Constipation in Peritoneal Dialysis Patients

[Nutrition for patients on dialysis]

Dietary recommendations for patients on dialysis are changing as our understanding of enteral microbiotal metabolism and bioavailability of nutrients from food improves.A diet low in phosphate and potassium is recommended for patients on hemodialysis. However, the absolute content does not reflect bioavailability: How much phosphate or potassium is taken up depends on food source (plant vs. animal) and to which grade it is processed. While both are nearly 100% bioavailable from industrially processed foods (additives such as dipotassium-phosphate and other salts), a much lower proportion is taken up from unprocessed plant foods high in fibre (ca. 20-40%). The DIET-HD study showed no significant association between dietary potassium and serum potassium in > 8 000 dialysis patients; and those with the highest low-processed, fresh plant-food consumption have the best survival. Dietary fibre improves colon transit time and thereby lessens symptoms of constipation. A diet low in sodium improves blood pressure and volume management in dialysis patients. The energy and protein requirements on dialysis are high: 25-35 kcal and 1-1,2 g protein per kg body weight per day (in relation to "ideal" body weight, if patient is overweight). Protein energy wasting is associated with higher stages of kidney disease, and malnutrition is associated with worse survival on dialysis. Nutritional status should be assessed on a regular basis using validated scores, and malnutrition should be addressed and treated.

Nursing management of catheter-related non-infectious complications of PD: Your questions answered

A review from the last seven years (August 2016-July 2023) of questions posted to the International Society for Peritoneal Dialysis (ISPD) website "Questions about PD" by nurses and physicians from around the world revealed that 19 of the questions were associated with optimal approaches for preventing, assessing, and managing issues related to PD catheter non-infectious complications. Our review focused on responses to these questions whereby existing best practice recommendations were considered, if available, relevant literature was cited and differences in international practices discussed. We combined similar questions, revised both the original questions and responses for clarity, as well as updated the references to these questions. PD catheter non-infectious complications can often be prevented or, with early detection, the potential severity of the complication can be minimized. We suggest that the PD nurse is key to educating the patient on PD about PD catheter non-infectious complications, promptly recognize a specific complication and bring that complication to the attention of the Home Dialysis Team. The questions posted to the ISPD website highlight the need for more education and resources for PD nurses worldwide on the important topic of non-infectious complications related to PD catheters, thereby enabling us to prevent such complications as PD catheter malfunction, peri-catheter leakage and infusion or drain pain, as well as recognize and resolve these issues promptly when they do arise, thus allowing patients to extend their time on PD therapy and enhance their quality of life whilst on PD.

Complications of Peritoneal Dialysis Part I: Mechanical 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. However, it can be associated with unexpected interruptions to or discontinuation of therapy. Timely diagnosis and resolution are required to minimize preventable modality change to hemodialysis. This review covers mechanical complications, including leaks, PD hydrothorax, hernias, dialysate flow problems, PD-related pain, and changes in respiratory mechanics. Most mechanical complications occur early, either as a result of PD catheter insertion or the introduction of dialysate and consequent increased intra-abdominal pressure. Late mechanical complications can also occur and may require different treatment.

Dietary Patterns, Dietary Adequacy and Nutrient Intake in Adults Commencing Peritoneal Dialysis: Outcomes from a Longitudinal Cohort Study

(1) Background: Optimal dietary intake is integral to good health in people receiving peritoneal dialysis (PD). We investigated how dietary patterns, dietary adequacy and nutrient intake may change over time in people commencing PD. (2) Methods: Participants were attending the PD training unit for the commencement of peritoneal dialysis, aged ≥18 years and willing to complete food records. Misreporters were excluded from the analysis. Dietary intake was compared at PD commencement and at 12 months. Intake was also compared to reference standards. Dietary patterns were derived using principal component analysis. (3) Results: There were no significant changes between baseline and 12 months for grains, fruit, vegetables and meat. Dairy and added sugar intake was significantly lower (p = 0.01). The intake of energy and protein was adequate and did not change. There was a significant reduction in dietary phosphorus and calcium, and increased vitamin C intake. Three dietary patterns were identified: the 'Bread and Cereal' pattern; 'Milk and Potatoes' pattern; and the 'Semi Vegetarian' pattern. (4) Conclusions: In this longitudinal cohort study, the diet quality was suboptimal and there were limited changes in intake after the commencement of PD. Further exploration of how dietary patterns may impact outcomes and quality of life is warranted.

Effects of Tiaopi Xiezhuo decoction on constipation and gut dysbiosis in patients with peritoneal dialysis

CONTEXT

A Chinese herbal formula, Tiaopi Xiezhuo decoction (TXD), is developed from a classical Chinese prescription Sanhuang Xiexin decoction.

