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BACKGROUND: The association between cardiac complications, such as heart failure (HF), and chronic kidney disease (CKD) is well known. In this study, we examined the effectiveness and safety of treatment with neprilysin inhibition in patients with advanced chronic kidney disease (stage 3b-4). METHODS: This single-centre, longitudinal, retrospective study of 31 months duration involved consecutive patients with CKD and HF with a reduced ejection fraction (HFrEF) who started treatment with sacubitril/valsartan. Glomerular filtration rate (GFR), cardiovascular risk factors, proteinuria, potassium, echocardiographic parameters and admissions for heart failure were analysed. RESULTS: The study comprised 25 patients with a median age of 73.2 ± 5.9 years. The most frequent aetiology of heart failure was ischemic heart disease. The median GFR was 29.4 ± 8.3 ml/min/1.73 m2 and the left ventricular ejection fraction (LVEF) 36.4 ± 8.9%. The GFR improved after initiating the treatment (F = 3.396, p = 0.019), as did the LVEF at one year of follow-up (p = 0.018). The number of visits to the emergency department for heart failure was also reduced. No patients needed to start renal replacement therapy. CONCLUSIONS: This study shows that sacubitril/valsartan may play a beneficial role in patients who have advanced CKD and HFrEF, with a satisfactory safety profile.
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Aminobutiratos , Compuestos de Bifenilo , Insuficiencia Cardíaca , Insuficiencia Renal Crónica , Valsartán , Anciano , Aminobutiratos/uso terapéutico , Compuestos de Bifenilo/uso terapéutico , Combinación de Medicamentos , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/tratamiento farmacológico , Humanos , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/tratamiento farmacológico , Estudios Retrospectivos , Volumen Sistólico , Valsartán/uso terapéutico , Función Ventricular IzquierdaRESUMEN
BACKGROUND: Subclinical inflammation, including borderline lesions (BL), is very common (30-40%) after kidney transplantation (KT), even in low immunological risk patients, and can lead to interstitial fibrosis/tubular atrophy (IFTA) and worsening of renal function with graft loss. Few controlled studies have analyzed the therapeutic benefit of treating these BL on renal function and graft histology. Furthermore, these studies have only used bolus steroids, which may be insufficient to slow the progression of these lesions. Klotho, a transmembrane protein produced mainly in the kidney with antifibrotic properties, plays a crucial role in the senescence-inflammation binomial of kidney tissue. Systemic and local inflammation decrease renal tissue expression and soluble levels of α-klotho. It is therefore important to determine whether treatment of BL prevents a decrease in α-klotho levels, progression of IFTA, and loss of kidney function. METHODS: The TRAINING study will randomize 80 patients with low immunological risk who will receive their first KT. The aim of the study is to determine whether the treatment of early BL (3rd month post-KT) with polyclonal rabbit antithymocyte globulin (Grafalon®) (6 mg/kg/day) prevents or decreases the progression of IFTA and the worsening of graft function compared to conventional therapy after two years post-KT, as well as to analyze whether treatment of BL with Grafalon® can modify the expression and levels of klotho, as well as the pro-inflammatory cytokines that regulate its expression. DISCUSSION: This phase IV investigator-driven, randomized, placebo-controlled clinical trial will examine the efficacy and safety of Grafalon® treatment in low-immunological-risk KT patients with early BL. TRIAL REGISTRATION: clinicaltrials.gov : NCT04936282. Registered June 23, 2021, https://clinicaltrials.gov/ct2/show/NCT04936282?term=NCT04936282&draw=2&rank=1 . Protocol Version 2 of 21 January 2022. SPONSOR: Canary Isles Institute for Health Research Foundation, Canary Isles (FIISC). mgomez@fciisc.org .
