Hypokalemia and hyperkalemia in patients on peritoneal dialysis: incidence and associated factors

Hypokalemia in Peritoneal Dialysis: A Systematic Review and Meta-analysis of Prevalence, Treatment, and Outcomes

Rationale & Objective

Hypokalemia is common and potentially life-threatening in patients undergoing peritoneal dialysis (PD). However, the current literature has produced varying results. This study aimed to evaluate the prevalence and adverse outcomes of hypokalemia and the role of potassium supplementation in patients receiving PD.

Study Design

Systematic review and meta-analysis of randomized controlled trials and observational studies.

Setting & Study Populations

Adults receiving maintenance PD.

Selection Criteria for Studies

Studies that investigated the prevalence and adverse outcomes of hypokalemia and the effect of potassium supplementation.

Data Extraction

Two independent reviewers evaluated studies for eligibility and extracted relevant data.

Analytical Approach

Random effects meta-analysis was conducted to pool hazard ratios (HRs) and 95% CIs for the outcomes of interest. The certainty of findings was rated according to the Grading of Recommendations Assessment, Development and Evaluation criteria.

Results

Of 3,632 reports identified, 24 studies involving 60,313 participants met the inclusion criteria. The prevalence of hypokalemia was 37.9% (95% CI, 27.2%-52.7%), 17.7% (95% CI, 12.0%-25.9%), and 4.4% (95% CI, 1.9%-10.2%) in patients with potassium level <4.0, 3.5, and 3.0 mmol/L, respectively. Hypokalemia, according to the study's definition, was associated with increased risks of all-cause mortality (HR, 1.49; 95% CI, 1.18-1.89), cardiovascular mortality (HR, 1.50; 95% CI, 1.19-1.88), and PD-associated peritonitis (HR, 1.42; 95% CI, 1.17-1.73). These associations were consistent but with low to very low certainty. The effect of correcting hypokalemia with potassium supplementation in patients undergoing PD remains uncertain.

Limitations

Heterogeneity persisted across most of the examined subgroups, and observational studies preclude causation.

Conclusions

Hypokalemia is common and portends poorer survival and a higher risk of peritonitis among patients undergoing PD. Further research into the optimal prevention and treatment strategies for hypokalemia is warranted to improve outcomes.

Registration

Registered at PROSPERO with registration number CRD42022358236.

Higher Platelet Count Mostly in the Normal Range Is Associated with the First Episode of Peritonitis Risk in Incident Peritoneal Dialysis Patients

INTRODUCTION

Platelets play parts in infection and immune processes. However, the association between platelet count and the risk of peritoneal dialysis (PD)-associated peritonitis is unclear.

METHODS

This was a retrospective, observational, single-center cohort study. A Cox regression analysis was used to evaluate the independent association of platelet count with the occurrence of first PD-associated peritonitis. Models were adjusted for gender, age, body mass index, cardiovascular disease, diabetes mellitus, white blood cell count, neutrophil-lymphocyte ratio, hemoglobin level, albumin level, potassium level, and anti-platelet medication usage.

RESULTS

A total of 2,374 patients were enrolled in this study (59% men; mean age 47.40 ± 12.12). The average platelet count was 229.30 ± 82.12 × 109/L. 467 (20%) patients suffered from PD-associated peritonitis at least once. In the multivariable model, the adjusted hazard ratios (HRs) for quartiles 2, 3 and 4 versus quartile 1 were 1.428 (95% CI 1.060-1.924, p = 0.019), 1.663 (95% CI 1.240-2.229, p < 0.001) and 1.843 (95% CI 1.363-2.492, p < 0.001) with baseline data. A nonlinear relationship between platelet count and first PD-associated peritonitis was observed. Further, the association between platelet and first PD-associated peritonitis was significant in the patients with hypokalemia (P for interaction = 0.040).

CONCLUSION

In PD patients, elevated platelet counts were significantly associated with an increased risk of the first onset of PD-associated peritonitis.

