Study Population and Procedures
nausea, light-headedness, cramping, hyperkalemia, hypotension
SPin-D enrolled 129 participants who met the following inclusion criteria: age 18–85 years and treatment with maintenance HD for >6 months or for 3–6 months if there were no changes in target dry weight during the prior 2 weeks and no hospitalizations during the previous 6 weeks. Notable exclusion criteria included serum potassium concentration ≥6.5 mEq/L or unscheduled dialysis for hyperkalemia within 3 months; serum potassium concentration ≥6.0 mEq/L within 2 weeks before baseline; pre-HD systolic blood pressure <100 mm Hg within 2 weeks before screening or at baseline; ≥2 dialysis sessions within the month before screening with blood pressure <80 mm Hg or treatment for cramping, light-headedness, nausea, or hypotension; use of digoxin, spironolactone, or eplerenone; or dual use of angiotensin-converting enzyme inhibitors and angiotensin receptor blockers.A protocol amendment was added on January 22, 2016, after 64 patients had enrolled in the trial to include optional cardiac monitoring during trial participation. A subset of 57 patients consented to undergo seven days of continuous heart rate and rhythm monitoring using a wearable patch (SEEQ Mobile Cardiac Telemetry System; Medtronic, Minneapolis, MN) before randomization, at week 6, and during weeks 32–36. Thirty (53%) of the 57 participants completed electrocardiographic monitoring at all three time points.