Respiratory sarcopenia screening in dialysis patients: cross-sectional and multicentre study protocol

BACKGROUND

Respiratory sarcopenia is characterized by the weakness of respiratory muscles associated with sarcopenia due to aging or systemic diseases such as chronic kidney disease (CKD). Patients with CKD undergoing dialysis are particularly susceptible to respiratory muscle weakness caused by factors such as fluid overload and electrolyte imbalance. This weakness not only affects ventilation but also impairs oxygen uptake and delivery to muscle tissue, potentially leading to severe sarcopenia. Thus, the objective of this study is to conduct a respiratory sarcopenia screening in patients with CKD undergoing haemodialysis (HD) and peritoneal dialysis (PD).

METHODS

This is an observational, cross-sectional and multicentre study conducted between March 2023 and March 2025. The study was approved by the Research Ethics Committee at two centres. Sarcopenia diagnosis is determined based on low handgrip strength and amount of appendicular skeletal muscle mass, assessed through bioelectrical impedance analysis. Respiratory sarcopenia is diagnosed in patients with sarcopenia who have low inspiratory muscle strength, evaluated through a manovacuometry test. The severity of sarcopenia and respiratory sarcopenia is defined, respectively, by low physical performance (measured using the Short Physical Performance Battery and Timed-Up and Go test) and pulmonary performance (measured through spirometry). Thus, this study will include 81 patients undergoing dialysis (41 on HD and 40 on PD) from three participating centres.

DISCUSSION

The literature has been focused on respiratory function in CKD; however, the relationship with sarcopenia remains understudied. We believe that, similar to appendicular skeleton muscles, the axial skeleton muscles are also likely to weaken with the presence of chronic disease, such as CKD.

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.

One-year impact of COVID-19 pandemic on renal replacement therapy and kidney transplantation in a tertiary center in Southern Brazil

INTRODUCTION

Patients on renal replacement therapy (RRT) and kidney transplant recipients (KTR) present multiple factors that may increase the risk of death from coronavirus disease 2019 (COVID-19). This study aimed to evaluate the incidence and impact of COVID-19 in RRT patients and KTRs.

METHODS

Between March 2020 and February 2021, we monitored the RRT population of thirteen dialysis facilities that refer patients for transplantation to our center, a tertiary hospital in Southern Brazil. In the same period, we also monitor COVID-19 incidence and mortality in our KTR population. Demographical, clinical, and COVID-19-related information were analyzed.

RESULTS

We evaluated 1545 patients in the dialysis centers, of which 267 (17.4%) were infected by COVID-19 and 53 (19.9%) died. Among 275 patients on the kidney transplant waiting list, 63 patients (22.9%) were infected and seven (11.1%) died. COVID-19 was the leading cause of death (29.2%) among patients on the waiting list. Within the population of 1360 KTR, 134 (9.85%) were diagnosed with COVID-19 and 20 (14.9%) died. The number of kidney transplants decreased by 56.7% compared with the same period in the previous twelve months.

CONCLUSION

In the study period, patients on RRT and KTRs presented a high incidence of COVID-19 and high COVID-19-related lethality. The impact on the patients on the transplant waiting list was less pronounced. The lethality rate observed in both cohorts seems to be related to age, comorbidities, and disease severity.

Six-minute walk test may be a reliable predictor of peak oxygen uptake in patients undergoing hemodialysis

Background

Cardiorespiratory fitness seems to play an important role in the general health of patients undergoing hemodialysis (HD). However, the prediction of peak oxygen uptake (V̇O2peak) in a clinical setting is not widely adopted for these patients.

Objectives

Evaluate the agreement and reliability between directly and indirectly V̇O2peak measurements in patients undergoing HD.

Methods

This is a cross-sectional study with patients undergoing HD that performed a cardiopulmonary exercise test (CPET) with 5/10 watts incremental load in each minute using a cycle ergometry to directly evaluate the V̇O2peak, and the 6-min walk test (6MWT) in a 30-m corridor to indirect measures it. Both tests were performed on a midweek non-dialysis day. Bland–Altman analysis of agreement limits was used with direct and indirect V̇O2peak values. Intraclass correlation coefficient (ICC) and Cronbach’s Alpha was used to evaluate the reproducibility and reliability between direct and indirect V̇O2peak values.

Results

Twenty-six patients (54.4 ± 14.5 years, 53.8% of male) were evaluated. The V̇O2peak direct mean obtained through CPET was 15.91 ± 5.26 (ml/kg/min), while the indirect mean obtained through 6MWT was V̇O2peak of 14.89 ± 4.21 (ml/kg/min). There was a strong positive correlation between both V̇O2peak values (r = 0.734; p < 0.001). The Bland–Altman analysis demonstrated that the methods agreed with each other (p = 0.103). Also, the ICC (0.829) and Cronbach's Alpha (0.846) showed excellent reproducibility and reliability.