OBJECTIVE

To investigate the regulatory effect of TXD on gut dysbiosis, as a treatment of constipation in patients with peritoneal dialysis (PD).

MATERIALS AND METHODS

The chemical content of TXD was assessed by high-performance liquid chromatography. A total of 29 PD patients were enrolled and treated with TXD orally (3 g crude drug/each/twice/day) for 3 months. Blood and faecal samples were collected at the beginning and end, to determine the changes in biochemical characteristics and gut microbial composition. The stool conditions were asked to be scored. Additional 30 healthy individuals were recruited as a control for the analysis of gut microbiota.

RESULTS

Although having no significant effects on serum biochemical characteristics, 3-month TXD intervention improved constipation in PD patients: decreased 80% abdominal distention (p < 0.01), increased 2.6-fold sloppy stools (p < 0.05) and eliminated hard stool completely (p < 0.01). The analysis of gut microbiota showed that, compared to the healthy group, the microbial richness was reduced in PD patients. After a 3-month TXD treatment, this reduced richness was raised, and Paraprevotella clara, Lachnospiraceae bacterium 2-146FA, Phascolarctobaterium succinatutens, Lachnospiraceae bacterium 2-1-58FAA, Fusobacterium mortiferum, and Prevotella copri were accumulated in the intestinal flora. Furthermore, the bacterial species enriched by TXD correlated with the improvement of constipation.

DISCUSSION AND CONCLUSIONS

TXD treatment may improve constipation by modulating gut dysbiosis in PD patients. These findings provide data to support the further application of TXD in the adjuvant treatment of PD.

Gutted: constipation in children with chronic kidney disease and on dialysis

Functional constipation is a common problem in otherwise healthy children. Children with chronic kidney disease (CKD) and on dialysis have additional disease-related risk factors including the uremic milieu, fluid and dietary restrictions, and decreased physical activity, as well as treatment-related risk factors such as dialysis therapy and polypharmacy that contribute to and compound the problem. Constipation causes significant distress for children and their caregivers. In children on peritoneal dialysis, severe constipation can impede catheter function and ultrafiltration. Accumulating evidence points to a possible bidirectional relationship between constipation and CKD, potentially mediated by gut dysbiosis with consequent increased generation of gut-derived uremic toxins and disruption of intestinal epithelium integrity leading to translocation of noxious luminal contents into the circulation inducing systemic inflammation. Effective management of constipation is required but there is little published data on the safety and effectiveness of treatments in adults or children with CKD. In this review, we discuss the diagnosis and epidemiology of functional constipation, provide an overview of its pathophysiology, summarize the therapeutic management, and reflect on the challenges in children with CKD.

Delivering Personalized, Goal-Directed Care to Older Patients Receiving Peritoneal Dialysis

Background

An aging population living with chronic kidney disease and progressing to kidney failure, subsequently receiving peritoneal dialysis (PD) is growing. A significant proportion of these patients are also living with multi-morbidities and some degree of frailty. Recent practice recommendations from the International Society of Peritoneal Dialysis advocate for high-quality, goal-directed PD prescription, and the Standardized Outcomes of Nephrology-PD initiative emphasized the need for an individualized, goal-based care approach in all patients receiving PD treatment. In older patients, this approach to PD care is even more important. A frailty screening assessment, followed by a comprehensive geriatric assessment (CGA) prior to PD initiation and when dictated by change in relevant circumstances is paramount in tailoring PD care and prescription according to the needs, life goals, as well as clinical status of older patients with kidney failure.

Summary

Our review aimed to summarize the different dimensions to be taken into account when delivering PD care to the older patient - from frailty screening and CGA in older patients receiving PD to employing a personalized, goal-directed PD prescription strategy, to preserving residual kidney function, optimizing blood pressure (BP) control, and managing anemia, to addressing symptom burden, to managing nutritional intake and promoting physical exercise, and to explore telehealth opportunities for the older PD population.

Key Messages

What matters most to older PD patients may not be simply extending survival, but more importantly, to be living comfortably on PD treatment with minimal symptom burden in a home environment and to minimize treatment complications.

The value of preventing constipation in patients treated with peritoneal dialysis: an advanced practice nursing study

Introduction

In 1989, experts developed the Rome criteria classification coupled with the use of the Bristol scale, to objectify the condition of functional constipation.Background Nowadays, little is documented in the literature about transit disorders in patients with End-Stage Chronic Renal Failure treated with peritoneal dialysis, even though this causes non-negligible complications on the patient’s morbidity, comfort and quality of life.

Objective

The main objective of our study was to evaluate the prevalence of constipation in CKD patients.

Material and method

We conducted a retrospective multicenter data-driven study.

Results

74 patient records were analyzed. We found a prevalence of constipation of 58 % in patients with CKD.