Association between serum potassium, risk and prognosis of peritonitis in peritoneal dialysis patients - results from the Peritoneal Dialysis Telemedicine-assisted Platform Cohort (PDTAP) Study

BACKGROUND

Hypokalemia has been associated with an increased risk of peritoneal dialysis (PD)-associated peritonitis. However, hypokalemia is commonly associated with malnutrition, inflammation, and severe coexisting comorbidities, which thus are suspected of being potential confounders. This study was aimed at testing whether hypokalemia was independently associated with the occurrence and prognosis of PD-associated peritonitis.

METHODS

A national-level dataset from the Peritoneal Dialysis Telemedicine-assisted Platform Cohort (PDTAP) Study was used to explore the independent association of serum potassium with PD-associated peritonitis. Unmatched and propensity score-adjusted multivariate competing risk models, as well as univariate competing risk models following 1:1 propensity score matching, were conducted to balance potential biases between patients with and without hypokalemia. The association between potassium levels prior to peritonitis and treatment failure due to peritonitis was also investigated.

RESULTS

During a median follow-up of 25.7 months in 7220 PD patients, there was a higher incidence of peritonitis in patients with serum potassium below 4.0 mmol/L compared to those with higher serum levels (677 [0.114/patient-year] vs. 914 [0.096/patient-year], P = 0.001). After adjusting for demographics, laboratory tests, residual renal function, and medication use, baseline potassium levels below 4.0 mmol/L were not linked to an increased risk of peritonitis, with a hazard ratio of 0.983 (95% CI 0.855-1.130, P = 0.810). This result remained consistent in both the propensity score adjusted multivariate competing risk regression (HR = 0.974, 95% CI 0.829-1.145, P = 0.750) and the univariate competing risk regression after 1:1 propensity score matching (Fine-Gray test, P = 0.218). The results were similar when analyzing patients with serum potassium level above or below 3.5 mmol/L. Lastly, hypokalemia before the occurrence of peritonitis was not independently associated with treatment failure.

CONCLUSION

Hypokalemia was not found to be an independent risk factor for PD-associated peritonitis or treatment failure of peritonitis in China.

Complications of Peritoneal Dialysis Part II: Nonmechanical Complications

Peritoneal dialysis (PD) is a form of KRT that offers flexibility and autonomy to patients with ESKD. It is associated with lower costs compared with hemodialysis in many countries. Unlike mechanical complications that typical arise early in the course of treatment, noninfectious, nonmechanical complications often present late in patients who are established on PD. In this review, we first discuss abnormal-appearing drained dialysate, including hemoperitoneum, chyloperitoneum, and noninfectious cloudy dialysate. The underlying cause is frequently unrelated to PD. We then discuss encapsulating peritoneal sclerosis, a rare complication of PD. Finally, we review metabolic changes associated with PD and methods to mitigate its effects.

Dietary knowledge-attitude-practice status in hemodialysis patients: a latent profile analysis

BACKGROUND

Hemodialysis patients require a reasonable dietary intake to manage their disease progression effectively. However, there is limited research on these patients' overall dietary knowledge, attitude, and practice (KAP) status. This study aimed to investigate the dietary KAP status and latent profiles in hemodialysis patients and identify sociodemographic and disease-related factors associated with these profiles and dietary practice.

METHODS

A multicenter cross-sectional study involving 425 hemodialysis patients was conducted. A dietary KAP questionnaire in hemodialysis patients was used to evaluate the dietary KAP of the patients. A structural equation model was employed to analyze the correlations between dietary knowledge, attitude, and practice. Multiple linear regression analysis was used to identify factors associated with dietary practice scores. Latent profile analysis was conducted to determine the latent profiles of dietary KAP, and binary logistic regression was used to explore the sociodemographic and disease-related characteristics associated with each KAP profile in hemodialysis patients.

RESULTS

The normalized average scores for dietary knowledge, attitude, and practice in hemodialysis patients were 0.58, 0.82, and 0.58, respectively. The structural equation model revealed significant positive correlations between dietary knowledge and attitude, and attitude and practice. Attitude played an indirect effect between knowledge and practice. Gender, cerebrovascular disease, and dietary attitude scores were identified as independent influencing factors for dietary practice scores. Two dietary KAP profiles were developed: a profile with general knowledge and attitude but low practice (40.2%) and a profile with general knowledge and attitude and high practice (59.8%). Binary logistic regression analysis indicated gender and monthly income per household significantly predicted membership in each KAP profile.