Conclusions

6MWT is a reliable tool for estimating V̇O2peak in patients undergoing HD.

Censo Brasileiro de Diálise 2021

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.

Impacto de um ano da Pandemia COVID 19 na terapia renal substitutiva e no transplante renal em centro terciário no Sul do Brasil

Resumo Introdução: Pacientes em terapia renal substitutiva (TRS) e receptores de transplante renal (RTR) apresentam múltiplos fatores que podem aumentar o risco de óbito por doença do coronavírus 2019 (COVID-19). Este estudo teve como objetivo avaliar incidência e impacto da COVID-19 em pacientes em TRS e RTR. Métodos: Entre Março de 2020 e Fevereiro de 2021, monitoramos a população em TRS de treze unidades de diálise que encaminham pacientes para transplante ao nosso centro, um hospital terciário no Sul do Brasil. No mesmo período, também monitoramos a incidência e mortalidade da COVID-19 em nossa população de RTR. Foram analisadas informações demográficas, clínicas e relacionadas à COVID-19. Resultados: Avaliamos 1545 pacientes nos centros de diálise, dos quais 267 (17,4%) foram infectados pela COVID-19 e 53 (19,9%) foram a óbito. Entre 275 pacientes na lista de espera para transplante renal, 63 (22,9%) foram infectados e sete (11,1%) foram a óbito. COVID-19 foi a principal causa de óbito (29,2%) entre pacientes na lista de espera. Dentre a população de 1360 RTR, 134 (9,85%) foram diagnosticados com COVID-19 e 20 (14,9%) foram a óbito. O número de transplantes renais diminuiu em 56,7% comparado ao mesmo período nos doze meses anteriores. Conclusão: No período do estudo, pacientes em TRS e RTR apresentaram alta incidência de COVID-19 e alta letalidade relacionada à COVID-19. O impacto nos pacientes na lista de espera para transplante foi menos pronunciado. A taxa de letalidade observada em ambas as coortes parece estar relacionada à idade, comorbidades e gravidade da doença.

Brazilian Dialysis Survey 2020

Introduction:

National data on chronic dialysis treatment are essential to support the development of health policies aimed at improving the treatment for thousands of people.

Objective:

To report epidemiological data from the 2020 Brazilian Dialysis Survey, sponsored by the Brazilian Society of Nephrology.

Methods:

A survey was carried out in Brazilian chronic dialysis centers using an online questionnaire for the year, covering clinical and epidemiological aspects of patients in a chronic dialysis program, data on dialysis therapy, characteristics of dialysis units and the impact of the COVID-19 pandemic.

Results:

235 (28%) of the centers responded to the questionnaire. In July 2020, the estimated total number of patients on dialysis was 144,779. The estimated prevalence and incidence rates of patients per million population (pmp) were 684 and 209, respectively. Of the prevalent patients, 92.6% were on hemodialysis (HD) and 7.4% were on peritoneal dialysis (PD); 23% were on the transplant waiting list. A central venous catheter was used by a quarter of patients on HD. The incidence rate of confirmed COVID-19 between February and July 2020 was 684/10,000 dialysis patients, and the lethality rate was 25.7%. The estimated overall mortality and COVID-19 crude annual mortality rates were 24.5 and 4.2%, respectively.

Conclusion:

The absolute number of patients on chronic dialysis and prevalence rate continued to increase. The low use of PD as dialysis therapy was maintained and the use of long-term catheters for HD increased. The COVID-19 pandemic contributed to the increase in the overall mortality rate.

Brazilian dialysis survey 2019

INTRODUCTION

National data on chronic dialysis treatment are essential for the development of health policies that aim to improve the treatment of patients.

OBJECTIVE

To present data from the Brazilian Dialysis Survey 2019, promoted by the Brazilian Society of Nephrology.

METHODS

Data collection from dialysis units in the country through a completed online questionnaire for 2019.

RESULTS

314 (39%) centers responded the questionnaire. In July 2019, the estimated total number of patients on dialysis was 139,691. Estimates of the prevalence and incidence rates of patients undergoing dialysis treatment per million of the population (pmp) were 665 and 218, respectively, with mean annual increases of 25 pmp and 14 pmp for prevalence and incidence, respectively. The annual gross mortality rate was 18.2%. Of the prevalent patients, 93.2% were on hemodialysis and 6.8% on peritoneal dialysis; and 33,015 (23.6%) on the waiting list for transplantation. 55% of THE centers offered treatment with peritoneal dialysis. Venous catheters were used as access in 24.8% of THE patients on hemodialysis. 17% of the patients had K ≥ 6.0mEq/L; 2.5% required red blood cell transfusion in July 2019 and 10.8% of the patients had serum levels of 25-OH vitamin D < 20 ng/mL.

CONCLUSION

The absolute number of patients, the incidence and prevalence rates in dialysis in the country continue to increase, as well as the percentage of patients using venous catheter as dialysis access. There was an increase in the number of patients on the list for transplantation and a tendency to reduce gross mortality.

