RESUMO
INTRODUCTION: The associations of kidney-metabolic biomarkers with cognitive impairment (CI) beyond the estimated glomerular filtration rate (eGFR, in mL/min/1.73 m2) and albuminuria levels are not well understood. In exploratory analysis, our objective was to determine the extent that three kidney-metabolic factors, previously proposed as mechanisms of CI and commonly abnormal in chronic kidney disease (CKD), were associated with prevalent CI in CKD participants, adjusted for kidney function measures. METHODS: The study cohort included community-dwelling individuals aged ≥45 years with CKD (eGFR <60), not requiring dialysis, recruited from four health systems. We examined the serum biomarkers bicarbonate (CO2), TNFαR1, and cholesterol as primary exposures. A structured neuropsychological battery conducted by trained staff measured global and domain-specific cognitive performance. Logistic regression analyses estimated the cross-sectional associations between kidney-metabolic measures and global and cognitive domain-specific moderate/severe (Mod/Sev) CI, adjusted for the eGFR, urinary albumin-creatinine ratio (UACR, mg/g), demographics, comorbid conditions, and other kidney-metabolic biomarkers commonly abnormal in CKD. RESULTS: Among 436 CKD participants with mean age 70 years, 16% were Black, the mean eGFR was 34, and the median [IQR] UACR was 49 [0.0, 378] mg/g. In adjusted models, increased TNFαR1 was associated with global Mod/Sev CI (odds ratio [95% confidence interval] = 1.40 [1.02, 1.93]; p = 0.04); low bicarbonate (CO2 <20 mEq/L) with Mod/Sev memory impairment (3.04 [1.09, 8.47]; p = 0.03), and each 10-mg/dL lower cholesterol was associated with Mod/Sev executive function/processing speed impairment (1.12 [1.02, 1.23]; p = 0.02). However, after adjustment for multiple comparisons, these associations were no longer significant nor were any other kidney-metabolic factors significant for any CI classification. CONCLUSION: In exploratory analyses in a CKD population, three kidney-metabolic factors were associated with CI, but after adjustment for multiple comparisons, were no longer significant. Future studies in larger CKD populations are needed to assess these potential risk factors for CI.
Assuntos
Disfunção Cognitiva , Insuficiência Renal Crônica , Idoso , Albuminúria/epidemiologia , Bicarbonatos , Dióxido de Carbono , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/etiologia , Estudos Transversais , Taxa de Filtração Glomerular , Humanos , Rim , Projetos Piloto , Fatores de RiscoRESUMO
BACKGROUND: Ultrafiltration rate (UFR) has attracted attention as a modifiable aspect of volume management. OBJECTIVE: The objective of this review is to summarize the evidence that links UFR to patient outcomes and discuss UFR cut-offs proposed, and discuss possible consequences of adapting UFR as a quality metric. RESULTS: Higher UFRs has been associated with younger age, longer dialysis vintage, greater prevalence of comorbidities, higher Kt/V, lower weight, greater interdialytic weight gain, lower residual renal function, and shorter treatment times. Many of the characteristics associated with high UFRs have also been independently associated with poor patient outcomes. Four observational studies have assessed the association between UFR and patient mortality. All of them reported an association between higher UFR and greater patient mortality, though the studies differed in their definition of UFR, follow-up, and adjustment for confounding. Evidence for the association between higher UFR and potential mediations of the mortality association, such as interdialytic hypotension, cardiac remodeling, and cardiovascular events was less consistent. There was a graded association between higher UFRs and all-cause mortality; no definitive cut-off for acceptable UFR can be established based on the current evidence. Targeting UFR in isolation might result in volume expansion and worsening patient outcomes. Residual confounding likely contributed to the findings of the observational studies. No randomized controlled trials addressed the questions. CONCLUSION: Evidence supporting UFR limits is weak and confounded. Randomized controlled trials are needed before UFR can be used as a quality of care indicator.
Assuntos
Hemodiafiltração/métodos , Falência Renal Crônica/terapia , Feminino , Hemodiafiltração/efeitos adversos , Hemodiafiltração/mortalidade , Humanos , Falência Renal Crônica/mortalidade , Masculino , Melhoria de Qualidade , Fatores de Risco , Taxa de Sobrevida , Resultado do TratamentoRESUMO
OBJECTIVE: Determine whether serum phosphate is associated with concurrent cognitive impairment and subsequent cognitive decline in older men independent of demographic covariates and atherosclerotic risk factors. METHODS: In a prospective study of 5529 men enrolled in the Osteoporotic Fractures in Men study, we measured baseline serum phosphate, baseline cognitive function, and change in cognitive function between baseline and follow-up exams an average of 4.6 years later using the Modified Mini-Mental State (3MS) Examination and Trails B. RESULTS: There was no association between serum phosphate and odds of cognitive impairment as assessed by baseline 3MS score or risk of cognitive decline as assessed by longitudinal change in 3MS score. Higher baseline serum phosphate was associated with higher odds of poor executive function as assessed by Trails B with fully adjusted odds ratios 1.12 (95% confidence interval: 0.83-1.52), 1.31 (0.97-1.77), and 1.45 (1.08-1.94) for men in the second, third, and fourth versus the bottom quartile (referent group) of serum phosphate (p-trend 0.007). However, higher phosphate level was not associated with risk of decline in executive function as assessed by longitudinal change in Trails B score with fully adjusted odds ratios 0.94 (95% confidence interval 0.69-1.28), 0.96 (0.70-1.32), and 1.21 (0.89-1.66) for men in the second, third, and fourth versus the bottom quartile (referent group) of serum phosphate (p-trend 0.22). CONCLUSIONS: Higher serum phosphate in older men was associated with a higher likelihood of poor executive function, but not with impaired global cognitive function or decline in executive or global cognition. Copyright © 2017 John Wiley & Sons, Ltd.