CONCLUSIONS

The dietary practice of hemodialysis patients requires improvement. It is necessary to develop more individualized dietary interventions for these patients. Further exploration is needed to understand the motivation of patients to change their dietary behavior.

Increase in peritoneal dialysis-related hospitalization rates after telemedicine implementation during the COVID-19 pandemic

Introduction and objectives

To minimize our peritoneal dialysis (PD) population exposure to coronavirus disease (COVID-19), in April 2020 we developed and implemented a telemedicine program. In this investigation, we aimed to compare the hospitalization rates and metabolic disorders in patients undergoing PD 6 months before and after the COVID-19 pandemic and telemedicine implementation.

Materials and methods

This single-center retrospective analysis included all active prevalent patients undergoing PD from April 2020. Dialysis records were reviewed to obtain clinical, demographic, laboratory, appointment, and hospitalization data. We compared hospitalization rates (total, non-PD-related, and PD-related), hospitalization-associated factors, and metabolic disorders (hemoglobin, serum potassium, and serum phosphate) 6 months before and after the pandemic.

Results

Our sample comprised 103 participants. During the pre-pandemic and post-pandemic periods, there were 13 and 27 hospital admissions, respectively. The total hospitalization incident rate ratio (IRR) was 2.48 (95% confidence interval [CI], 1.29-4.75). PD-related hospitalizations increased from 3 to 15 episodes (IRR = 7.25 [95% CI, 2.11-24.78]). In the pre-pandemic period, the educational level was lower in participants hospitalised due to PD-related issues than in participants not hospitalised. In the post-pandemic period, only sex distribution differed between patients not hospitalised and those hospitalised due to non-PD-related issues. Only serum potassium levels changed significantly in the post-pandemic period (4.79 ± 0.48 vs. 4.93 ± 0.54 mg/dL; P < 0.01).

Conclusion

This study showed a significant increase in hospitalization rates after the COVID-19 pandemic period and telemedicine implementation, mainly due to PD-related infectious causes. Strategies to improve distance monitoring assistance are needed for the PD population.

Hypokalemia Duration in the First Year Associated with Subsequent Peritoneal Dialysis-Associated Peritonitis: A Multicenter Retrospective Cohort Study

BACKGROUND

The association of hypokalemia (LK) with peritoneal dialysis-associated peritonitis (PDAP) risk remains uncertain. Here, we calculated LK duration in the first PD year and evaluated its association with PDAP.

METHODS

A multicenter, retrospective, incident cohort study of 1633 participants was conducted from January 2008 to October 2020 in China. The duration of LK and severe hypokalemia (SLK) was calculated as the total number of months that a patient's serum potassium (SK) level was less than 3.5 or 3.0 mEq/L during the first PD year. The study outcome was the risk of subsequent PDAP started in the second year and later. Cox proportional hazards models and competing risk models were used to assess the association.

RESULTS

The subsequent PDAP occurred in 420 (25.7%) participants during a median of 28 months of follow-up. Overall, LK duration in the first year was positively associated with a subsequent PDAP risk (per 3-month increments, adjusted HR, 1.13; 95%CI: 1.05-1.23). After categorization, patients with LK duration longer than 6 months had the highest adjusted HR of 1.53 (p = 0.005 vs. those without LK) for subsequent PDAP risk. A similar trend was also found for SLK duration. In a competing risk model, a similar trend was also observed. None of the variables, including demographic and PD characteristics, diabetes history, and several clinical measurements, significantly modified this association. The causative organisms of PDAP were similar to those previously reported.

CONCLUSIONS

PD patients with longer LK duration in the first year had a higher subsequent PDAP risk.

Increase in peritoneal dialysis-related hospitalization rates after telemedicine implementation during the COVID-19 pandemic

INTRODUCTION AND OBJECTIVES

To minimize our peritoneal dialysis (PD) population exposure to coronavirus disease (COVID-19), in April 2020 we developed and implemented a telemedicine program. In this investigation, we aimed to compare the hospitalization rates and metabolic disorders in patients undergoing PD 6 months before and after the COVID-19 pandemic and telemedicine implementation.