Brazilian Dialysis Census: analysis of data from the 2009-2018 decade

INTRODUCTION

National data on chronic dialysis treatment are essential for the development of health policies that aim to improve patient treatment.

OBJECTIVE

To present data from the Brazilian Society of Nephrology on patients with chronic dialysis for kidney disease in July 2018, making a comparative analysis of the past 10 years.

METHODS

Data collection from dialysis units, with filling in an online questionnaire for 2018. Data from 2009, 2013 and 2018 were compared.

RESULTS

288 (36.6%) centers answered the questionnaire. In July 2018, the estimated total number of patients on dialysis was 133,464. Estimates of the prevalence and incidence rates of patients undergoing dialysis treatment per million of the population (pmp) were 640 and 204, respectively, with average annual increases of 23.5 pmp and 6 pmp for prevalence and incidence, respectively. The annual gross mortality rate was 19.5%. Of the prevalent patients, 92.3% were on hemodialysis and 7.7% on peritoneal dialysis, with 29,545 (22.1%) on the waiting list for transplantation. Median bicarbonate concentration in the hemodialysis bath was 32 mEq/L. Venous catheters were used as access in 23.6% of the hemodialysis patients. The prevalence rate of positive serology for hepatitis C showed a progressive reduction (3.2%).

CONCLUSION

The absolute number of patients and rates of incidence and prevalence in dialysis in the country increased substantially in the period, although there are considerable differences in rates by state. There has been a persistent increase in the use of venous catheters as an access for dialysis; and reduction in the number of patients with positive serology for hepatitis C.

Association between severe periodontitis and chronic kidney disease severity in predialytic patients: A cross-sectional study

OBJECTIVE

The aim of this cross-sectional study was to evaluate the association between periodontitis and different severities of chronic kidney disease (CKD) in predialytic patients.

MATERIALS AND METHODS

Demographic, socioeconomic, and medical data of 139 patients from the nephrology service of one university hospital in Porto Alegre, Brazil, were obtained through interview and clinical records. Full-mouth six-sites per tooth periodontal examinations were performed. Associations between periodontitis, stages of CKD, and estimated glomerular filtration rate (eGFR) were estimated by multivariable models adjusted for sex, smoking, vitamin D supplementation, physical activity, and renal treatment duration. CKD was classified based on eGFR (<60 ml/min/1.73 m² ) estimated by the Chronic Kidney Disease Epidemiology Collaboration equation.

RESULTS

Patients with severe periodontitis, compared to those without severe periodontitis, had 2.8 (95% CI: 1.25-6.62) and 3.4 (95% CI: 1.27-9.09) times higher risk of being in stages 4 and 5 of CKD, respectively. Having ≥ 2 teeth with clinical attachment loss (CAL) ≥6 mm increased 3.9 times the risk of being in stage 5 of CKD. Patients with severe periodontitis and ≥2 teeth with CAL ≥ 6 mm had 4.4 ml/min/1.73² and 5.2 ml/min/1.73² lower eGFR (p-values < .05), respectively.

CONCLUSION

Severe periodontitis was associated with poor renal conditions in predialytic CKD patients, strengthening the importance of periodontal evaluation in such patient population.

Brazilian chronic dialysis survey 2017

INTRODUCTION

Having national data on chronic dialysis is essential in treatment planning.

OBJECTIVE

To present data of the survey from the Brazilian Society of Nephrology on patients with chronic kidney disease on dialysis in July 2017.

METHODS

Data was collected from dialysis units in Brazil. The data collection was done using a questionnaire completed online by the dialysis units.

RESULTS

Two hundred and ninety-one centers (38.4%) answered the questionnaire. In July 2017, the estimated total number of dialysis patients was 126,583. National estimates of prevalence and incidence rates of dialysis patients per million population (pmp) were 610 (range: 473 in the North region and 710 in the Midwest) and 194, respectively. The incidence rate of new dialysis patients with diagnosis of diabetic nephropathy was 77 pmp. The annual gross mortality rate was 19.9%. Of the prevalent patients, 93.1% were on hemodialysis and 6.9% on peritoneal dialysis, with 31,226 (24%) on the waiting list for renal transplantation. Venous catheter was used as access in 22.6% of patients on hemodialysis. The prevalence rate of positive serology for hepatitis C continued with a tendency to decrease (3.3%).

CONCLUSION

The absolute number of patients and rates of incidence and prevalence on dialysis continued to increase; the mortality rate tended to rise. There were obvious regional and state discrepancies in these rates.

Brazilian Chronic Dialysis Survey 2016

INTRODUCTION

National chronic dialysis data are important for the treatment planning.

OBJECTIVE

To report data of the annual survey of the Brazilian Society of Nephrology about chronic kidney disease patients on dialysis in July 2016.