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Enfermedades Renales , Trasplante de Riñón , Humanos , Trasplante de Riñón/efectos adversos , Trasplante de Riñón/métodos , Riñón/patología , Enfermedades Renales/patología , Proyectos de Investigación , Inflamación/etiología , Rechazo de Injerto/prevención & control , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Multicéntricos como Asunto , Ensayos Clínicos Fase IV como AsuntoRESUMEN
BACKGROUND: The risk-benefit of antithrombotic treatment (ATT) has not been established in patients on dialysis. Our objective was to determine the influence of ATT on the risk of hemorrhage in patients on hemodialysis. METHODS: We included patients who began dialysis between 2003 and 2007. We determined the rates of fatal bleeding or bleeding leading to hospitalization or transfusion. RESULTS: Two hundred twenty-one patients were included. Over the follow-up period (45.5 ± 34 months), there were 76 hemorrhages in 52 patients. There were 10 fatal bleedings. The annual incidence of patients presenting with hemorrhagia was 6.2%. Bleeding occurred in 5.2% of those being treated with aspirin, 7% with acenocumarol, 12.3% with clopidogrel, 15.2% with aspirin + clopidogrel, 45.9% with anticoagulants + antiplatelets, 49.6% with low-molecular-weight heparin, and 3.9% without ATT. On multivariate analysis, masculine gender [hazard ratio (HR): 2.421; 95% confidence interval (CI), 1.261-4.650; P = 0.003], treatment with dicumarins (HR: 2.406; 95% CI, 1.013-5.718; P = 0.047), treatment with clopidogrel (HR: 2.697; 95% CI, 1.440-5.051; P = 0.002), and treatment with low-molecular-weight heparin (HR: 21.463; 95% CI, 9.067-50.806; P = 0.001) were independent predictors of bleeding. CONCLUSIONS: ATT increases the risk of bleeding in patients on hemodialysis. The incidence of hemorrhage varies with the type of antithrombotics used.
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Fibrinolíticos/efectos adversos , Hemorragia/inducido químicamente , Fallo Renal Crónico/terapia , Diálisis Renal/efectos adversos , Diálisis Renal/tendencias , Adulto , Anciano , Anciano de 80 o más Años , Anticoagulantes/efectos adversos , Femenino , Estudios de Seguimiento , Hemorragia/diagnóstico , Humanos , Fallo Renal Crónico/diagnóstico , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Resultado del Tratamiento , Adulto JovenRESUMEN
Background: Immunoglobulin A nephropathy (IgAN) is the most frequent recurrent disease in kidney transplant recipients and its recurrence contributes to reducing graft survival. Several variables at the time of recurrence have been associated with a higher risk of graft loss. The presence of clinical or subclinical inflammation has been associated with a higher risk of kidney graft loss, but it is not precisely known how it influences the outcome of patients with recurrent IgAN. Methods: We performed a multicentre retrospective study including kidney transplant recipients with biopsy-proven recurrence of IgAN in which Banff and Oxford classification scores were available. 'Tubulo-interstitial inflammation' (TII) was defined when 't' or 'i' were ≥2. The main endpoint was progression to chronic kidney disease (CKD) stage 5 or to death censored-graft loss (CKD5/DCGL). Results: A total of 119 kidney transplant recipients with IgAN recurrence were included and 23 of them showed TII. Median follow-up was 102.9 months and 39 (32.8%) patients reached CKD5/DCGL. TII related to a higher risk of CKD5/DCGL (3 years 18.0% vs 45.3%, log-rank 7.588, P = .006). After multivariate analysis, TII remained related to the risk of CKD5/DCGL (HR 2.344, 95% CI 1.119-4.910, P = .024) independently of other histologic and clinical variables. Conclusions: In kidney transplant recipients with IgAN recurrence, TII contributes to increasing the risk of CKD5/DCGL independently of previously well-known variables. We suggest adding TII along with the Oxford classification to the clinical variables to identify recurrent IgAN patients at increased risk of graft loss who might benefit from intensified immunosuppression or specific IgAN therapies.