MATERIALS AND METHODS

This single-center retrospective analysis included all active prevalent patients undergoing PD from April 2020. Dialysis records were reviewed to obtain clinical, demographic, laboratory, appointment, and hospitalization data. We compared hospitalization rates (total, non-PD-related, and PD-related), hospitalization-associated factors, and metabolic disorders (hemoglobin, serum potassium, and serum phosphate) 6 months before and after the pandemic.

RESULTS

Our sample comprised 103 participants. During the pre-pandemic and post-pandemic periods, there were 13 and 27 hospital admissions, respectively. The total hospitalization incident rate ratio (IRR) was 2.48 (95% confidence interval [CI], 1.29-4.75). PD-related hospitalizations increased from 3 to 15 episodes (IRR=7.25 [95% CI, 2.11-24.78]). In the pre-pandemic period, the educational level was lower in participants hospitalised due to PD-related issues than in participants not hospitalised. In the post-pandemic period, only sex distribution differed between patients not hospitalised and those hospitalised due to non-PD-related issues. Only serum potassium levels changed significantly in the post-pandemic period (4.79±0.48 vs. 4.93±0.54mg/dL; P<0.01).

CONCLUSION

This study showed a significant increase in hospitalization rates after the COVID-19 pandemic period and telemedicine implementation, mainly due to PD-related infectious causes. Strategies to improve distance monitoring assistance are needed for the PD population.

Hyperkalemia in Chronic Kidney Disease: Links, Risks and Management

Hyperkalemia is a common clinical problem with potentially fatal consequences. The prevalence of hyperkalemia is increasing, partially due to wide-scale utilization of prognostically beneficial medications that inhibit the renin-angiotensin-aldosterone-system (RAASi). Chronic kidney disease (CKD) is one of the multitude of risk factors for and associations with hyperkalemia. Reductions in urinary potassium excretion that occur in CKD can lead to an inability to maintain potassium homeostasis. In CKD patients, there are a variety of strategies to tackle acute and chronic hyperkalemia, including protecting myocardium from arrhythmias, shifting potassium into cells, increasing potassium excretion from the body, addressing dietary intake and treating associated conditions, which may exacerbate problems such as metabolic acidosis. The evidence base is variable but has recently been supplemented with the discovery of novel oral potassium binders, which have shown promise and efficacy in studies. Their use is likely to become widespread and offers another tool to the clinician treating hyperkalemia. Our review article provides an overview of hyperkalemia in CKD patients, including an exploration of relevant guidelines and nuances around management.

Reproductive Consequences of Electrolyte Disturbances in Domestic Animals

Electrolyte balance is essential to maintain homeostasis in the body. The most crucial electrolytes are sodium (Na+), potassium (K+), magnesium (Mg2+), chloride (Cl−), and calcium (Ca2+). These ions maintain the volume of body fluids, and blood pressure, participate in muscle contractions, and nerve conduction, and are important in enzymatic reactions. The balance is mainly ensured by the kidneys, which are an important organ that regulates the volume and composition of urine, together with which excess electrolytes are excreted. They are also important in the reproductive system, where they play a key role. In the male reproductive system, electrolytes are important in acrosomal reaction and sperm motility. Sodium, calcium, magnesium, and chloride are related to sperm capacitation. Moreover, Mg2+, Ca2+, and Na+ play a key role in spermatogenesis and the maintenance of morphologically normal spermatozoa. Infertility problems are becoming more common. It is known that disturbances in the electrolyte balance lead to reproductive dysfunction. In men, there is a decrease in sperm motility, loss of sperm capacitation, and male infertility. In the female reproductive system, sodium is associated with estrogen synthesis. In the contraction and relaxation of the uterus, there is sodium, potassium, and calcium. Calcium is associated with oocyte activation. In turn, in women, changes in the composition of the follicular fluid are observed, leading to a restriction of follicular growth. Imbalance of oocyte electrolytes, resulting in a lack of oocyte activation and, consequently, infertility.