Assuntos
Transtornos Cognitivos/sangue , Cognição/fisiologia , Fosfatos/sangue , Idoso , Idoso de 80 Anos ou mais , Transtornos Cognitivos/fisiopatologia , Função Executiva , Feminino , Humanos , Masculino , Razão de Chances , Estudos Prospectivos , Fatores de RiscoRESUMO
BACKGROUND: Chronic kidney disease is common and is associated with cardiovascular disease, cerebrovascular disease, and cognitive function, although the nature of this relationship remains uncertain. STUDY DESIGN: Cross-sectional cohort using baseline data from the Systolic Blood Pressure Intervention Trial (SPRINT). SETTING & PARTICIPANTS: Participants in SPRINT, a randomized clinical trial of blood pressure targets in older community-dwelling adults with cardiovascular disease, chronic kidney disease, or high cardiovascular disease risk and without diabetes or known stroke, who underwent detailed neurocognitive testing in the cognition substudy, SPRINT-Memory and Cognition in Decreased Hypertension (SPRINT-MIND). PREDICTORS: Urine albumin-creatinine ratio (ACR) and estimated glomerular filtration rate (eGFR). OUTCOMES: Cognitive function, a priori defined as 5 cognitive domains based on 11 cognitive tests using z scores, and abnormal white matter volume quantified by brain magnetic resonance imaging. RESULTS: Of 9,361 SPRINT participants, 2,800 participated in SPRINT-MIND and 2,707 had complete data; 637 had brain imaging. Mean age was 68 years, 37% were women, 30% were black, and 20% had known cardiovascular disease. Mean eGFR was 70.8±20.9mL/min/1.73m2 and median urine ACR was 9.7 (IQR, 5.7-22.5) mg/g. In adjusted analyses, higher ACR was associated with worse global cognitive function, executive function, memory, and attention, such that each doubling of urine ACR had the same association with cognitive performance as being 7, 10, 6, and 14 months older, respectively. Lower eGFR was independently associated with worse global cognitive function and memory. In adjusted models, higher ACR, but not eGFR, was associated with larger abnormal white matter volume. LIMITATIONS: Cross-sectional only, no patients with diabetes were included. CONCLUSIONS: In older adults, higher urine ACR and lower eGFR have independent associations with global cognitive performance with different affected domains. Albuminuria concurrently identifies a higher burden of abnormal brain white matter disease, suggesting that vascular disease may mediate these relationships.
Assuntos
Transtornos Cognitivos , Cognição/fisiologia , Insuficiência Renal Crônica , Idoso , Determinação da Pressão Arterial/métodos , Doenças Cardiovasculares/epidemiologia , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/fisiopatologia , Estudos Transversais , Feminino , Taxa de Filtração Glomerular , Humanos , Hipertensão/diagnóstico , Hipertensão/psicologia , Testes de Inteligência , Testes de Função Renal/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/psicologia , Fatores de Risco , Estatística como Assunto , Substância Branca/diagnóstico por imagemRESUMO
BACKGROUND: The Brain in Kidney Disease (BRINK) Study aims to identify mechanisms that contribute to increased risk for cognitive impairment in patients with chronic kidney disease (CKD). We describe the rationale, design, and methods of the study and report baseline recruitment and cognitive function results. STUDY DESIGN: Longitudinal observational cohort study of the epidemiology of cognitive impairment in CKD. The primary aim is to characterize the association between (1) baseline and incident stroke, white matter disease, estimated glomerular filtration rate (eGFR), inflammation, microalbuminuria, and dialysis initiation and (2) cognitive decline over 3 years in a CKD cohort with a mean eGFR<45 mL/min/1.73 m(2). SETTING & PARTICIPANTS: Community-dwelling participants 45 years or older recruited from 4 health systems into 2 groups: reduced eGFR, defined as eGFR<60 mL/min/1.73 m(2) (non-dialysis dependent), and control, defined as eGFR≥60 mL/min/1.73 m(2). PREDICTOR: eGFR group. OUTCOMES: Performance on cognitive function tests and structural brain magnetic resonance imaging. MEASUREMENTS: Sequential cognitive and physical function testing, serum and urine biomarker measurement, and brain magnetic resonance images over 3 years. RESULTS: Of 554 participants, mean age was 69.3 years; 333, 88, and 133 had eGFRs<45 (non-dialysis dependent, nontransplantation), 45 to <60, and ≥60 (controls) mL/min/1.73 m(2), respectively. Mean eGFR in reduced-eGFR participants was 34.3 mL/min/1.73 m(2). Baseline cognitive performance was significantly associated with eGFR in all domains except language. Participants with eGFRs<30 mL/min/1.73 m(2) performed significantly worse than those with eGFRs≥30 mL/min/1.73 m(2) on tests of memory, processing speed, and executive function. Participants with reduced eGFRs overall scored worst on the Immediate Brief Visual-Spatial Memory Test-Revised. LIMITATIONS: Healthy cohort bias, competing risk for death versus cognitive decline. CONCLUSIONS: Cognitive function was significantly worse in participants with eGFRs<30 mL/min/1.73 m(2). Future BRINK analyses will measure risk factors for cognitive decline using the longitudinal data.
