Hyperkalemia excursions are associated with an increased risk of mortality and hospitalizations in hemodialysis patients

Abstract

Background Hyperkalemia is common among hemodialysis (HD) patients and has been associated with adverse clinical outcomes. Previous studies considered a single serum potassium (K) measurement or time-averaged values, but serum K excursions out of the target range may be more reflective of true hyperkalemia events. We assessed whether hyperkalemia excursions lead to an elevated risk of adverse clinical outcomes. Methods Using data from 21 countries in Phases 4–6 (2009–18) of the Dialysis Outcomes and Practice Patterns Study (DOPPS), we investigated the associations between peak serum K level, measured monthly predialysis, over a 4-month period (‘peak K’) and clinical outcomes over the subsequent 4 months using Cox regression, adjusted for potential confounders. Results The analysis included 62 070 patients contributing a median of 3 (interquartile range 2–6) 4-month periods. The prevalence of hyperkalemia based on peak K was 58% for >5.0, 30% for >5.5 and 12% for >6.0 mEq/L. The all-cause mortality hazard ratio for peak K (reference ≤5.0 mEq/L) was 1.15 [95% confidence interval (CI) 1.09, 1.21] for 5.1–5.5 mEq/L, 1.19 (1.12, 1.26) for 5.6–6.0 mEq/L and 1.33 (1.23, 1.43) for >6.0 mEq/L. Results were qualitatively consistent when analyzing hospitalizations and a cardiovascular composite outcome. Conclusions Among HD patients, we identified a lower K threshold (peak K 5.1–5.5 mEq/L) than previously reported for increased risk of hospitalization and mortality, with the implication that a greater proportion (>50%) of the HD population may be at risk. A reassessment of hyperkalemia severity ranges is needed, as well as an exploration of new strategies for effective management of chronic hyperkalemia.

Serum potassium variability as a predictor of clinical outcomes in patients with cardiorenal disease or diabetes: a retrospective UK database study

“…The current study also demonstrated that increased sK + variability may be a risk factor for MACE compared with low sK + variability, independent of the absolute sK + concentration; this is consistent with a recent study demonstrating that HK excursions are associated with mortality, hospitalizations and cardiovascular events in patients receiving haemodialysis [ 26 ]. It should be noted that no association between sK + variability and adverse outcomes was seen in patients on dialysis in the present study; however, the dialysis cohort was comparatively small, which led to wide CIs, limiting the conclusions that could be drawn.…”

“…One recent study showed that a proportion of patients suffer frequently recurrent HK events [ 22 ], potentially leading to patients spending a high proportion of their time in an HK state. Other previous studies of patients in the intensive care unit (ICU) or receiving dialysis have demonstrated that increased sK + variability is associated with increased mortality [ 23–25 ], while another study in patients receiving haemodialysis demonstrated an association between HK excursions and adverse clinical outcomes [ 26 ]. This study aimed to explore the impact of length of time spent in an HK state, defined by thresholds of sK + 5.0, ≥5.5 or 6.0 mmol/L, on adverse clinical outcomes and to investigate sK + variability as a risk factor for adverse clinical outcomes independent of mean sK + in real-world cohorts of patients with cardiorenal conditions and diabetes.…”

High prevalence of hyperkalemia in Brazilian chronic dialysis patients and differences across geographic regions

“…The results of the DOPPS study showed that serum potassium above 6.0 mEq/L increased arrhythmia by 21% and all-cause mortality by 12 to 33%. 9,17 Our results should raise the awareness of the nephrology community to this common life-threatening condition.…”

Nutritional potassium limitation impact on serum potassium change, and death in chronic kidney disease: A meta‐analysis

“…A total of 1021 distinctive studies were found, of which eight studies (between 1998 and 2021) satisfied the inclusion criteria and were comprised in the study [26][27][28][29][30][31][32][33]. The eight studies included 92 558 subjects with chronic kidney disease at the start of the study; 41 474 of them were provided with nutritional potassium limitation and 510 084 were nonrestricted diet.…”