METHODS

A survey based on data of dialysis centers from the whole country. The data collection was performed by using a questionnaire filled out on-line by the dialysis centers.

RESULTS

309 (41%) of the dialysis units in the country answered the questionnaire. In July 2016, the total estimated number of patients on dialysis was 122,825. The estimated prevalence and incidence rates of chronic maintenance dialysis were 596 (range: 344 in the North region and 700 in the Southeast) and 193 patients per million of population (pmp), respectively. The annual incidence rate of patients with diabetic nephropathy was 79 pmp. The annual gross mortality rate was 18.2%. For prevalent patients, 92% were on hemodialysis and 8% on peritoneal dialysis, and 29,268 (24%) were on a waiting list of renal transplant. A venous catheter was the vascular access for 20.5% of the hemodialysis patients. The prevalence rates of positive serology for hepatitis B and C showed a tendency to reduce from 2013 (1.4% and 4.2%, respectively) to 2016 (0.7% and 3.7%, respectively).

CONCLUSION

The absolute number and the prevalence and incidence rates of patients on dialysis continue to rise steadily; the gross mortality rate remained stable. Regional inequities are evident in these rates.

Performance of urinary kidney injury molecule-1, neutrophil gelatinase-associated lipocalin, and N-acetyl-β-D-glucosaminidase to predict chronic kidney disease progression and adverse outcomes

Urinary biomarkers can predict the progression of chronic kidney disease (CKD). In this study, kidney injury molecule-1 (KIM-1), neutrophil gelatinase-associated lipocalin (NGAL), and N-acetyl-β-D-glucosaminidase (NAG) were correlated with the stages of CKD, and the association of these biomarkers with CKD progression and adverse outcomes was determined. A total of 250 patients, including 111 on hemodialysis, were studied. Urinary KIM-1, NGAL, and NAG were measured at baseline. Patients not on dialysis at baseline who progressed to a worse CKD stage were compared with those who did not progress. The association of each biomarker and selected covariates with progression to more advanced stages of CKD, end-stage kidney disease, or death was evaluated by Poisson regression. NGAL was moderately correlated (r^s=0.467, P<0.001) with the five stages of CKD; KIM-1 and NAG were also correlated, but weakly. Sixty-four patients (46%) progressed to a more advanced stage of CKD. Compared to non-progressors, those patients exhibited a trend to higher levels of KIM-1 (P=0.064) and NGAL (P=0.065). In patients not on dialysis at baseline, NGAL was independently associated with progression of CKD, ESKD, or death (RR=1.022 for 300 ng/mL intervals; CI=1.007-1.037, P=0.004). In patients on dialysis, for each 300-ng/mL increase in urinary NGAL, there was a 1.3% increase in the risk of death (P=0.039). In conclusion, urinary NGAL was associated with adverse renal outcomes and increased risk of death in this cohort. If baseline urinary KIM-1 and NGAL predict progression to worse stages of CKD is something yet to be explored.

Brazilian Chronic Dialysis Survey 2013 - trend analysis between 2011 and 2013

INTRODUCTION

National chronic dialysis data have had impact in the treatment planning.

OBJECTIVE

To report data of the annual survey of the Brazilian Society of Nephrology about chronic kidney disease patients on dialysis in July 2013 and compare with 2011-12.

METHODS

A survey based on data of dialysis units from the whole country. The data collection was performed by using a questionnaire filled out on-line by the dialysis units.

RESULTS

Three hundred thirty four (51%) of the dialysis units in the country answered the questionnaire. In July 2013, the total estimated number of patients on dialysis was 100,397. The estimated prevalence and incidence rates of chronic maintenance dialysis were 449 (range: 284 in the North region and 622 in the South) and 170 patients per million population, respectively. The estimated number of new patients starting dialysis in 2013 was 34,161. The annual gross mortality rate was 17.9%. For prevalent patients, 31.4% were aged 65 years or older, 90.8% were on hemodialysis and 9.2% on peritoneal dialysis, 31,351 (31.2%) were on a waiting list of renal transplant, 30% were diabetics, 17% had PTH levels > 600 pg/ml and 23% hemoglobin < 10 g/ dl. A venous catheter was the vascular access for 15.4% of the hemodialysis patients.

CONCLUSION

The absolute number of patients on dialysis has increased 3% per year. The prevalence and incidence rates of patients on dialysis leveled off, while the mortality rate tended to decrease compared with 2012. There was a trend towards a better control of the anemia and PTH levels.

[Report of the Brazilian Chronic Dialysis Census 2012]

INTRODUCTION

National chronic dialysis data are fundamental for treatment planning.

OBJECTIVE

To report data of the annual survey of the Brazilian Society of Nephrology about chronic kidney disease patients on dialysis in July 2012.

METHODS

A survey based on data of dialysis units from the whole country. The data collection was performed by using a questionnaire filled out on-line by the dialysis units in Brazil.

