Risk of Hypokalemia to the First Episode Peritonitis Related to Peritoneal Dialysis

Objective: To determine whether hypokalemia is a risk factor for first episode peritonitis among patients undergoing peritoneal dialysis (PD) Material and Methods: A retrospective cohort study was conducted among PD patients treated at Nakornping Hospital, Chiang Mai, Thailand, between January 2007 and September 2013. The subjects were divided into two groups according to their time-averaged serum potassium concentrations: <3.5 mEq/L (hypokalemia) versus 3.5-5.5 mEq/L (normokalemia). Cox’s proportional-hazards regression analysis was used to determine relationship between hypokalemia and the first episode of PD-related peritonitis. Results: Of 342 eligible PD patients with follow-up assessments, 184 (53.8%) had PD-related peritonitis. Coagulase-negative staphylococci (CoNS) (12.5%) and Staphylococcus aureus (6.5%) were isolated more frequently in the first episode of PD-related peritonitis. The incidence of the first episode of PD-related peritonitis for the hypokalemia and normokalemia groups were 0.48 and 0.31 episodes per person-years, respectively. From the Cox’s proportional-hazards model, the hypokalemia group had a higher risk of first episode of PD-related peritonitis compared with the normokalemia group [adjusted HR (hazard ratio) 1.42; 95% CI (confidence interval)=1.02-1.98, p-value=0.039]. Conclusion: In PD patients, hypokalemia was an independent risk factor for first episode PD-related peritonitis. Potassium replacement therapy should be administered when appropriate to reduce the rate of first episode PD-related peritonitis. Serum potassium levels should be closely monitored in patients with PD.