Assuntos
Transtornos Cognitivos/etiologia , Insuficiência Renal Crônica/complicações , Idoso , Cognição , Transtornos Cognitivos/epidemiologia , Estudos de Coortes , Feminino , Taxa de Filtração Glomerular , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Insuficiência Renal Crônica/fisiopatologia , Insuficiência Renal Crônica/psicologia , Projetos de PesquisaRESUMO
BACKGROUND: In 2006, NKF-KDOQI (National Kidney Foundation-Kidney Disease Outcomes Quality Initiative) published clinical practice guidelines for hemodialysis adequacy. Recent studies evaluating hemodialysis adequacy as determined by initiation timing, frequency, duration, and membrane type and prompted an update to the guideline. STUDY DESIGN: Systematic review and evidence synthesis. SETTING & POPULATION: Patients with advanced chronic kidney disease receiving hemodialysis. SELECTION CRITERIA FOR STUDIES: We screened publications from 2000 to March 2014, systematic reviews, and references and consulted the NKF-KDOQI Hemodialysis Adequacy Work Group members. We included randomized or controlled clinical trials in patients undergoing long-term hemodialysis if they reported outcomes of interest. INTERVENTIONS: Early versus late dialysis therapy initiation; more frequent (>3 times a week) or longer duration (>4.5 hours) compared to conventional hemodialysis; low- versus high-flux dialyzer membranes. OUTCOMES: All-cause and cardiovascular mortality, myocardial infarction, stroke, hospitalizations, quality of life, depression or cognitive function scores, blood pressure, number of antihypertensive medications, left ventricular mass, interdialytic weight gain, and harms or complications related to vascular access or the process of dialysis. RESULTS: We included 32 articles reporting on 19 trials. Moderate-quality evidence indicated that earlier dialysis therapy initiation (at estimated creatinine clearance [eClcr] of 10-14mL/min) did not reduce mortality compared to later initiation (eClcr of 5-7mL/min). More than thrice-weekly hemodialysis and extended-length hemodialysis during a short follow-up did not improve clinical outcomes compared to conventional hemodialysis and resulted in a greater number of vascular access procedures (very low-quality evidence). Hemodialysis using high-flux membranes did not reduce all-cause mortality, but reduced cardiovascular mortality compared to hemodialysis using low-flux membranes (moderate-quality evidence). LIMITATIONS: Few studies were adequately powered to evaluate mortality. Heterogeneity of study designs and interventions precluded pooling data for most outcomes. CONCLUSIONS: Limited data indicate that earlier dialysis therapy initiation and more frequent and longer hemodialysis did not improve clinical outcomes compared to conventional hemodialysis.
Assuntos
Falência Renal Crônica/terapia , Guias de Prática Clínica como Assunto , Diálise Renal/métodos , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/mortalidade , Depressão/epidemiologia , Intervenção Médica Precoce , Hospitalização/estatística & dados numéricos , Humanos , Falência Renal Crônica/mortalidade , Infarto do Miocárdio/epidemiologia , Qualidade de Vida , Acidente Vascular Cerebral/epidemiologia , Fatores de Tempo , Resultado do TratamentoRESUMO
BACKGROUND/AIMS: Physician characteristics are associated with differential performance on quality measures and patient outcomes in several medical fields. We aimed to determine whether characteristics of physicians who provide care to dialysis patients were associated with patient outcomes. METHODS: This cohort study used United States Renal Data System data for patients who initiated in-center hemodialysis between October 1, 2003, and September 30, 2006 (n = 91,276). Patient characteristics were defined and physicians identified from Part B Medicare claims for outpatient dialysis services submitted during months 4-6 of hemodialysis. Physician characteristics were obtained from the American Medical Association Physician Master File. Associations of physician characteristics with 1-year patient mortality and first hospitalization were determined using Cox proportional hazards analysis; associations with quality of care (defined by influenza vaccination and waitlisting for kidney transplant) were determined using logistic regression. RESULTS: Physician characteristics were not associated with patient mortality. After adjustment for patient and other provider characteristics, patients whose physicians had practiced longer or were in administrative, research, or teaching practices were more likely to be hospitalized; patients whose providers practiced in smaller metropolitan statistical areas (MSAs) were less likely. More years since training was associated with greater chance of waitlisting, and practicing in smaller MSAs with less chance. Graduation from a foreign medical school, practicing in smaller MSAs, and travelling farther from office to dialysis unit were associated with greater odds of influenza vaccination. CONCLUSIONS: Several characteristics of physicians seeing incident outpatient hemodialysis patients were associated with hospitalization and quality of care, but none with mortality.