RESULTS

255 (31.9%) of the dialysis units in the country answered the questionnaire. In July 2012, the total estimated number of patients on dialysis in the country was 97,586. The estimated prevalence and incidence rates of chronic kidney disease on maintenance dialysis were 503 and 177 patients per million population, respectively. The estimated number of new patients starting dialysis in 2012 was 34,366. The annual gross mortality rate was 18.8%. For prevalent patients, 31.9% were aged 65 years or older, 91.6% were on hemodialysis and 8.4% on peritoneal dialysis, 30,447 (31.2%) were on a waiting list of renal transplant, 28.5% were diabetics, 36.6% had serum phosphorus > 5.5 mg/dl and 34.4% hemoglobin < 11 g/dl. A venous catheter was the vascular access for 14.5% of the hemodialysis patients.

CONCLUSION

The prevalence and incidence rates of chronic kidney disease patients on dialysis increased, while the mortality rate tended to decrease compared with 2011. The indicators of the quality of maintenance dialysis remained stable with a trend towards decrease in levels of anemia. The data highlight the importance of the census to guide chronic dialysis therapy.

Brazilian Chronic Dialysis Survey 2013 - trend analysis between 2011 and 2013

INTRODUCTION

National chronic dialysis data have had impact in the treatment planning.

OBJECTIVE

To report data of the annual survey of the Brazilian Society of Nephrology about chronic kidney disease patients on dialysis in July 2013 and compare with 2011-12.

METHODS

A survey based on data of dialysis units from the whole country. The data collection was performed by using a questionnaire filled out on-line by the dialysis units.

RESULTS

Three hundred thirty four (51%) of the dialysis units in the country answered the questionnaire. In July 2013, the total estimated number of patients on dialysis was 100,397. The estimated prevalence and incidence rates of chronic maintenance dialysis were 449 (range: 284 in the North region and 622 in the South) and 170 patients per million population, respectively. The estimated number of new patients starting dialysis in 2013 was 34,161. The annual gross mortality rate was 17.9%. For prevalent patients, 31.4% were aged 65 years or older, 90.8% were on hemodialysis and 9.2% on peritoneal dialysis, 31,351 (31.2%) were on a waiting list of renal transplant, 30% were diabetics, 17% had PTH levels > 600 pg/ml and 23% hemoglobin < 10 g/ dl. A venous catheter was the vascular access for 15.4% of the hemodialysis patients.

CONCLUSION

The absolute number of patients on dialysis has increased 3% per year. The prevalence and incidence rates of patients on dialysis leveled off, while the mortality rate tended to decrease compared with 2012. There was a trend towards a better control of the anemia and PTH levels.

[Effects of aerobic exercise during haemodialysis in patients with chronic renal disease: a literature review]

INTRODUCTION

Patients with chronic kidney disease (CKD) have reduced physical and functional capacity when compared with the general population. Hemodialysis (HD) restricts patients activities, favoring a sedentary lifestyle and leading to functional limitations. HD patients are less active, present low exercise tolerance and have high physical deconditioning. Physical exercise programs have been proposed as a strategy not only to treat clinical symptoms, but also to reduce physical limitations and improve the quality of life of these patients.

OBJECTIVES

The purpose of this study was to review the literature on the effects of physical exercise (aerobic exercise on a cycle ergometer for the lower limbs) on CKD undergoing HD.

METHODS

The Medline, PubMed, Scielo, Embase and DirectScience databases were searched.

RESULTS

Fourteen randomized controlled clinical trials were analyzed as regards the timing of the intervention during the HD session, exercise intensity and frequency, the duration of the intervention and the main results.

CONCLUSION

The studies demonstrated that aerobic exercises performed during HD improve the aerobic capacity and physical conditioning, reduce fatigue and anxiety, improve muscle capillarization and resting blood pressure, increase exercise duration and improve urea clearance.

[Chronic dialysis in Brazil: report of the Brazilian dialysis census, 2011]

INTRODUCTION

National data on maintenance dialysis are important for treatment planning.

AIM

To describe the results of the dialysis census of the Brazilian Society of Nephrology for 2011 and observed trends from 2000 to 2011.

METHODS

A survey was conducted using questionnaire filled online by the dialysis units, with July as reference month for estimates. From a total of 645 units, 353 (54.9%) responded to the survey.

RESULTS

The estimated number of patients on dialysis in Brazil was 91,314 in 2011 (42,629 in 2010; 92,091 in 2011). For approximately 85% of the patients the treatment was provided by the Brazilian Unified Health Care System. The estimated prevalence and incidence rates in 2011 were 475 and 149 maintenance dialysis patients per million population, respectively. For prevalent patients, 90.6% were on hemodialysis, 31.5% 65 years of age or older, 28% diabetic and 35.5% (n=32,454) on waiting list for transplantation in 2011. The estimated number of patients starting dialysis in 2011 was 28,680 (18,972 in 2010) and annual mortality rate 19.9% (17.9% in 2010).

