RESUMEN
BACKGROUND: End-stage renal disease is accompanied by functional and structural vascular abnormalities. The objective of this study was to characterize vascular function in a large cohort of patients with end-stage renal disease, using noninvasive physiological measurements, and to correlate function with demographic and clinical factors. METHODS AND RESULTS: We analyzed cross-sectional baseline data from the Hemodialysis Fistula Maturation Study, a multicenter prospective observational cohort study of 602 patients with end-stage renal disease from 7 centers. Brachial artery flow- and nitroglycerin-mediated dilation, carotid-femoral and -radial pulse wave velocity, and venous occlusion plethysmography were performed prior to arteriovenous fistula creation. Relationships of these vascular function measures with demographic, clinical, and laboratory factors were evaluated using linear mixed-effects models. Arterial function, as assessed by flow- and nitroglycerin-mediated dilation and carotid-femoral pulse wave velocity, worsened with increasing age and diabetes mellitus. Venous capacitance decreased with diabetes mellitus but not with age. Flow-mediated dilation was higher among patients undergoing maintenance dialysis than for those at predialysis, and a U-shaped relationship between serum phosphorus concentration and flow-mediated dilation was evident. Partial correlations among different measures of vascular function, adjusting for demographic factors, diabetes mellitus, and clinical center, were modest or essentially nonexistent. CONCLUSIONS: Multiple demographic and clinical factors were associated with the functions of vessels of different sizes and types in this large cohort of patients with end-stage renal disease. Low correlations between the different measures, controlling for demographic factors, diabetes mellitus, and center, indicated that these different types of vascular function otherwise vary heterogeneously across patients.
Asunto(s)
Anastomosis Quirúrgica , Arteria Braquial/fisiopatología , Fallo Renal Crónico/terapia , Análisis de la Onda del Pulso , Diálisis Renal , Procedimientos Quirúrgicos Vasculares , Vasodilatación/fisiología , Adulto , Anciano , Estudios de Cohortes , Estudios Transversales , Femenino , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Nitroglicerina , Pletismografía , Estudios Prospectivos , VasodilatadoresRESUMEN
BACKGROUND AND OBJECTIVES: The prevalence of ESRD among Hispanics/Latinos is 2-fold higher than in non-Hispanic whites. However, little is known about the prevalence of earlier stages of CKD among Hispanics/Latinos. This study estimated the prevalence of CKD in US Hispanics/Latinos. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: This was a cross-sectional study of 15,161 US Hispanic/Latino adults of Cuban, Dominican, Mexican, Puerto Rican, Central American, and South American backgrounds enrolled in the multicenter, prospective, population-based Hispanic Community Health Study/Study of Latinos (HCHS/SOL). In addition, the prevalence of CKD in Hispanics/Latinos was compared with other racial/ethnic groups in the 2007-2010 National Health and Nutrition Examination Survey (NHANES). Prevalent CKD was defined as an eGFR <60 ml/min per 1.73 m(2) (estimated with the 2012 Chronic Kidney Disease Epidemiology Collaboration eGFR creatinine-cystatin C equation) or albuminuria based on sex-specific cut points determined at a single point in time. RESULTS: The overall prevalence of CKD among Hispanics/Latinos was 13.7%. Among women, the prevalence of CKD was 13.0%, and it was lowest in persons with South American background (7.4%) and highest (16.6%) in persons with Puerto Rican background. In men, the prevalence of CKD was 15.3%, and it was lowest (11.2%) in persons with South American background and highest in those who identified their Hispanic background as "other" (16.0%). The overall prevalence of CKD was similar in HCHS/SOL compared with non-Hispanic whites in NHANES. However, prevalence was higher in HCHS/SOL men and lower in HCHS/SOL women versus NHANES non-Hispanic whites. Low income, diabetes mellitus, hypertension, and cardiovascular disease were each significantly associated with higher risk of CKD. CONCLUSIONS: Among US Hispanic/Latino adults, there was significant variation in CKD prevalence among Hispanic/Latino background groups, and CKD was associated with established cardiovascular risk factors.
