Ramipril and Cardiovascular Outcomes in Patients on Maintenance Hemodialysis: The ARCADIA Multicenter Randomized Controlled Trial.

BACKGROUND AND OBJECTIVES: Renin-angiotensin system (RAS) inhibitors reduce cardiovascular morbidity and mortality in patients with CKD. We evaluated the cardioprotective effects of the angiotensin-converting enzyme inhibitor ramipril in patients on maintenance hemodialysis. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: In this phase 3, prospective, randomized, open-label, blinded end point, parallel, multicenter trial, we recruited patients on maintenance hemodialysis with hypertension and/or left ventricular hypertrophy from 28 Italian centers. Between July 2009 and February 2014, 140 participants were randomized to ramipril (1.25-10 mg/d) and 129 participants were allocated to non-RAS inhibition therapy, both titrated up to the maximally tolerated dose to achieve predefined target BP values. The primary efficacy end point was a composite of cardiovascular death, myocardial infarction, or stroke. Secondary end points included the single components of the primary end point, new-onset or recurrence of atrial fibrillation, hospitalizations for symptomatic fluid overload, thrombosis or stenosis of the arteriovenous fistula, and changes in cardiac mass index. All outcomes were evaluated up to 42 months after randomization. RESULTS: At comparable BP control, 23 participants on ramipril (16%) and 24 on non-RAS inhibitor therapy (19%) reached the primary composite end point (hazard ratio, 0.93; 95% confidence interval, 0.52 to 1.64; P=0.80). Ramipril reduced cardiac mass index at 1 year of follow-up (between-group difference in change from baseline: -16.3 g/m2; 95% confidence interval, -29.4 to -3.1), but did not significantly affect the other secondary outcomes. Hypotensive episodes were more frequent in participants allocated to ramipril than controls (41% versus 12%). Twenty participants on ramipril and nine controls developed cancer, including six gastrointestinal malignancies on ramipril (four were fatal), compared with none in controls. CONCLUSIONS: Ramipril did not reduce the risk of major cardiovascular events in patients on maintenance hemodialysis. CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER: ARCADIA, NCT00985322 and European Union Drug Regulating Authorities Clinical Trials Database number 2008-003529-17.

Morpho-functional study of peritoneum in peritoneal dialysis patients.

BACKGROUND: Structure and function of the peritoneal membrane (PM) are impaired on peritoneal dialysis (PD). The aim of this study was to examine the relationship between dialytic parameters and histological and functional characteristics of the peritoneum of PD patients. METHODS: A peritoneal biopsy (PB) was performed on 31 PD patients during catheter removal due to malfunction or after drop-out from treatment. PB was performed at least 5 cm from the catheter insertion. For each patient PM transport was evaluated by the last peritoneal equilibration test (PET) before PB. Each daily glucose load was calculated. Tissue was formalin-embedded and stained for histological and immunohistochemical studies. RESULTS: (1) Duration of treatment was longer in patients with mesothelial impairment. (2) Patients showing sub-mesothelial sclerosis (SS) and those with impairment of submesothelial basement membrane and subendothelial vascular membrane (SVM) were submitted to a larger daily glucose load. (3) SS exceeding 50 mm was more frequent among high transporters, who were exposed to larger daily glucose load compared to medium-high transporters. (4) Mesothelial loss correlated to SS and vascular alterations. (5) SS was related to vascular injuries but not to inflammatory infiltrate. CONCLUSIONS: SS is not constant in PD patients and is not a prominent factor in treatment drop-out. Mesothelial impairment seems to be mainly related to duration of PD treatment. Glucose load seems to mainly damage the sub-mesothelial layer.