We present an observational study to evaluate a progressive schedule of dose of dialysis, starting with 2 HD/week, when the renal clearance of urea was equal to or greater than 2,5？mL/min/1,73？m2 and the patient is in a stable clinical situation. From 2006 to 2011, 182 patients started hemodialysis in our center, of which 134 were included in the study. Residual renal function (RRF), Kt/V, eKru, nPCR, hemoglobin, weekly erythropoietin dose, and beta-2-microglobulin were determined at 6, 12, 18, 24, and 30 months after dialysis initiation. Seventy patients (52%) began with the progressive schedule of 2 HD/week and 64 (48%) patients began with the conventional thrice-weekly schedule (3 HD/week). The decline of RRF was lower in the group of 2 HD/week: 0,20 (0,02–0,53) versus 0,50 (0,14–1,08)？mL/min/month (median and interquartile range, ). No relationship was found between the decline rate and the basal RRF. Survival analysis did not show differences between both groups. Our experience demonstrates that patients with higher residual renal function may require less than conventional 3 HD sessions per week at the start of dialysis. Twice-weekly hemodialysis schedule is safe and cost-effective and may have additional benefit in maintaining the residual renal function. 1. Introduction Dialysis dose in chronic patients treated with peritoneal dialysis is calculated using the sum of peritoneal clearance and residual renal function (RRF). Frequently, the peritoneal dialysis units start the treatment with a low peritoneal dose that is gradually increased afterwards to compensate the decline of RRF [1–4]. This incremental dialysis strategy is uncommon in hemodialysis units where it is habitual to start dialysis with the conventional thrice-weekly schedule (3 HD/week). In 1985, Gotch and Keen  used the urea kinetic model to establish the fact that an adequate dialysis dose could be obtained using two sessions per week (2 HD/week) if renal clearance of urea was equal to or greater than 2,5？mL/min. However, although RRF is present in many patients starting hemodialysis, the 2 HD/week schedule has been scarcely considered. In 2006, we established an incremental dialysis regimen at the start of renal replacement therapy, starting with 2 HD/week in such patients with higher residual renal function, considered a renal clearance urea equal to or greater than 2,5？mL/min. In a previous study we observed that the loss of glomerular filtration rate was lower in patients on the 2 HD/week regimen . We present our 6 years of experience using this pattern with the aim of
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