Plant-Based Diets and Peritoneal Dialysis: A Review

Whole food plant-based diets are gaining popularity as a preventative and therapeutic modality for numerous chronic health conditions, including chronic kidney disease, but their role and safety in end-stage kidney disease patients on peritoneal dialysis (PD) is unclear. Given the general public's increased interest in this dietary pattern, it is likely that clinicians will encounter individuals on PD who are either consuming, considering, or interested in learning more about a diet with more plants. This review explores how increasing plant consumption might affect those on PD, encompassing potential benefits, including some specific to the PD population, and potential concerns.

Degree and duration of hypokalemia associated with peritonitis in patients undergoing peritoneal dialysis

BACKGROUND

Hypokalemia (LK) was associated with peritonitis in peritoneal dialysis (PD) patients, while the role of its degree and duration have not been fully established. Here, we conducted a retrospective cohort study to identify the relationships of LK degree and duration with peritonitis in PD patients.

METHODS

A total of 602 PD patients in our department from Jan 1st, 2009 to Dec 31st, 2019 entered the last analysis. Data were collected from their medical records. Serum potassium (SK) levels, degree of hypokalemia, and duration of hypokalemia were analysed with peritonitis. The time association of hypokalemia and peritonitis was also analysed.

RESULTS

There were totally 320 (53.7%) and 123 (20.7%) patients who had ever suffered from LK and serious hypokalemia (SLK) in the cohort. Only 6.82% and 0.5% of patients had LK and SLK at baseline, while the incidence increased and kept in 25%-32% and 5.5%-8.2% after PD. Both LK (HR 1.437, 95% CI 1.014-2.038, P = .042) and SLK (HR 2.021, 95% CI 1.429-2.857, P < .001) did correlate to peritonitis after adjusted analyses, while only SLK remained the significance at each follow-up point. The LK/SLK durations were 6 (3-12) and 6 (3-6) months, and only longer SLK duration correlated with peritonitis after adjusted analyses. After categorised, those LK durations more than 6 months and SLK durations more than 3 months presented a significant association with peritonitis. Of the patients who suffered from both hypokalemia and peritonitis, 70.4% patients' LK times were earlier than peritonitis time, while most SLK times (62.7%) were later. SLK also correlated with combined endpoint.

CONCLUSIONS

Hypokalemia degree and duration were tightly associated with peritonitis. Hypokalemia might be a causal factor of peritonitis, while peritonitis might also aggravate hypokalemia. We should manage SK as much as possible and avoid hypokalemia, especially serious hypokalemia in clinic practice.

Increased colonic K+ excretion through inhibition of the H,K-ATPase type 2 helps reduce plasma K+ level in a murine model of nephronic reduction

Hyperkalemia is frequently observed in patients at the end-stage of chronic kidney disease (CKD), and has possible harmful consequences on cardiac function. Many strategies are currently used to manage hyperkalemia, one consisting of increasing fecal K⁺ excretion through the administration of cation-exchange resins. In this study, we explored another more specific method of increasing intestinal K⁺ secretion by inhibiting the H,K-ATPase type 2 (HKA2), which is the main colonic K⁺ reabsorptive pathway. We hypothetised that the absence of this pump could impede the increase of plasma K⁺ levels following nephronic reduction (N5/6) by favoring fecal K⁺ secretion. In N5/6 WT and HKA2KO mice under normal K⁺ intake, the plasma K⁺ level remained within the normal range, however, a load of K⁺ induced strong hyperkalemia in N5/6 WT mice (9.1 ± 0.5 mM), which was significantly less pronounced in N5/6 HKA2KO mice (7.9 ± 0.4 mM, p < 0.01). This was correlated to a higher capacity of HKA2KO mice to excrete K⁺ in their feces. The absence of HKA2 also increased fecal Na⁺ excretion by inhibiting its colonic ENaC-dependent absorption. We also showed that angiotensin-converting-enzyme inhibitor like enalapril, used to treat hypertension during CKD, induced a less severe hyperkalemia in N5/6 HKA2KO than in N5/6 WT mice. This study therefore provides the proof of concept that the targeted inhibition of HKA2 could be a specific therapeutic maneuver to reduce plasma K⁺ levels in CKD patients.