-19. METHODS: We analyzed comorbidities, sociodemographic factors, and dialysis-related parameters from a retrospective cohort study of 1866 Brazilian chronic hemodialysis patients with COVID-19 from Feb 2020-July 2021. We evaluated the influence of health insurance (private vs. public) on the intensive care unit admission and 90 day fatality risk. RESULTS: From 1866 hemodialysis patients, 455 (24%) were admitted to the intensive care unit, and 350 (19%) died. The mean age was 57.5 years, 88% had public health insurance. Crude case-fatality rate was not different between groups (private vs. public risk ratio 1.11; 95% CI 0.82-1.52, p = 0.498). In fully adjusted multivariate models, patients with private health insurance did not have a higher chance to be admitted to an intensive care unit (odds ratio 0.97; 95% CI 0.63-1.50, p = 0.888), but they presented a lower death risk (hazard ratio 0.56; 95% CI 0.37-0.85, p = 0.006). CONCLUSION: The type of health insurance did not influence the access of hemodialysis patients with COVID-19 to an intensive care unit, but patients with private health insurance had a lower mortality risk.

Development of an instrument to predict proliferative histological class in lupus nephritis based on clinical and laboratory data.

OBJECTIVES: To compare the correlations of histological class inferences based on clinical manifestations and laboratory tests between rheumatologists and nephrologists, to determine the associations of clinical and laboratory data with histological classes and to develop an instrument that can assist histological class identification in lupus nephritis (LN). METHODS: Retrospective study based on medical records of 80 systemic lupus erythematosus patients (SLICC criteria classification, 2012) who underwent kidney biopsy between 2010 and 2017. Two rheumatologists and two nephrologists received clinical and laboratory data and answered questions regarding which histological class was expected on kidney biopsy. Kappa (K) coefficient was used to assess agreement between evaluators. A decision tree was constructed using the chi-square interaction detector and logistic regression was performed for the development of the proliferative histological class predictor instrument. RESULTS: The mean age and disease duration were 33 ± 10.3 years and 11.5 ± 6.7 years, respectively. The level of agreement between the evaluators and kidney biopsy was poor (global K 0.364 ± 0.029; p < .001). Analyzing clinical and laboratory variables as predictors of proliferative histological class, patients with abnormal urinary sediment and positive anti-dsDNA antibodies presented 13.96 and 4.96 times higher risks of presenting class III or IV, respectively (p < 0.001). Our instrument has a sensitivity of 87.8% and specificity of 80%, using abnormal urinary sediment, anti-dsDNA antibodies, and serum creatinine as variables. CONCLUSIONS: Rheumatologists and nephrologists with experience in treating LN generated evaluations that correlated weakly with kidney biopsy. When kidney biopsy is unavailable or is contraindicated for medical reasons, instruments based on clinical and laboratory predictors may be helpful.

Brazilian Dialysis Survey 2021.

INTRODUCTION: The Brazilian Dialysis Survey (BDS) is an important source of national data about people on chronic dialysis that contributes to the formulation of health policies regarding kidney failure. OBJECTIVE: To report the 2021 epidemiological data from the BDS of the Brazilian Society of Nephrology (BSN). METHODS: A survey was carried out in Brazilian chronic dialysis centers using an online questionnaire covering clinical and epidemiological aspects of patients in chronic dialysis, data on dialysis therapy, characteristics of dialysis centers, and the impact of the COVID-19 pandemic of 2021. RESULTS: Thirty percent (n = 252) of the centers answered the questionnaire. In July 2021, the estimated total number of patients on dialysis was 148,363. The estimated prevalence and incidence rates of patients per million population (pmp) were 696 and 224, respectively. Of the prevalent patients, 94.2% were on hemodialysis (HD) (1.8% of these on hemodiafiltration), and 5.8% on peritoneal dialysis (PD); 21% were on the transplant waiting list. The incidence rate of confirmed COVID-19 between January and July 2021 was 1,236/10,000 dialysis patients, and the case-fatality rate reached 25.5%. Up to July 2021, 88.6% of patients had received at least one dose of the anti-SARS-CoV-2 vaccine. The estimated overall and COVID-19 crude annual mortality rates were 22.3% and 5.3%, respectively. CONCLUSION: The absolute number and the prevalence rate of patients on chronic dialysis continue to increase. Most dialysis patients were vaccinated against COVID-19 during the year. The COVID-19 pandemic was associated to the overall mortality rate.

Prevalence and risk stratification of chronic kidney disease in a tertiary cardiology hospital: a cross-sectional study

INTRODUCTION: Chronic kidney disease (CKD) is common, preventable and silent in its early stages. Therefore, early detection of this condition in the population at risk, through laboratory tests, is essential. OBJECTIVES: To estimate the CKD prevalence and perform its risk stratification in a tertiary health service specialized in cardiology. METHODS: The study was cross-sectional and based on laboratory records of patients from a public hospital specialized in cardiology. The evaluated tests were serum creatinine and urinary albumin/creatinine ratio (ACR, random sample) performed on an outpatient basis between 01/01/2021 and 12/31/2021. Duplicate exams and patients under 18 years of age were excluded. The estimated glomerular filtration rate (eGFR) was calculated using the CKD-EPI creatinine equation. CKD was defined by eGFR 300mg/g). According to the CKD risk map, individuals with simultaneous creatinine and ACR measurements were stratified into low, moderate, high or very high risk. RESULTS: The sample consisted of 36,651 patients in whom the same number of serum creatinine results and 19,031 ACR results were evaluated (median patients'age 72.5 [51.0-73.6] years, 51.3% male). The prevalence of CKD was 30.9% and patients with stages 3a, 3b, 4 and 5 corresponded to 15.3%, 10.2%, 3.6% and 1.7%, respectively. CKD was more frequent in older age groups: 18- 29 years (2.5%), 30-44 years (8.4%), 45-59 years (25.5%), 60-74 years (30 .7%) and ≥75 years (56.8%) (p<0.001). Patients with albuminuria categories A1, A2 and A3 were 71.5%, 22.6% and 5.9%, respectively. ACR ≥30mg/g was not associated with age: 18-29 years (23.3%), 30-44 years (23.4%), 45-69 years (26.0%), 60-74 years (28 .5%) and ≥75 years (36.9%) (p=0.671). Patients with simultaneous measurements of serum creatinine and ACR were 19,031 and their distribution in the CKD risk categories was: low (52.0%), moderate (23.8%), high (13.1%) and very high risk (11.2%). CONCLUSIONS: The results showed that CKD is present in about 30% of the patients assisted in the cardiology institute evaluated. In up to half of the patients, the risk of major outcomes such as hospitalization, need for renal replacement therapy, and death was moderate, high, or very high.