Abstract:
BACKGROUND: Hypokalemia is the most common electrolyte abnormality in patients on peritoneal dialysis (PD) and has been associated with increased risks of peritonitis and fatality. Whether systematic correction of hypokalemia could improve these outcomes has never been explored. METHODS: In this multicenter, open-label, prospective, randomized controlled trial, PD patients with hypokalemia (defined as at least 3 values or an average value <3.5 mEq/L in the past 6 months) were randomized to receive either protocol-based potassium treatment (titratable dose of oral potassium chloride to maintain serum potassium 4-5 mEq/L) or conventional potassium treatment (reactive supplementation when serum potassium <3.5 mEq/L) over 52 weeks. Randomization was stratified according to centre and residual urine output (≤100 or >100 mL/day). The primary outcome was time from randomization to peritonitis. Secondary outcomes were all-cause mortality, cardiovascular mortality, hospitalization, and hemodialysis transfer. RESULTS: A total of 167 patients with time-average serum potassium concentrations of 3.33±0.28 mEq/L were enrolled from 6 Thai PD centers: 85 were assigned to receive protocol-based treatment and 82 were assigned to conventional treatment. Median follow-up time was 11.6 months. During the study period, serum potassium level in the protocol group increased to 4.04±0.62 mEq/L at 4 weeks and remained at 4.36±0.70 mEq/L compared with 3.57±0.65 mEq/L in patients with conventional treatment (mean difference 0.66, 95% confidence interval [CI], 0.53 to 0.79 mEq/L, p<0.001). The incidence of PD-related peritonitis was lower significantly in the protocol group than in the conventional group (15.3% vs 29.3%; hazard ratio 0.47, 95% CI, 0.24-0.93, p=0.029). There were no significant between-group differences in any of the secondary outcomes. Hyperkalemia (>6 mEq/L) occurred in 3 patients with protocol-based treatment (3.5%). There was 1 peritonitis-related death in the conventional group. CONCLUSIONS: Protocol-based oral potassium treatment to maintain serum potassium concentration in the range of 4-5 mEq/L significantly reduces the risk of peritonitis in hypokalemic PD patients compared with reactive potassium supplementation when serum potassium falls below 3.5 mEq/L.