Assuntos
Hospitalização/estatística & dados numéricos , Falência Renal Crônica/mortalidade , Falência Renal Crônica/terapia , Nefrologia/estatística & dados numéricos , Qualidade da Assistência à Saúde , Diálise Renal/estatística & dados numéricos , Adulto , Idoso , Área Programática de Saúde/estatística & dados numéricos , Competência Clínica/estatística & dados numéricos , Estudos de Coortes , Bases de Dados Factuais , Educação Médica/estatística & dados numéricos , Docentes de Medicina/estatística & dados numéricos , Feminino , Médicos Graduados Estrangeiros/estatística & dados numéricos , Humanos , Influenza Humana/prevenção & controle , Transplante de Rim , Masculino , Pessoa de Meia-Idade , Nefrologia/normas , Diálise Renal/mortalidade , Diálise Renal/normas , Fatores de Risco , Fatores de Tempo , Estados Unidos , Vacinação/estatística & dados numéricos , Listas de Espera , Adulto JovemRESUMO
BACKGROUND/AIMS: In 2004, the Centers for Medicare and Medicaid Services tied reimbursement for outpatient hemodialysis services to the number of times per month providers see their dialysis patients, resulting in increased provider-patient visit frequency. Greater provider-patient visit frequency is associated with lower hospitalization risk for hemodialysis patients, and determinants of visit frequency are uncertain. We aimed to identify patient, provider, and dialysis facility characteristics associated with provider visit frequency. METHODS: This retrospective cohort study used United States Renal Data System (USRDS) data for point-prevalent patients receiving in-center hemodialysis on January 1, 2006 (n = 144,860). Patient characteristics were defined from January 1 to June 30, 2006, and provider-patient visit frequency (<4 vs. ≥4 visits/month) from July 1 to December 31, 2006. Patient characteristics were obtained from the USRDS. Provider data were obtained from the American Medical Association Physician Master File. We determined longitudinal associations between patient, provider, and facility characteristics and provider-patient visit frequency using logistic regression. RESULTS: Patient characteristics independently associated with greater provider-patient visit frequency included older age, African-American race, longer dialysis duration, higher comorbidity score, Medicaid eligibility, urban residence, better compliance with dialysis, and more hospital days during run-in. Provider characteristics associated with greater provider-patient visit frequency included more years in practice, graduation from a foreign medical school, shorter distance between provider office and dialysis unit, and caring for more dialysis patients; facility characteristics included free-standing, independent status. CONCLUSION: After the Medicare reimbursement policy change, several patient, provider, and facility characteristics were independently associated with greater dialysis provider-patient visit frequency.
Assuntos
Falência Renal Crônica/terapia , Diálise Renal/métodos , Diálise Renal/estatística & dados numéricos , Adulto , Idoso , Assistência Ambulatorial/métodos , Instituições de Assistência Ambulatorial , Centers for Medicare and Medicaid Services, U.S. , Comorbidade , Bases de Dados Factuais , Feminino , Humanos , Falência Renal Crônica/etnologia , Masculino , Pessoa de Meia-Idade , Padrões de Prática Médica , Relações Profissional-Paciente , Estudos Retrospectivos , Estados Unidos , Adulto JovemRESUMO
In January of 2004, the Centers for Medicare & Medicaid Services tied provider reimbursement for outpatient hemodialysis services to the number of provider-patient visits per month. We aimed to determine whether greater visit frequency associated with lower mortality and hospitalization rates among incident hemodialysis patients in a large, nationally representative contemporary cohort. Using US Renal Data System data for 130,892 patients who initiated in-center hemodialysis between October 1, 2003 and September 30, 2006, we determined associations between the frequency of provider visits and mortality, first hospitalization, multiple hospitalizations, and cause-specific hospitalizations. Our primary analysis used Cox proportional hazards models, but we also performed time-varying Cox proportional hazards and instrumental variable analyses. In the primary analysis, we did not detect a significance difference in mortality among patients with four provider visits per month compared with those patients with fewer provider visits (adjusted HR=0.98; 95% CI=0.96-1.01), but the risk for first hospitalization was 4% lower among those patients with more frequent visits (adjusted HR=0.96; 95% CI=0.95-0.97). The time-varying Cox analysis produced similar results. The fully adjusted instrumental variable analysis showed a 0.07% higher risk for death that was not statistically significant (P=0.88) but a significant 2.3% lower risk for first hospitalization (P=0.001) for patients with four provider visits per month. In summary, greater frequency of provider visits to hemodialysis patients associates with a small but significant reduction in hospitalizations, but it does not consistently associate with lower risk for death.