Discussion

Our results showed that the prevalence of constipation is frequent in patients with CKD. It leads to a significant discomfort for the patient, an additional cost in terms of care and technical procedures and a failure of the peritoneal dialysis technique.

Conclusion

Thus, the prevention of constipation in CKD patients would be relevant to limit complications and ensure a better quality of life.

Range and consistency of gastrointestinal outcomes reported in peritoneal dialysis trials: A systematic review

BACKGROUND

Gastrointestinal (GI) health is considered vital to the success of peritoneal dialysis (PD) and is critically important to patients, caregivers and clinicians. However, the multiplicity of GI outcome measures in trials undermines the ability to evaluate the frequency, impact and treatment of GI symptoms in patients receiving PD. Therefore, this study aimed to assess the range and consistency of GI outcomes reported in contemporary PD trials.

STUDY DESIGN

Systematic review.

SETTING AND POPULATION

Individuals with kidney failure requiring PD.

SELECTION CRITERIA

All randomised controlled trials involving patients on PD, identified from the PUBMED, EMBASE and COCHRANE Central Registry of controlled Trials (CENTRAL) database, from January 2010 to July 2022.

INTERVENTIONS

Any PD-related intervention.

OUTCOMES

The frequency and characteristics of GI outcome measures were analysed and classified.

RESULTS

Of the 324 eligible PD trials, GI outcomes were only reported in 61 (19%) trials, mostly as patient-reported outcomes (45 trials; 74%). The most frequently reported outcomes were nausea in 27 (43%), diarrhoea in 26 (43%), vomiting in 22 (36%), constipation in 21 (34%) and abdominal pain in 19 (31%) of trials. PD peritonitis was the primary non-GI outcome reported in 24 (40%) trials, followed by death in 13 (21%) trials) and exit-site infection in 9 (15%) trials). Across all trials, 172 GI outcome measures were extracted and grouped into 29 different outcomes. Nausea and diarrhoea contributed to 16% and 15% of GI outcomes, respectively, while vomiting, constipation and abdominal pain contributed to 13%, 12% and 12%, respectively. Most (90%) GI outcomes were patient-reported adverse effects with no defined metrics. Faecal microbiome was reported as the primary study outcome in 3 (100%) trials using the subjective global assessment score, GI symptom rating scale and faecal microbiological and biochemical analysis. Two trials reported nausea as a primary study outcome using symptom assessment score (SAS) and kidney disease quality of life-short-form-36. One trial each reported anorexia and abdominal pain as the primary study outcome using SAS. Bowel habits, constipation and stool type were also reported as the primary study outcome in one trial each using the Bristol stool form scale. GI bleeding was reported as the secondary outcome in three (37%) out of eight trials reporting it.

LIMITATIONS

Restricted sampling frame to focus on contemporary trials.

CONCLUSIONS

Despite the clinical importance of GI outcomes among patients on PD, they are reported in only 19% of PD trials, using inconsistent metrics, often as patient-reported adverse events. Efforts to standardise GI outcome reporting are critical to optimising comparability, reliability and value of trial evidence to improve outcomes for patients receiving PD.

Epidemiology of peritoneal dialysis outcomes

Peritoneal dialysis (PD) is an important home-based treatment for kidney failure and accounts for 11% of all dialysis and 9% of all kidney replacement therapy globally. Although PD is available in 81% of countries, this provision ranges from 96% in high-income countries to 32% in low-income countries. Compared with haemodialysis, PD has numerous potential advantages, including a simpler technique, greater feasibility of use in remote communities, generally lower cost, lesser need for trained staff, fewer management challenges during natural disasters, possibly better survival in the first few years, greater ability to travel, fewer dietary restrictions, better preservation of residual kidney function, greater treatment satisfaction, better quality of life, better outcomes following subsequent kidney transplantation, delayed need for vascular access (especially in small children), reduced need for erythropoiesis-stimulating agents, and lower risk of blood-borne virus infections and of SARS-CoV-2 infection. PD outcomes have been improving over time but with great variability, driven by individual and system-level inequities and by centre effects; this variation is exacerbated by a lack of standardized outcome definitions. Potential strategies for outcome improvement include enhanced standardization, monitoring and reporting of PD outcomes, and the implementation of continuous quality improvement programmes and of PD-specific interventions, such as incremental PD, the use of biocompatible PD solutions and remote PD monitoring.

The use of peritoneal dialysis (PD) can be advantageous compared with haemodialysis treatment, although several barriers limit its broad implementation. This review examines the epidemiology of peritoneal dialysis (PD) outcomes, including clinical, patient-reported and surrogate PD outcomes.

Peritoneal dialysis (PD) has distinct advantages compared with haemodialysis, including the convenience of home treatment, improved quality of life, technical simplicity, lesser need for trained staff, greater cost-effectiveness in most countries, improved equity of access to dialysis in resource-limited settings, and improved survival, particularly in the first few years of initiating therapy.

