Laxatives Lower Risk of Hyperkalemia in Advanced Chronic Kidney Disease

The researchers included a total of 36,116 United States mostly male veterans with advanced CKD. Using generalized estimating equations with adjustment for potential confounders, they examined the association of time-varying laxative use with risk of dyskalemia (i.e., hypokalemia [potassium <3.5 mEq/L] or hyperkalemia [>5.5 mEq/L]) versus normokalemia (3.5–5.5 mEq/L) over the 1-year pre-ESKD period. Among 36,116 veterans, they noted 15,842 (5.0%) had hyperkalemia and 12,787 (4.0%) had hypokalemia in the year prior to end-stage kidney disease (ESKD).

Key findings of the study were:

• Over the last 1-year pre-ESKD period, the researchers identified 319,219 repeated potassium measurements in the cohort.
• Among 319,219 readings, they noted hypokalemia in 4.0% and hyperkalemia in 5.0% with the time-averaged potassium measurement of 4.5 mEq/L.
• Upon multivariable adjustment, they found that time-varying laxative use was significantly associated with 21% lower adjusted odds of hyperkalemia (serum potassium greater than 5.5 mEq/L) compared with nonuse.
• However, they found no relationship between laxative use and hypokalemia (serum potassium less than 3.5 mEq/L).
• They further noted that the results were consistent with several sensitivity analyses.

The authors concluded, " Laxative use was independently associated with lower risk of hyperkalemia during the last 1-year pre-ESKD period. Our findings support a putative role of constipation in potassium disarrays and also support (with a careful consideration for the risk-benefit profiles) the therapeutic potential of laxatives in hyperkalemia management in advanced CKD."

For further information:

https://jasn.asnjournals.org/content/32/4/950