Impact of Interdialytic Intervals on Sudden Cardiac Death in Chronic Kidney Disease Stage 5D Patients on a Twice-Weekly HD Schedule.

Background: End-stage kidney disease patients on maintenance haemodialysis (HD) are prone to increase cardiovascular and non-cardiovascular mortality in long and short interdialytic intervals of an intermittent thrice-weekly schedule. Variations in fluid and electrolyte status during and in dialysis-free periods may predispose patients to Sudden Cardiac Death (SCD). We studied SCD in HD in relation to the interdialytic interval in patients on a twice-weekly HD schedule.

Method: An ambispective cohort study was done and data of HD patients on twice-weekly schedule were collected from January 2009 to December 2017. Primary outcome was cardiovascular mortality and secondary outcome was estimate of standard mortality ratio (SMR) at each 12-hour (h) period interval of the HD schedule. Deaths were categorized as Sudden Cardiac Death, non-Sudden Cardiac Death, and non-Cardiac Death as per standard definitions.

Results: Of 413 participants, 289 died. The rates of Cardiovascular death accounted for 121 (42%), and non-cardiac death was 168 (58.1%) respectively SCD was the most common cardiovascular event, accounting for 83 (28.7%) of overall mortality. SCD is more likely to occur in the first 12 hours after dialysis following the 3 days long interdialytic interval (SMR: 2.04) and in the 12 hours before the next dialysis session after a short interval (SMR: 1.74).

Conclusion: Occurrence of SCD was higher at two different time points, i.e. 12h period from starting with the dialysis procedure and 12 h period before the start of the next session of HD at the end of a short interval.