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BACKGROUND: Frailty is a persistent chronic inflammatory syndrome present in many patients with chronic kidney disease. After kidney transplant (KT), it has been associated with complications such as delayed graft function, hospital readmission, or poorer KT survival. PURPOSE: To assess the impact of frailty on the results of KT. METHODS: Longitudinal prospective study of 65 patients included on the waiting list (WL) between October 2019 and October 2021. We used the FRAIL scale and recorded clinical characteristics, including demographic, dependency scales, and analytical parameters at the moment of the inclusion on the WL and at months 3 and 12 after KT. RESULTS: The mean age was 58 years old, and 70% of KT were men. The comorbidity burden was 26% diabetes, 83% hypertension, and 12% ischemic heart disease. Forty patients (61.5%) presented ≥1 point on the FRAIL scale, and 25 (38.4%) were robust. Frail patients (FRAIL score≥3) had a higher Charlson comorbidity index at the time of KT, a lower Barthel index, and a lower quality of life measured by KDQOL-36. No significant differences were observed in other variables, such as days of admission, surgical complications, or delayed graft function. There were 3 graft losses censored for death and 4 deaths, all in frail or prefrail patients. These patients had lower graft survival (P = .164) and patient survival (P = .096). At 12 months post KT, frailty improved in 67% of patients evaluated. CONCLUSION: Frailty is a common condition among patients on the WL, leading to poorer quality of life, greater dependency, and a higher risk of graft loss and mortality. Frailty conditions can be reversed in many patients after KT.
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Fragilidad , Trasplante de Riñón , Masculino , Humanos , Persona de Mediana Edad , Femenino , Fragilidad/complicaciones , Fragilidad/diagnóstico , Estudios Prospectivos , Calidad de Vida , Funcionamiento Retardado del Injerto/complicaciones , Trasplante de Riñón/efectos adversos , Factores de Riesgo , Receptores de TrasplantesRESUMEN
We investigated the evolution of serum klotho (s-Kl) and FGF-23 during the first two years post-kidney transplantation (KT), considering the cold ischemia time (CIT), glomerular filtration rate (GFR) and graft subclinical inflammation (SCI). We undertook a prospective, cohort, multicenter study of consecutive patients between April 2018 and January 2021 (with follow-up at 24 months). Subgroups were analyzed according to the median CIT (<14 vs. ≥14 h), the median GFR (≤40 vs. >40 mL/min/1.73 m2) and the presence of SCI at month 3. A total of 147 patients were included. s-Kl and fibroblast growth factor-23 (FGF-23) levels were measured at baseline and at months 3, 12 and 24. Graft biopsies (n = 96) were performed at month 3. All patients had low s-Kl levels at month 3. Patients with CIT < 14 h exhibited a significant increase in s-Kl at month 24. In patients with CIT ≥ 14 h, s-Kl at month 3 fell and lower s-Kl levels were seen at month 24. Patients with a GFR > 40 had a lesser decrease in s-Kl at month 3. FGF-23 fell significantly at months 3 and 12 in both GFR groups, a reduction maintained during follow-up. There were significant inter-group differences in s-Kl from months 3 to 24. CIT, GFR at 3 months and SCI were significantly associated with s-KI at month 3. A reduction in s-Kl at month 3 post-KT could be explained by longer CIT and delayed graft function as well as by impaired graft function. Early SCI may regulate s-Kl increase post-KT.
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The atypical hemolytic-uremic syndrome (aHUS) is characterized by the triad of non-immune hemolytic anemia, thrombocytopenia, and acute renal failure. The aHUS is related to complement dysregulation; since the approval of eculizumab for this entity (a monoclonal antibody that inhibits C5 activation and blocks the formation of the membrane attack complex) the prognosis has improved. The recurrence of aHUS after kidney transplantation is frequent and implies loss of the graft in a high percentage of cases. Eculizumab prophylaxis to prevent recurrence has allowed successful kidney transplantation in this group of patients. We present a series of kidney transplant patients with chronic kidney disease secondary to aHUS and the use of eculizumab for prevention of recurrence.