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Hispánicos o Latinos/estadística & datos numéricos , Insuficiencia Renal Crónica/etnología , Adolescente , Adulto , Anciano , Enfermedades Cardiovasculares/etnología , América Central/etnología , Estudios Transversales , Cuba/etnología , Diabetes Mellitus/etnología , República Dominicana/etnología , Femenino , Tasa de Filtración Glomerular , Humanos , Masculino , México/etnología , Persona de Mediana Edad , Encuestas Nutricionales , Pobreza , Prevalencia , Estudios Prospectivos , Puerto Rico/etnología , Insuficiencia Renal Crónica/epidemiología , Insuficiencia Renal Crónica/fisiopatología , Factores de Riesgo , Factores Sexuales , América del Sur/etnología , Estados Unidos/epidemiología , Población Blanca/estadística & datos numéricos , Adulto JovenRESUMEN
OBJECTIVES: This report assesses participant perception of treatment assignment in a randomized, double-blind, placebo-controlled trial of saw palmetto for the treatment of benign prostatic hyperplasia (BCM). DESIGN: Participants randomized to receive saw palmetto were instructed to take one 320 mg gelcap daily for the first 24 weeks, two 320 mg gelcaps daily for the second 24 weeks, and three 320 mg gelcaps daily for the third 24 weeks. Study participants assigned to placebo were instructed to take the same number of matching placebo gelcaps in each time period. At 24, 48, and 72 weeks postrandomization, the American Urological Association Symptom Index (AUA-SI) was administered and participants were asked to guess their treatment assignment. SETTINGS: The study was conducted at 11 clinical centers in North America. PARTICIPANTS: Study participants were men, 45 years and older, with moderate to low severe BPH symptoms, randomized to saw palmetto (N=151) or placebo (N=155). OUTCOME MEASURES: Treatment arms were compared with respect to the distribution of participant guesses of treatment assignment. RESULTS: For participants assigned to saw palmetto, 22.5%, 24.7%, and 29.8% correctly thought they were taking saw palmetto, and 37.3%, 40.0%, and 44.4% incorrectly thought they were on placebo at 24, 48, and 72 weeks, respectively. For placebo participants, 21.8%, 27.4%, and 25.2% incorrectly thought they were on saw palmetto, and 41.6%, 39.9%, and 42.6% correctly thought they were on placebo at 24, 48, and 72 weeks, respectively. The treatment arms did not vary with respect to the distributions of participants who guessed they were on saw palmetto (p=0.823) or placebo (p=0.893). Participants who experienced an improvement in AUA-SI were 2.16 times more likely to think they were on saw palmetto. CONCLUSIONS: Blinding of treatment assignment was successful in this study. Improvement in BPH-related symptoms was associated with the perception that participants were taking saw palmetto.
