Dyskalemias Before Dialysis Increases Risk of Post-Dialysis mortality

Both hyperkalemia and hypokalemia are associated with an increased risk of mortality, adverse clinical outcomes, and increased economic burden in patients with NDD-CKD. Although the association of dyskalemias with mortality has been well studied in NDD-CKD, the relationship of plasma K variability with mortality is unclear. Therefore, a research team of America, conducted a study, to assess the association between K variability before dialysis initiation with mortality after dialysis initiation.

Researchers assessed longitudinal data from the Transition of Care in Chronic Kidney Disease, a nationally representative historic cohort of US veterans with incident end-stage renal disease transitioning to dialysis from 1, October 2007 through 31, March 2015. They identified a total of 34,167 US veterans with at least 1 K measurement each year over 3 years before transition (3-year prelude). For each patient, they used a linear mixed-effects model, to regress K over time (in years) over the 3-year prelude to derive K variability. The major outcomes assessed were 6-month all-cause and cardiovascular mortality after dialysis initiation.

They categorized the potassium variability in the following quartiles:

• less than 0.31,
• 0.31 and higher but less than 0.41,
• 0.41 and higher but less than 0.52, and
• 0.52 mEq/L or more.

Upon analysis, they found that higher prelude K variability was associated with higher multivariable-adjusted risk of all-cause mortality, but not cardiovascular mortality (adjusted hazard/sub hazards ratios [95% confidence interval] for highest quartile [vs lowest] of K variability, 1.14 and 0.99 for all-cause and cardiovascular mortality, respectively).

The authors concluded, "a higher K variability before dialysis initiation (especially K variability measured in the last year before dialysis initiation) is associated with an increased risk of mortality in incident dialysis patients. Thus, higher K variability may serve as a clinically important prognostic marker for future clinical events."

For further information:

https://www.kireports.org/article/S2468-0249(20)31778-2/fulltext