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Síndrome Hemolítico Urémico Atípico , Trasplante de Riñón , Anticuerpos Monoclonales Humanizados/uso terapéutico , Síndrome Hemolítico Urémico Atípico/tratamiento farmacológico , Inactivadores del Complemento/uso terapéutico , Humanos , Trasplante de Riñón/efectos adversosRESUMEN
Coronavirus disease 2019 (COVID-19) in kidney transplant recipients has a high risk of complications and mortality, especially in older recipients diagnosed during the early period after transplantation. Management of immunosuppression has been challenging during the pandemic. We investigated the impact of induction immunosuppression, either basiliximab or thymoglobulin, on the clinical evolution of kidney transplant recipients developing COVID-19 during the early period after transplantation. We included kidney transplant recipients with Ë6 months with a functioning graft diagnosed with COVID-19 from the initial pandemic outbreak (March 2020) until 31 July 2021 from different Spanish centres participating in a nationwide registry. A total of 127 patients from 17 Spanish centres developed COVID-19 during the first 6 months after transplantation; 73 (57.5%) received basiliximab and 54 (42.5%) thymoglobulin. Demographics were not different between groups but patients receiving thymoglobulin were more sensitized [calculated panel reactive antibodies (cPRAs) 32.7 ± 40.8% versus 5.6 ± 18.5%] and were more frequently retransplants (30% versus 4%). Recipients Ë65 years of age treated with thymoglobulin showed the highest rate of acute respiratory distress syndrome [64.7% versus 37.1% for older recipients receiving thymoglobulin and basiliximab (P < .05), respectively, and 23.7% and 18.9% for young recipients receiving basiliximab and thymoglobulin (P > .05)], respectively, and the poorest survival [mortality rate 64.7% and 42.9% for older recipients treated with thymoglobulin and basiliximab, respectively (P < .05) and 8.1% and 10.5% for young recipients treated with thymoglobulin and basiliximab (P > .05), respectively]. Older recipients treated with thymoglobulin showed the poorest survival in the Cox regression model adjusted for comorbidities. Thus thymoglobulin should be used with caution in older recipients during the present pandemic era.
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BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has especially affected kidney transplant (KT) recipients, who are more vulnerable than the general population because of their immunosuppressive status and added comorbidities. The purpose of this study was to determine risk factors related to infection and mortality from COVID-19 in KT recipients. METHODS: The study included 113 stable KT recipients who had polymerase chain reaction-confirmed COVID-19 infection between March 2020 and February 2021, from a total of 2150 KT recipients. Outcomes related to patient survival were analyzed. RESULTS: The mean (standard deviation) age of the patients was 56 (14) years; 62% (n = 70) were men. The median time between KT and infection was 88 months (interquartile range, 39-155 months); 90% (n = 102) were on tacrolimus therapy and 81% (n = 92) on mycophenolate mofetil. The clinical presentation was pneumonia (n = 57; 51%), fever (n = 61; 54%), cough (n = 62; 55%), dyspnea (n = 43; 38%), lymphopenia (n = 57; 50%), and gastrointestinal symptoms (n = 28; 25%). A total of 21% (n = 24) required intubation and intensive care unit admission, and 27 patients (25%) were asymptomatic. A total of 9% (n = 10) received hydroxychloroquine therapy plus azithromycin, 11% (n = 12) tocilizumab, 3.7% (n = 4) lopinavir/ritonavir, 49% (n = 55) steroids, 0.9% (n = 1) remdesivir, and 9.3% (n = 11) convalescent plasma. Immunosuppression was reduced in all symptomatic patients. Nineteen patients (17%) died. Cox univariate analysis showed that the factors significantly associated with death were patient age, presence of pneumonia or lymphopenia, and elevated C-reactive protein on admission. CONCLUSIONS: Mortality in KT recipients with COVID-19 is very high, more than for the general population. Risk factors are patient age, presence of pneumonia or lymphopenia, and a higher C-reactive protein level at the time of diagnosis.