CONCLUSIONS

The data indicate pronounced increase in the dialysis population across the years in Brazil with a trend for stabilization in the last two years. The reason for the increase in incidence and mortality in 2011 deserves investigation. A large number of patients were on waiting list for renal transplantation. By providing a picture of the situation and trends on maintenance dialysis treatment in Brazil the census is useful to guide resources allocation and interventions to improve treatment quality.

Malnourished patients on hemodialysis improve after receiving a nutritional intervention

INTRODUCTION

Malnutrition is multifactorial and may be modified by nutritional intervention. We aimed to assess the impact of an intervention on the nutritional status of malnourished hemodialysis patients and their acceptance of a non-industrialized nutritional supplement.

METHODS

18 patients were studied, they were selected from a previous nutritional assessment where nutritional risk was defined as: subjective global assessment > 15 plus one criterion for malnutrition. The following variables were assessed: anthropometric parameters, subjective global assessment, dietary intake, six-minute walking test, quality of life (SF-36), and biochemical tests. Patients were randomized to either Control or Intervention Groups. The Intervention Group received a dietetic supplement during dialysis containing 355 kcal, prepared from simple ingredients. After three months, subjects from the Control Group and other patients also considered at nutritional risk underwent the same intervention. The study groups were compared after three months, and all patients were analyzed before and after the intervention.

RESULTS

Fifteen men and three women, aged 56.4 ± 15.6 years-old, nine in each group, were studied. The Intervention Group showed an improvement in the subjective global assessment (p = 0.04). There were differences in role physical and bodily pain domains of SF-36, with improvement in the Intervention Group and worsening in the Control Group (p = 0.034 and p = 0.021). Comparisons before and after intervention for all patients showed improvement in the subjective global assessment (16.18 ± 4.27 versus 14.37 ± 4.20, p = 0.04), and in the six-minute walking test (496.60 ± 132.59 versus 547.80 ± 132.48 m; p = 0.036). The nutritional supplement was well tolerated by all patients, and it did not cause side effects.

CONCLUSIONS

The nutritional intervention improved the subjective global assessment and quality of life of hemodialysis patients at short-term. A global intervention by a dietitian produced specific and nonspecific positive effects in the whole group. Nutritional supplementation was feasible, palatable, and had low cost. Its clinical impact and effectiveness need to be further assessed in a larger group of patients at long-term.

2010 report of the Brazilian dialysis census

INTRODUCTION

National chronic dialysis data are fundamental for treatment planning.

OBJECTIVE

To report data of the annual survey of the Brazilian Society of Nephrology about patients with chronic renal failure who were on dialysis in 1 July, 2010.

METHODS

A national survey based on data from the country's dialysis centers. Data collection was performed by using a questionnaire filled out online by the dialysis centers.

RESULTS

340 (53.3%) centers answered the questionnaire. National data were estimated for the overall dialysis population. In July 2010, the estimated total number of patients on dialysis was 92,091. The estimated prevalence and incidence rates of end-stage chronic kidney disease patients on maintenance dialysis were 483 and 100/million population, respectively. The estimated number of patients starting a dialysis program in 2010 was 18,972. The annual crude mortality rate was 17.9%. Of those on maintenance dialysis, 30.7% were aged 65 years or older, 90.6% were on hemodialysis and 9.4% on peritoneal dialysis, 35,639 (38.7%) were on a kidney transplant waiting list, 28% were diabetics, 34.5% had serum phosphorus levels > 5.5 mg/dL, and 38.5% had hemoglobin levels < 11 g/dL. Vascular access was through a venous catheter in 13.6% of the hemodialysis patients.

CONCLUSIONS

The number of end-stage kidney disease patients on maintenance dialysis is increasing in Brazil. Data concerning the indicators of the quality of maintenance dialysis improved compared to the prior year, and they highlight the importance of the census to guide chronic dialysis therapy.

Brazilian dialysis census, 2009

INTRODUCTION

National dialysis data are fundamental for treatment planning.

OBJECTIVE

To report data of the annual survey of the Brazilian Society of Nephrology about chronic renal failure patients on dialysis in January 2009.

METHODS

A survey based on data of dialysis units from the whole country. The data collection was performed by using a questionnaire filled out by the dialysis units in Brazil.

RESULTS

427 (69.8%) of the dialysis units in the country answered the questionnaire. National data were estimated for the overall dialysis population. In January 2009, the total estimated number of patients on dialysis was 77,589. The estimated prevalence and incidence rates of chronic renal failure on maintenance dialysis were 405 and 144 patients per million population, respectively. The estimated number of new patients starting dialysis program in 2009 was 27,612. The annual gross mortality rate was 17.1%. For prevalent patients, 39.9% were aged 60 years or older, 89.6% were on hemodialysis and 10.4% on peritoneal dialysis, 30,419 (39.2%) were on a waiting list of renal transplant, 27% were diabetics, 37.9% had serum phosphorus > 5.5 mg/dL and 42.8% hemoglobin < 11 g/dL. A venous catheter was the vascular access for 12.4% of the hemodialysis patients.