Assuntos
Instituições de Assistência Ambulatorial/estatística & dados numéricos , Falência Renal Crônica/terapia , Medicaid/estatística & dados numéricos , Medicare/estatística & dados numéricos , Pacientes Ambulatoriais/estatística & dados numéricos , Diálise Renal , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Falência Renal Crônica/mortalidade , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento , Estados UnidosRESUMO
BACKGROUND: In 2007, the National Kidney Foundation (NKF) published clinical practice guidelines and recommendations for treating patients with diabetes and kidney diseases. Given recent studies that may enhance our understanding of the benefits and harms of glycemic, lipid, and albuminuria management in patients with diabetes and chronic kidney disease (CKD), the NKF commissioned a systematic review to evaluate data on the management of these patients. STUDY DESIGN: Systematic review and evidence synthesis. SETTING & POPULATION: Patients with type 1 or 2 diabetes with or without CKD. SELECTION CRITERIA FOR STUDIES: English-language publications indexed in the MEDLINE database from January 2003 to October 2010, as well as cited references in these publications and publications identified after consultation with the NKF Diabetes Work Group were screened. Randomized controlled trials providing evidence for the management of hyperglycemia, dyslipidemia, and albuminuria in individuals with diabetes were included. INTERVENTIONS: (1) Intensive glycemic control; (2) lipid management; (3) interventions aimed at prevention of incident albuminuria and/or progression of albuminuria in normotensive patients. OUTCOMES: For all interventions, all-cause mortality was the primary outcome and secondary clinical outcomes included death from cardiovascular causes, incident kidney failure, and nonfatal cardiovascular events. Intermediate outcomes included changes in albuminuria and measures of kidney function. For intensive glycemic control only, severe and mild hypoglycemia were secondary and intermediate outcomes, respectively. RESULTS: 5 studies (n=27,159) assessed the impact of intensive versus conventional glycemic control strategies on clinical outcomes in type 2 diabetes. Intensive glycemic control reduced the development of micro- and macroalbuminuria, but did not reduce the incidence of primary or secondary clinical outcomes and was associated with a 2.5-fold increase in severe hypoglycemia. 11 studies (n=7,539) assessed lipid management. Statins did not reduce all-cause mortality or stroke compared to placebo in adults with diabetes and CKD. Fenofibrate increased regression of microalbuminuria to normoalbuminuria compared to placebo. 3 studies reported inconsistent effects of different angiotensin II receptor blockers on the incidence of microalbuminuria, and one study reported that telmisartan reduced macroalbuminuria in normotensive participants. No study demonstrated a benefit on primary or secondary clinical outcomes. LIMITATIONS: Patients with CKD constituted a subgroup in most studies. Substantial heterogeneity with respect to population, interventions, outcome measures, and duration of follow-up. CONCLUSIONS: Intensive glycemic control and lipid interventions did not improve clinical outcomes in patients with type 2 diabetes. Although interventions typically improved albuminuria, evidence was insufficient to determine whether treatment of albuminuria in normotensive patients provides beneficial effects on clinical outcomes. More intensive clinical management of patients with diabetes and CKD has inherent risks, including severe hypoglycemia, which should be considered when formulating treatment strategies.
Assuntos
Albuminúria/etiologia , Albuminúria/terapia , Complicações do Diabetes/etiologia , Complicações do Diabetes/terapia , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 2/complicações , Dislipidemias/etiologia , Dislipidemias/terapia , Hiperglicemia/etiologia , Hiperglicemia/terapia , Insuficiência Renal Crônica/complicações , Humanos , Guias de Prática Clínica como AssuntoRESUMO
BACKGROUND: Since January 2002, Medicare has provided payment for medical nutrition therapy for patients with chronic kidney disease. Few patients receive dietary counseling before end-stage renal disease onset; whether such counseling is associated with improved outcomes is unknown. STUDY DESIGN: Retrospective cohort analysis. SETTING & PARTICIPANTS: Patients who initiated hemodialysis therapy on June 1, 2005, to May 31, 2007, in the United States for whom predialysis dietitian care was reported on the Centers for Medicare & Medicaid Services Medical Evidence Report. PREDICTOR: Dietitian care before end-stage renal disease onset. OUTCOME: Time to death. MEASUREMENTS: Propensity score for dietitian care calculated using logistic regression; Cox regression analysis used to compare time to death by predialysis dietitian care overall and stratified by tertiles of propensity score, adjusting for baseline characteristics. RESULTS: Most patients (88%) received no dietitian care; 9% received dietitian care for 12 months or less, and 3% received dietitian care for more than 12 months before dialysis therapy initiation (total N = 156,440). Predialysis dietitian care was associated independently with higher albumin and lower total cholesterol levels at dialysis therapy initiation. There was evidence of an independent association between predialysis dietitian care for longer than 12 months and decreased mortality during the first year on dialysis therapy for the second tertile of propensity score. Adjusted mortality HRs were 1.16 (95% CI, 0.44-3.09; P = 0.8), 0.81 (95% CI, 0.71-0.93; P = 0.002), and 0.93 (95% CI, 0.86-1.01; P = 0.1) in the first, second, and third tertiles of propensity score, respectively. LIMITATIONS: Information for dietitian care was missing for 18.6% of Medical Evidence Reports and has low sensitivity; including only incident dialysis patients precluded evaluation of an association between dietitian care and chronic kidney disease progression; the observational design allowed the possibility of residual confounding. CONCLUSIONS: Our study suggests an independent association between predialysis dietitian care for more than 12 months and lower mortality during the first year on dialysis therapy.