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Extractos Vegetales/administración & dosificación , Ensayos Clínicos Controlados Aleatorios como Asunto/psicología , Sujetos de Investigación/psicología , Anciano , Método Doble Ciego , Humanos , Masculino , Persona de Mediana Edad , Placebos , Hiperplasia Prostática/tratamiento farmacológico , SerenoaRESUMEN
BACKGROUND: Hyperuricemia is prevalent in patients with chronic kidney disease (CKD); however, data are limited about the relationship of uric acid levels with long-term outcomes in this patient population. STUDY DESIGN: Cohort study. SETTING & PARTICIPANTS: The Modification of Diet in Renal Disease (MDRD) Study was a randomized controlled trial (N = 840) conducted from 1989 to 1993 to examine the effects of strict blood pressure control and dietary protein restriction on progression of stages 3 to 4 CKD. This analysis included 838 patients. PREDICTOR: Uric acid level. OUTCOMES & MEASUREMENTS: The study evaluated the association of baseline uric acid levels with all-cause mortality, cardiovascular disease (CVD) mortality, and kidney failure. RESULTS: Mean age was 52 +/- 12 (SD) years, glomerular filtration rate was 33 +/- 12 mL/min/1.73 m(2), and uric acid level was 7.63 +/- 1.66 mg/dL. During a median follow-up of 10 years, 208 (25%) participants died of any cause, 127 (15%) died of CVD, and 553 (66%) reached kidney failure. In multivariate models, the highest tertile of uric acid was associated with increased risk of all-cause mortality (hazard ratio [HR], 1.57; 95% confidence interval [CI], 1.07 to 2.32), a trend toward CVD mortality (HR, 1.47; 95% CI, 0.90 to 2.39), and no association with kidney failure (HR, 1.20; 95% CI, 0.95 to 1.51) compared with the lowest tertile. In continuous analyses, a 1-mg/dL greater uric acid level was associated with 17% increased risk of all-cause mortality (HR, 1.17; 95% CI, 1.05 to 1.30) and 16% increased risk of CVD mortality (HR, 1.16; 95% CI, 1.01 to 1.33), but was not associated with kidney failure (HR, 1.02; 95% CI, 0.97 to 1.07). LIMITATIONS: Primary analyses were based on a single measurement of uric acid. Results are generalizable primarily to relatively young white patients with predominantly nondiabetic CKD. CONCLUSIONS: In patients with stages 3 to 4 CKD, hyperuricemia appears to be an independent risk factor for all-cause and CVD mortality, but not kidney failure.
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Hiperuricemia/epidemiología , Fallo Renal Crónico/sangre , Ácido Úrico/sangre , Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/complicaciones , Enfermedades Cardiovasculares/mortalidad , Causas de Muerte/tendencias , Intervalos de Confianza , Femenino , Estudios de Seguimiento , Tasa de Filtración Glomerular/fisiología , Humanos , Hiperuricemia/sangre , Hiperuricemia/etiología , Riñón/fisiopatología , Fallo Renal Crónico/complicaciones , Fallo Renal Crónico/mortalidad , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia/tendencias , Factores de Tiempo , Estados Unidos/epidemiologíaRESUMEN
BACKGROUND: Hyperhomocysteinemia may be a modifiable risk factor for the prevention of arteriosclerotic outcomes in patients with chronic kidney disease (CKD). Few clinical trials of homocysteine lowering have been conducted in persons with CKD before reaching end-stage renal disease. Kidney transplant recipients are considered individuals with CKD. OBJECTIVES: To describe the baseline characteristics of renal transplant recipients enrolled in a clinical trial of homocysteine lowering with a standard multivitamin containing high doses of folic acid and vitamins B(6) and B(12) aimed at reducing arteriosclerotic outcomes. Factors considered were level of kidney function, total homocysteine concentration, and prevalence of diabetes and previous cardiovascular disease (CVD). STUDY DESIGN: Cross-sectional survey within a randomized controlled trial cohort. SETTING & PARTICIPANTS: Participants were recruited from kidney transplant clinics in the United States, Canada, and Brazil. Eligible participants had increased levels of homocysteine (> or =12.0 micromol/L in men and > or =11.0 micromol/L in women) and kidney function measured by means of Cockroft-Gault estimated creatinine clearance of 30 mL/min or greater. RESULTS: Of 4,110 randomly assigned participants, 38.9% had diabetes and 19.5% had previous CVD. Mean total homocysteine concentration was 17.1 +/- 6.3 (SD) micromol/L, whereas mean creatinine clearance was 66.4 +/- 23.2 mL/min. Approximately 90% of the trial cohort had an estimated glomerular filtration rate consistent with stages 2 to 3 CKD (i.e., 30 to 89 mL/min). LIMITATIONS: Analysis is based on cross-sectional data from a randomized controlled trial, self-report of comorbid illnesses, and level of kidney function was estimated. CONCLUSIONS: A large population of stable renal transplant recipients who are at high risk of the development of CVD (both de novo and recurrent) has been recruited into the Folic Acid for Vascular Outcome Reduction in Transplantation Trial and are likely to experience a sufficient number of events to address the primary hypothesis of the trial.