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COVID-19 , Trasplante de Riñón , COVID-19/terapia , Humanos , Inmunización Pasiva , Trasplante de Riñón/efectos adversos , Masculino , Persona de Mediana Edad , Factores de Riesgo , SARS-CoV-2 , España/epidemiología , Receptores de Trasplantes , Sueroterapia para COVID-19RESUMEN
We determined the association between CD14++CD16+ monocytes and subclinical infiltrates that do not reach the histological threshold for rejection (≥Banff IA). We studied low-immunological-risk kidney-transplant recipients in a clinical trial (NCT02284464; EudraCT 2012-003298-24) whose protocol biopsy in the third month showed no significant changes or borderline lesions (BL). Flow cytometry was used to analyze the percentage of CD14++CD16+ monocytes in peripheral blood (PB) and blood from a fine-needle-aspiration biopsy (FNAB). A protocol biopsy was performed in 81 low-immunological-risk patients, of whom 15 were excluded (BK polyomavirus and rejection). The 28 (42.4%) with borderline lesions had significantly low levels of CD14++CD16+ in PB compared to patients with normal biopsies (7.9 ± 5.4 vs. 13.0 ± 12.8; p = 0.047). Patients without significant changes had similar percentages of CD14++CD16+ monocytes in the graft blood (GB) and FNAB blood. The percentage of these monocytes in the patients with an interstitial infiltrate, however, increased significantly in the FNAB blood compared to the GB: 16.9 ± 16.6 vs. 7.9 ± 5.4; p = 0.006. A difference of 50% in CD14++CD16+ in the GB versus the PB was a significant risk factor (p = 0.002) for BL, increasing the risk seven times. A decrease in CD14++CD16+ in the PB could be associated with the recruitment of these cells to the graft tissue in cases of subclinical BL inflammatory infiltrates below the threshold for rejection.
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BACKGROUND: Few studies have analyzed differences in clinical presentation and outcomes in solid organ transplant (SOT) recipients with coronavirus disease 2019 (COVID-19) across different pandemic waves. METHODS: In this multicenter, nationwide, prospective study, we compared demographics and clinical features, therapeutic management, and outcomes in SOT recipients diagnosed with COVID-19 in Spain before (first wave) or after (second wave) 13 July 2020. RESULTS: Of 1634 SOT recipients, 690 (42.2%) and 944 (57.8%) were diagnosed during the first and second periods, respectively. Compared with the first wave, recipients in the second were younger (median: 63 y [interquartile range, IQR: 53-71] versus 59 y [IQR: 49-68]; P < 0.001) and less likely to receive anti-severe acute respiratory syndrome coronavirus 2 drugs (81.8% versus 8.1%; P < 0.001), with no differences in immunomodulatory therapies (46.8% versus 47.0%; P = 0.931). Adjustment of immunosuppression was less common during the second period (76.4% versus 53.6%; P < 0.001). Hospital admission (86.7% versus 58.1%; P < 0.001), occurrence of acute respiratory distress syndrome (34.1% versus 21.0%; P < 0.001), and case-fatality rate (25.8% versus 16.7%; P < 0.001) were lower in the second period. In multivariate analysis, acquiring COVID-19 during the first wave was associated with an increased risk of death (OR: 1.47; 95% confidence interval [CI], 1.12-1.93; P = 0.005), although this impact was lost in the subgroup of patients requiring hospital (OR: 0.97; 95% CI, 0.73-1.29; P = 0.873) or intensive care unit admission (OR: 0.65; 95% CI, 0.35-1.18; P = 0.157). CONCLUSIONS: We observed meaningful changes in demographics, therapeutic approaches, level of care, and outcomes between the first and second pandemic waves. However, outcomes have not improved in the more severe cases of posttransplant COVID-19.
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COVID-19/terapia , Trasplante de Órganos , SARS-CoV-2 , Anciano , COVID-19/inmunología , COVID-19/mortalidad , Femenino , Humanos , Terapia de Inmunosupresión , Unidades de Cuidados Intensivos , Masculino , Persona de Mediana Edad , Estudios ProspectivosRESUMEN
Atrial fibrillation (AF) represents an important social and healthcare problem. There is wide variability in the prevalence of this arrhythmia in studies analysing patients on haemodialysis (HD). OBJECTIVE: To investigate the prevalence, clinical profile and therapeutic management of patients with AF on HD in Andalusia. METHODS: We asked the public healthcare system of Andalusia to provide us with the number of patients who were being treated with HD. We asked attending nephrologists from all hospital and outpatient centres in 5 of the 8 Andalusian provinces to perform an electrocardiogram and to fill out a questionnaire on patients selected by simple random sampling. RESULTS: A total of 2,348 patients were being treated with HD in the 5provinces included in the study. The estimated sample size was 285 patients. We obtained an electrocardiogram and information from 252 patients (88.4%); mean age 65.3±16 years; 40.9% women. Sixty-three patients (25%) had AF. Of these, 36 (14.3%) had AF in the recorded ECG and in the rest it had been documented previously. In the multivariate analysis, older age (OR: 1.071; 95% CI: 1.036-1.107; P=0.000) and greater time on HD (OR: 1.009; 95% CI: 1.004-1.014; P=0.000) were independently associated with the presence of AF. Of the patients with AF, 41.3% were on anticoagulant treatment at the time of the study; and 41.2% were on antiplatelet agents. CONCLUSIONS: AF in dialysis units is an important finding. Establishing the risk-benefit ratio of anticoagulant treatment constitutes a real challenge. Well-designed clinical trials are pivotal in order to define the rational use of antithrombotic drugs.