Assuntos
Dietética , Nefropatias/dietoterapia , Diálise Renal , Adulto , Idoso , Idoso de 80 Anos ou mais , Albuminúria/epidemiologia , Colesterol/sangue , Doença Crônica , Comorbidade , Aconselhamento , Progressão da Doença , Feminino , Seguimentos , Hemoglobinas Glicadas/análise , Humanos , Nefropatias/sangue , Nefropatias/terapia , Falência Renal Crônica/sangue , Falência Renal Crônica/mortalidade , Falência Renal Crônica/prevenção & controle , Falência Renal Crônica/terapia , Masculino , Medicaid/estatística & dados numéricos , Medicare/estatística & dados numéricos , Pessoa de Meia-Idade , Desnutrição Proteico-Calórica/epidemiologia , Desnutrição Proteico-Calórica/prevenção & controle , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Estados Unidos/epidemiologia , Adulto JovemRESUMO
PURPOSE: To investigate cerebral blood flow (CBF) characteristics before and after hemodialysis initiation and their longitudinal associations with global cognitive function in older adults. METHODS: A cohort of 17 older end-stage renal disease patients anticipating standard thrice-weekly hemodialysis and a group of 11 age- and sex-matched healthy control volunteers were recruited for brain perfusion imaging studies using arterial spin labeling. Hemodialysis patients participated in a prospective longitudinal study using brain magnetic resonance imaging and global cognitive assessment using the Modified Mini-Mental State Examination (3MS) at two time points: baseline, 2.9 ± 0.9 months before, and follow-up, 6.4 ± 2.4 months after hemodialysis initiation. Healthy controls were imaged once using the same protocol. CBF analyses were performed globally in grey and white matter and regionally in the hippocampus and orbitofrontal cortex. Covariate-adjusted linear mixed-effects models were used for statistical analyses (significance: p < 0.05; marginal significance: p < 0.1). RESULTS: At baseline, global and regional CBF was significantly higher in hemodialysis patients than in healthy controls. However, after approximately 6 months of hemodialysis, CBF declined substantially in hemodialysis patients, and became comparable to those in healthy controls. Specifically, in the hemodialysis patients, CBF declined non-significantly globally for grey and white matter and significantly regionally in the hippocampus and orbitofrontal cortex. Marginally significant associations were observed between 3MS scores and regional CBF measurements in the hippocampus and orbitofrontal cortex at baseline and follow-up, and between longitudinal changes. CONCLUSION: The significant decline in CBF after hemodialysis initiation and the observed association between longitudinal changes in regional CBF and 3MS scores suggest that decreased brain perfusion may contribute to the observed cognitive decline.
Assuntos
Circulação Cerebrovascular , Diálise Renal , Idoso , Encéfalo , Cognição , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Projetos Piloto , Estudos Prospectivos , Marcadores de SpinRESUMO
BACKGROUNDS: There are no national level data on types of dialysis in use for acute kidney injury (AKI). We aimed to assess trends in dialysis modality for AKI and mortality associated with each modality from 1998 to 2005. METHODS: Using data from the 5% Medicare cohort, we identified individuals with AKI requiring dialysis. Individuals with preexisting end-stage renal disease were excluded. Intermittent hemodialysis (IHD), daily intermittent hemodialysis, and continuous renal replacement therapy (CRRT) were defined using Current Procedure Terminology codes. Mortality was defined as death during 30 days after the first dialysis session. RESULTS: Between 1998 and 2005, there were a total of 18,249 patients identified with AKI requiring renal replacement therapy. CRRT was increasingly used for AKI, with 9.9% of patients in 1998 to 18.3% by 2005. Proportion of daily dialysis decreased during this period, while use of IHD remained stable at approximately 68%. Overall 30-day mortality declined from 44.4% in 1998 to 40.2% in 2005. Crude mortality for CRRT was highest in all years (51.0-61.8%), followed by daily (38.2-49.9%) and IHD groups (35.8-43.4%). Multinomial logistic regression analysis showed that white race, presence of sepsis, atherosclerotic heart diseases, peripheral vascular diseases, dysrhythmia, gastrointestinal and liver diseases, and any year after 2000 were independently associated with higher odds of using CRRT after adjusting for other variables. CONCLUSION: The proportion of patients using CRRT has increased over time. Mortality associated with IHD has decreased from 1998 to 2005. Mortality associated with different dialysis modalities is likely the result of severity of illness.
Assuntos
Injúria Renal Aguda/terapia , Terapia de Substituição Renal/tendências , Injúria Renal Aguda/epidemiologia , Idoso , Comorbidade , Feminino , Humanos , Masculino , Terapia de Substituição Renal/métodos , Estados Unidos/epidemiologiaRESUMO
Background: Our primary goal is to describe the prevalence, severity, and risk of cognitive impairment (CI) by estimated glomerular filtration rate (eGFR, in mL/min/1.73 m2) in a cohort enriched for advanced chronic kidney disease (CKD; eGFR < 45), adjusting for albuminuria, as measured by urine albumin-to-creatinine ratio (UACR, in mg/g). As both eGFR and albuminuria are associated with CI risk in CKD, we also seek to determine the extent that eGFR remains a useful biomarker for risk of CI in those with CKD and concomitant albuminuria. Methods: Chi-square tests measured the prevalence of severe CI and mild cognitive impairment (MCI) by eGFR level. Logistic regression models and generalized linear models measured risk of CI by eGFR, adjusted for UACR. Results: Participants were 574 adults with a mean age of 69; 433 with CKD (eGFR < 60, nondialysis) and 141 controls (eGFR ≥ 60). Forty-eight percent of participants with CKD had severe CI or MCI. The prevalence of severe CI was highest (25%) in those with eGFR < 30. eGFR < 30 was only associated with severe CI in those without albuminuria (UACR < 30; OR = 3.3; p = .02) and was not associated with MCI in similar models. Conclusions: One quarter of those with eGFR < 30 had severe CI. eGFR < 30 was associated with over threefold increased odds of severe CI in those with UACR < 30, but not with UACR > 30, suggesting that eGFR < 30 is a valid biomarker for increased risk of severe CI in those without concomitant albuminuria.