CONCLUSIONS

The prevalence of chronic renal failure on maintenance dialysis is increasing in Brazil, although in 2009 the estimate is lower than in 2008. The data call attention to indicators of the quality of maintenance dialysis that need to be improved and highlight the importance of the census to guide chronic dialysis therapy.

Enoxaparin versus unfractioned heparin as anticoagulant for continuous venovenous hemodialysis: a randomized open-label trial

AIM

In this study we aimed to compare the efficacy and safety of enoxaparin with unfractioned heparin (UFH) as anticoagulant for continuous venovenous hemodialysis (CVVHD).

METHODS

An open-label randomized controlled trial was carried out in an intensive care unit (ICU) where 40 patients with acute renal failure (ARF) who needed continuous renal replacement therapy were randomized to receive UFH (n=21) or enoxaparin (n=19). Coagulation parameters were evaluated, and antithrombotic activity of UFH was measured by activated partial thromboplastin time (aPTT) and for enoxaparin by anti-factor Xa activity. Primary outcomes were thrombosis of the extracorporeal circuit and bleeding, classified as major or minor.

RESULTS

Minor bleeding episodes were observed only in patients anticoagulated with enoxaparin (26 vs. 0%, p=0.018). Comparing patients with or without bleeding after 24 hours of therapy, the level of anticoagulation tended to be higher (anti-factor Xa: 1.62 vs. 1.13 IU/mL, p=0.09) and the platelet count to be lower [107+/-53 vs. 229+/-84 (x10(3)/microL), p=0.09] in patients who bled, but without statistical difference. Filter life span of enoxaparin and UFH groups was similar (43+/-15 vs. 52+/-18 hr, p=0.10), as well as the proportion of circuit clotting.

CONCLUSION

Weight-unadjusted enoxaparin in patients with ARF in CVVHD was associated with an increased rate of bleeding, a finding that addresses the need to adjust drug dose and to monitor anti-factor Xa activity during dialysis. No benefit to prolong dialysis circuit survival was found with enoxaparin. In patients who do not present contraindication for systemic anticoagulation, UFH remains an effective and low-cost option.

Dialysis water treated by reverse osmosis decreases the levels of C-reactive protein in uremic patients

Atherosclerosis is a major complication of chronic renal failure. Microinflammation is involved in atherogenesis and is associated with uremia and dialysis. The role of dialysate water contamination in inducing inflammation has been debated. Our aim was to study inflammatory markers in patients on chronic dialysis, before and 3 to 6 months after switching the water purification system from deionization to reverse osmosis. Patients had demographic, clinical and nutritional information collected and blood drawn for determination of albumin, ferritin, C-reactive protein (CRP), interleukin-6, and tumor necrosis factor-alpha in both situations. Acceptable levels of water purity were less than 200 colony-forming units of bacteria and less than 1 ng/ml of endotoxin. Sixteen patients died. They had higher median CRP (26.6 vs 11.2 mg/dl, P = 0.007) and lower median albumin levels (3.1 vs 3.9 g/l, P < 0.05) compared to the 31 survivors. Eight patients were excluded because of obvious inflammatory conditions. From the 23 remaining patients (mean age +/- SD: 51.3 +/- 13.9 years), 18 had a decrease in CRP after the water treatment system was changed. Overall, median CRP was lower with reverse osmosis than with deionization (13.2 vs 4.5 mg/l, P = 0.022, N = 23). There was no difference in albumin, cytokines, subjective global evaluation, or clinical and biochemical parameters. In conclusion, uremic patients presented a clinically significant reduction in CRP levels when dialysate water purification system switched from deionization to reverse osmosis. It is possible that better water treatments induce less inflammation and eventually less atherosclerosis in hemodialysis patients.

[Increased skin pigmentation in patients with chronic renal failure undergoing hemodialysis infected with the hepatitis C virus]

BACKGROUND

Skin pigmentation is commonly found in patients with chronic renal failure (CRF). This symptom is also one of the most evident features of Porphyria Cutanea Tarda (PCT). Hepatitis C virus (HCV) is an important precipitating agent of this disease, which has been described in patients undergoing hemodialysis (HD). In this paper, we intend to evaluate the prevalence of difuse skin hyperpigmentation in patients with CRF infected with the HCV.

METHODS

We developed a transversal study with 47 patients (mean age 50,35 + 15,16 years; 31 men and 16 women) who were on hemodialysis in march of 2001 at the Unit of Dialysis of Hospital de Cl nicas de Porto Alegre. Patients were divided in two groups: group 1, anti-HCV positives (n=17), and group 2, anti-HCV negatives (n=30).