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Fibrilación Atrial , Diálisis Renal , Adulto , Anciano , Anciano de 80 o más Años , Anticoagulantes/uso terapéutico , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/epidemiología , Fibrilación Atrial/terapia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Autoinforme , España/epidemiología , Adulto JovenRESUMEN
La fibrilación auricular (FA) es un importante problema social y sanitario. Existe una amplia variación en la prevalencia de esta arritmia en los estudios que analizan a los pacientes en hemodiálisis (HD). OBJETIVO: Investigar la prevalencia, perfil clínico y manejo terapéutico de los pacientes con FA en HD en Andalucía. MÉTODOS: Solicitamos al sistema sanitario público de Andalucía el número de pacientes que estaban siendo tratados con HD. Pedimos a los nefrólogos responsables de todos los centros hospitalarios y extrahospitalarios de 5 de las 8 provincias de Andalucía que realizaran un electrocardiograma y cumplimentaran un cuestionario en pacientes seleccionados por un muestreo aleatorizado simple. RESULTADOS: Estaban en HD 2.348 pacientes en las 5provincias incluidas. El tamaño muestral estimado fue 285 pacientes. Obtuvimos electrocardiograma e información de 252 (88,4%). Edad media 65,3 ± 16 años; 40,9% mujeres. Tenían FA 63 pacientes (25%). De estos, 36 (14,3%) tenían FA en el registro realizado y en el resto había sido documentada previamente. En el análisis multivariante, mayor edad (OR: 1,071; IC 95%: 1,036-1,107; p = 0,000) y mayor tiempo en HD (OR: 1,009; IC 95%:1,004-1,014; p = 0,000) se asociaron de forma independiente con la FA. De los pacientes con FA, el 41,3% estaban en tratamiento anticoagulante en el momento del estudio y el 41,2% con antiagregantes. CONCLUSIONES: La FA en las unidades de diálisis es un importante hallazgo. Establecer la relación riesgo-beneficio del tratamiento anticoagulante constituye un auténtico reto. Son necesarios ensayos clínicos bien diseñados para establecer el uso racional del tratamiento antitrombótico
Atrial fibrillation (AF) represents an important social and healthcare problem. There is wide variability in the prevalence of this arrhythmia in studies analysing patients on haemodialysis (HD). OBJECTIVE: To investigate the prevalence, clinical profile and therapeutic management of patients with AF on HD in Andalusia. METHODS: We asked the public healthcare system of Andalusia to provide us with the number of patients who were being treated with HD. We asked attending nephrologists from all hospital and outpatient centres in 5 of the 8 Andalusian provinces to perform an electrocardiogram and to fill out a questionnaire on patients selected by simple random sampling. RESULTS: A total of 2,348 patients were being treated with HD in the 5provinces included in the study. The estimated sample size was 285 patients. We obtained an electrocardiogram and information from 252 patients (88.4%); mean age 65.3 ± 16 years; 40.9% women. Sixty-three patients (25%) had AF. Of these, 36 (14.3%) had AF in the recorded ECG and in the rest it had been documented previously. In the multivariate analysis, older age (OR: 1.071; 95% CI: 1.036-1.107; P = 0.000) and greater time on HD (OR: 1.009; 95% CI: 1.004-1.014; P = 0.000) were independently associated with the presence of AF. Of the patients with AF, 41.3% were on anticoagulant treatment at the time of the study; and 41.2% were on antiplatelet agents. CONCLUSIONS: AF in dialysis units is an important finding. Establishing the risk-benefit ratio of anticoagulant treatment constitutes a real challenge. Well-designed clinical trials are pivotal in order to define the rational use of antithrombotic drugs