Assuntos
Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/etiologia , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/epidemiologia , Idoso , Albuminúria/complicações , Albuminúria/epidemiologia , Feminino , Taxa de Filtração Glomerular , Humanos , Testes de Função Renal , Masculino , Minnesota/epidemiologia , Prevalência , Risco , Índice de Gravidade de DoençaRESUMO
Despite advances in the medical management of secondary hyperparathyroidism, parathyroidectomy remains necessary in some end-stage renal disease patients. Observational studies may help with the design of intervention trials. We linked the retrospective Waves 1, 3, and 4 Dialysis Morbidity and Mortality Study datasets to Medicare claims data to identify incident parathyroidectomy in 10,588 Medicare patients receiving hemodialysis in the United States on December 31, 1993. The mean age was 60.0 years, and the mean follow-up 3.6 years. De novo parathyroidectomy incidence was 14.2/1000 patient-years. Considered as quintiles (Q), higher levels of standard bone metabolism variables were associated (p<0.0001) with parathyroidectomy stepwise, such that adjusted hazards ratios (AHR) for Q5 (vs. Q1) were, for calcium (>10.3 mg/dL), 5.09 (3.64-7.10); for phosphorus (>7.5 mg/dL), 2.92 (2.06-4.15); for calcium-phosphorus product (>71 mg2/dL2), 3.32 (2.27-4.85); and for parathyroid hormone (PTH; >480 pg/mL), 13.81 (7.47-25.55). Other antecedent associations included younger age, lower hemoglobin, and longer dialysis vintage, while transplantation, as a time-dependent covariate, was associated with lower hazards ratios. Using interval Poisson analysis, parathyroidectomy was associated with higher mortality risk ratios in the first year, and progressively lower risk ratios subsequently. Demographic variables may modify the risk of parathyroidectomy. Younger patients on long-term hemodialysis may be at a special risk. Parathyroidectomy risk increases stepwise with alterations in bone metabolism variables, suggesting that a single-threshold management approach may not be ideal.
Assuntos
Hiperparatireoidismo Secundário/epidemiologia , Falência Renal Crônica/complicações , Paratireoidectomia/estatística & dados numéricos , Diálise Renal , Adulto , Idoso , Osso e Ossos/metabolismo , Coleta de Dados , Epidemiologia , Feminino , Humanos , Hiperparatireoidismo Secundário/mortalidade , Incidência , Masculino , Pessoa de Meia-Idade , Razão de Chances , Paratireoidectomia/mortalidade , Fatores de RiscoRESUMO
BACKGROUND: Chronic kidney disease (CKD) studies have reported variable prevalence of brain pathologies, in part due to low inclusion of participants with moderate to severe CKD. OBJECTIVE: To measure the association between kidney function biomarkers and brain MRI findings in CKD. METHODS: In the BRINK (BRain IN Kidney Disease) study, MRI was used to measure gray matter volumes, cerebrovascular pathologies (white matter hyperintensity (WMH), infarctions, microhemorrhages), and microstructural changes using diffusion tensor imaging (DTI). We performed regression analyses with estimated glomerular filtration rate (eGFR) and urine albumin to creatinine ratio (UACR) as primary predictors, and joint models that included both predictors, adjusted for vascular risk factors. RESULTS: We obtained 240 baseline MRI scans (150 CKD with eGFR <45 in ml/min/1.73 m2; 16 mild CKD: eGFR 45-59; 74 controls: eGFR≥60). Lower eGFR was associated with greater WMH burden, increased odds of cortical infarctions, and worsening diffusion changes throughout the brain. In eGFR models adjusted for UACR, only cortical infarction associations persisted. However, after adjusting for eGFR, higher UACR provided additional information related to temporal lobe atrophy, increased WMH, and whole brain microstructural changes as measured by increased DTI mean diffusivity. CONCLUSIONS: Biomarkers of kidney disease (eGFR and UACR) were associated with MRI brain changes, even after accounting for vascular risk factors. UACR adds unique additional information to eGFR regarding brain structural and diffusion biomarkers. There was a greater impact of kidney function biomarkers on cerebrovascular pathologies and microstructural brain changes, suggesting that cerebrovascular etiology may be the primary driver of cognitive impairment in CKD.