RESULTS

The prevalence of skin hyperpigmentation related to HD was 36,2% (n=17). There were 10 patients (58,8%) in group 1 and 7 (23,3%) in group 2 (Odds Ratio of 2,52 and 95% Confidence Interval of 1,18-5,4; p<0,05). Among patients who have undergone HD for until 36 months (n=24), 6 were anti-HCV positive and 3 of tham (50%) mentioned skin pigmentation (OR of 9,0 and 95%CI of 1,1-71,0; p<0,05). Patients from group 2 who referenced the symptom have been on HD for a longer period than those who did not (63,85 + 11,9 vs. 29,3 + 4,71 months; p<0,05).

CONCLUSIONS

HCV infection was associated with increased skin hyperpigmentation in patients with CRF undergoing HD. Time on treatment was also associated with this signal.

CAPD in southern Brazil: an epidemiological study

There are many studies on the performance of continuous ambulatory peritoneal dialysis (CAPD) in developed countries, but studies in the third world are scarce. The aim of this study is to analyze CAPD experience in the southernmost state of Brazil (Rio Grande do Sul, RS). Records were obtained from the Health Secretary of RS to assemble a cohort of all patients treated with CAPD. Another cohort study followed all patients initiating treatment for uremia in 1993 in the state capital, Porto Alegre, and compared CAPD, hemodialysis, and transplanted patients. In RS, 1316 patients (50.4% male, mean age 45.9 years) were treated in 40 CAPD programs. Despite the initial growth of the CAPD population, it subsequently leveled off. Survival was 78.6% and 40.7% in years 1 and 5, being worse for initial patients of each program, infants, and elders. Technique survival was 57.4% and 10.1% at years 1 and 5. Patients interrupting treatment for any reason had a higher chance of dropout. In Porto Alegre, 294 patients started dialysis during 1993; 21 performed CAPD, 44 had a transplant, and the others were hemodialyzed. Children were treated mostly by CAPD. CAPD patients had less diabetes and ischemic heart disease and received more transplants. Their adjusted actuarial survival (100% year 1; 67% year 3) was no different than hemodialysis. CAPD is not a popular form of renal therapy in RS, and dropout rates are significant.

Vascular angiotensin II receptors in SHR

We investigated the density (Bmax) of angiotensin II (ANG II) receptors in the mesenteric vascular bed of spontaneously hypertensive rats (SHR) and age-matched Wistar-Kyoto (WKY) control rats. In 12-week-old SHR, the Bmax and the dissociation constant (Kd) of ANG II binding sites were not different from those of WKY rats in the sodium replete state or after sodium depletion. In prehypertensive (4- and 6-week-old) SHR, the Bmax of the vascular ANG II receptors was significantly higher (p less than 0.05) than in age-matched WKY rats. This result could not be attributed entirely to differences in the circulating renin-angiotensin-aldosterone system in 4-week-old-rats. In 6-week-old WKY rats, the plasma renin activity was significantly higher (p less than 0.05), which may account in part for the higher density of ANG II binding sites in SHR. There was an age-related decrease in the number of ANG II receptors in SHR. The increased density of vascular ANG II receptors in young SHR may play a role in the development of high blood pressure in this model of spontaneous hypertension. The higher number of ANG II binding sites in young SHR is not selective for ANG II receptors, since an increased density of alpha 1-adrenergic receptors was also found in the mesenteric arteries of 4-week-old SHR.

Vascular angiotensin II receptors in renal and DOCA-salt hypertensive rats

To determine the contribution of receptor number and affinity to changes in vascular reactivity to angiotensin II (AII) in hypertensive rats, we have investigated the binding of 125I-AII to a particulate fraction of the rat mesenteric artery of hypertensive rats. In two-kidney, one clip hypertensive rats, receptor concentration (Bmax) was 83 +/- 13 fmol/mg and the dissociation constant (Kd) 0.6 +/- 0.1 nM vs 75 +/- 5.3 fmol/mg and 0.6 +/- 0.1 nM in normotensive controls, although PRA was much higher in the former. Bmax was reduced in these hypertensive rats after sodium depletion, as in normal rats. One-kidney, one clip hypertensive rats (Bmax 88 +/- 17 fmol/mg, Kd 0.6 +/- 0.1 nM) did not differ from uninephrectomized control rats (96 +/- 9 fmol/mg, Kd 0.5 +/- 0.1 nM). In DOCA-salt hypertensive rats, binding capacity was increased (125 +/- 2 fmol/mg, Kd 0.7 +/- 0.0 nM) vs uninephrectomized salt-loaded rats (Bmax 95 +/- 6 fmol/mg, Kd 0.6 +/- 0.1 nM), although PRA was suppressed comparably in both groups. The salt-loaded rats did not differ from uninephrectomized controls drinking water. We conclude that changes in the circulating renin-angiotensin system do not explain all the variations in receptor number in hypertensive rats. Our results suggest a role of mineralocorticoids in the regulation of vascular AII receptors.