Assuntos
Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Insuficiência Renal Crônica/patologia , Substância Branca/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Encéfalo/patologia , Infarto Encefálico/diagnóstico por imagem , Infarto Encefálico/epidemiologia , Estudos de Coortes , Imagem de Tensor de Difusão/métodos , Feminino , Taxa de Filtração Glomerular/fisiologia , Hemorragia/epidemiologia , Humanos , Processamento de Imagem Assistida por Computador , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Insuficiência Renal Crônica/diagnóstico por imagem , Insuficiência Renal Crônica/epidemiologia , Substância Branca/patologiaRESUMO
The effect of clinic-based intensive hypertension treatment on ambulatory blood pressure (BP) is unknown. The goal of the SPRINT (Systolic Blood Pressure Intervention Trial) ambulatory BP ancillary study was to evaluate the effect of intensive versus standard clinic-based BP targets on ambulatory BP. Ambulatory BP was obtained within 3 weeks of the 27-month study visit in 897 SPRINT participants. Intensive treatment resulted in lower clinic systolic BP (mean difference between groups=16.0 mm Hg; 95% confidence interval, 14.1-17.8 mm Hg), nighttime systolic BP (mean difference=9.6 mm Hg; 95% confidence interval, 7.7-11.5 mm Hg), daytime systolic BP (mean difference=12.3 mm Hg; 95% confidence interval, 10.6-13.9 mm Hg), and 24-hour systolic BP (mean difference=11.2 mm Hg; 95% confidence interval, 9.7-12.8 mm Hg). The night/day systolic BP ratio was similar between the intensive (0.92±0.09) and standard-treatment groups (0.91±0.09). There was considerable lack of agreement within participants between clinic systolic BP and daytime ambulatory systolic BP with wide limits of agreement on Bland-Altman plots. In conclusion, targeting a systolic BP of <120 mm Hg, when compared with <140 mm Hg, resulted in lower nighttime, daytime, and 24-hour systolic BP, but did not change the night/day systolic BP ratio. Ambulatory BP monitoring may be required to assess the effect of targeted hypertension therapy on out of office BP. Further studies are needed to assess whether targeting hypertension therapy based on ambulatory BP improves clinical outcomes. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01835249.
Assuntos
Anti-Hipertensivos/uso terapêutico , Monitorização Ambulatorial da Pressão Arterial/métodos , Pressão Sanguínea/fisiologia , Hipertensão/fisiopatologia , Idoso , Feminino , Seguimentos , Humanos , Hipertensão/diagnóstico , Masculino , Sístole , Fatores de TempoRESUMO
BACKGROUND: In an effort to improve outcomes associated with living kidney donation, the Kidney Diseases Improving Global Outcomes (KDIGO) assembled a Work Group to develop comprehensive guidelines addressing the evaluation and care of living kidney donors. We conducted this systematic review to inform guideline development. METHODS: We searched Ovid Medline, Ovid Embase, and the Cochrane Library to identify systematic reviews, randomized controlled trials, and observational studies published through September of 2014 and consulted the KDIGO Expert Work Group. We extracted data from systematic reviews and observational studies with sample size over 100 and mean follow-up time of at least 5 years. Studies had to have an adequate comparison group that excludes subjects with contraindications to kidney donation. RESULTS: For the long-term donor outcomes, we extracted 5 systematic reviews and 40 observational studies. Moderate grade evidence reveals an association between living kidney donation and greater risk of end-stage renal disease. This association is true for donors of all races with African American donors sustaining the greatest increase in absolute risk. We found very low grade evidence that kidney donation is associated with lower kidney function, proteinuria, hypertension, and psychosocial outcomes. Consistent evidence from 3 studies reveals that donors are at higher risk for preeclampsia and gestational hypertension with postdonation pregnancies and compared with healthy matched nondonors. CONCLUSIONS: Living kidney donation appears to be associated with a small absolute increase in risk of end-stage renal disease, hypertension, and pregnancy complications, such as preeclampsia and gestational hypertension.
RESUMO
BACKGROUND: Serum biomarkers predicting physical performance in late life are uncertain. We tested the hypotheses that lower serum cystatin C (cysC) in older women is associated with good mobility 10 years later. METHODS: We conducted a longitudinal analysis of a prospective cohort of 1,384 women attending Year 10 and Year 20 examinations of the Study of Osteoporotic Fractures. Serum cysC was measured using Year 10 frozen serum specimens. Year 20 mobility was ascertained by the Short Physical Performance Battery; scores of 10-12 indicated good mobility. RESULTS: At Year 20, mean age was 87.5 years and 364 women (26.3%) had good mobility. After adjustment for age, race, education, health status, diabetes, cardiovascular disease, and body mass index, lower cysC at Year 10 was associated with a higher likelihood of good mobility at Year 20. Compared with quartile (Q) 4 of cysC (referent group), odds ratios (95% confidence interval) were 1.52 (1.02-2.25) for Q3, 1.93 (1.32-2.84) for Q2 and 1.80 (1.21-2.67) for Q1 (p trend across Qs .003). The association was only modestly attenuated after further adjustment for mobility as assessed by a modified Short Physical Performance Battery at Year 10 (p trend .02) or consideration of potential biologic mediators including Year 10 levels of serum 25-hydroxyvitamin D, interleukin 6, and cytokine soluble receptors (p trend .04). CONCLUSIONS: Lower cysC in older women is independently associated with good mobility 10 years later and may be a biomarker for successful aging as manifested by preservation of lower extremity performance in late life.