Important barriers can hamper PD utilization in low-income settings, including the high costs of PD fluids (owing to the inability to manufacture them locally and the exorbitant costs of their import), limited workforce availability and a practice culture that limits optimal PD use, often leading to suboptimal outcomes.

PD outcomes are highly variable around the world owing in part to the use of variable outcome definitions, a heterogeneous practice culture, the lack of standardized monitoring and reporting of quality indicators, and kidney failure care gaps (including health care workforce shortages, inadequate health care financing, suboptimal governance and a lack of good health care information systems).

Key outcomes include not only clinical outcomes (typically defined as medical outcomes based on clinician assessment or diagnosis) — for example, PD-related infections, technique survival, mechanical complications, hospitalizations and PD-related mortality — but also patient-reported outcomes. These outcomes are directly reported by patients and focus on how they function or feel, typically in relation to quality of life or symptoms; patient-reported outcomes are used less frequently than clinical outcomes in day-to-day routine care.

Influence of peritoneal dialysis catheter type on dislocations and laxative use: a retrospective observational study

Background

There is currently no consensus regarding the optimal type of peritoneal dialysis (PD) catheter. Although few studies showed that weighted catheters result in lower complication rates and superior long-term outcomes than non-weighted catheters, there are no studies on the use of laxatives linked to catheter malfunction, a patient-related outcome potentially affecting the quality of life. Thus, we compared the burden of acute and chronic laxative use in a cohort of PD patients having either weighted or non-weighted catheters.

Methods

We performed a single-center, retrospective, observational study in two renal units, comparing acute and chronic laxative therapy related to catheter drainage failure in a cohort of 74 PD patient,s divided by peritoneal dialysis catheter type. In addition, we evaluated the number of patients who experienced minor and major dislocations, catheter-related infection rate, hospitalization for catheter malfunctioning, episodes of catheter repositioning, and dropout from PD.

Results

Laxative use was significantly more common among patients in the non-weighted catheter group (acute: 30.3% vs. 9.8%, p = 0.03; chronic: 36.4% vs. 12.2%; p≤0.02). Furthermore, weighted catheters were superior to non-weighted catheters for all the secondary outcomes (dislocations: 12.2% vs. 45.5%; p = 0.001).

Conclusions

Weighted self-locating catheters have lower drainage failure, thus reducing the need and burden of acute and chronic laxative use among PD patients.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s40620-022-01329-6.

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.

Patient-reported gastrointestinal symptoms in patients with peritoneal dialysis: the prevalence, influence factors and association with quality of life

Background

The aims of this study were to investigate the prevalence and the influence factors of gastrointestinal symptoms, and its association with the quality of life (QOL) in peritoneal dialysis (PD) patients.

Methods

Continuous ambulatory PD patients (CAPD) who followed up in our PD center between March 2016 and December 2017 were enrolled in this cross-sectional study. Gastrointestinal symptom rating scale (GSRS) was used to evaluate gastrointestinal symptoms. The related clinical data were also collected. Multiple linear regression analysis was test for the influence factors associated with score of GSRS and QOL.

Results

This study included 471 CAPD patients. The mean age was 48.5±13.9 years, 53.9% were male and 15.1% with diabetic nephropathy. The median duration of PD was 37.3 (17.5~66.5) months. The median score of GSRS was 1.2(1.1~1.3) scores. Totally 82.2% (n=387) CAPD patients had at least one gastrointestinal symptom. Higher glycosylated hemoglobin, higher score of depression, lower diastolic blood pressure, urine output, score of instrumental activities of daily living scale and more amount of pills per day were independently associated with higher score of GSRS (all P<0.05). Score of dyspepsia and eating dysfunction were independently associated with worse score of QOL and physical health (all P<0.05).

Conclusions

Gastrointestinal symptoms were common but not serious in CAPD patients. Glycemic control, depression, blood pressure, urine output, activity of daily life and amount of pills were all associated with gastrointestinal symptoms. Moreover, gastrointestinal symptoms were correlated with QOL of PD patients.

Patient Selection and Planning for Image-Guided Peritoneal Dialysis Catheter Placement

Image-guided percutaneous peritoneal dialysis (PD) catheter insertion has become increasingly relied upon to provide urgent access for late presenting kidney failure patients, to overcome surgical backlogs and limited operating room access, to avoid general anesthesia in high-risk patients, and, by itself, as an alternative approach to surgical PD access. Advanced planning for the procedure is essential to assure the best possible outcome. Appropriate selection of patients for percutaneous PD catheter placement, choosing the most suitable catheter type, determining insertion and exit site locations, and final patient preparations facilitate the performance of the procedure, minimizes the risk of complications, and improves the likelihood of providing a successful long-term peritoneal access.

Smoking is a Risk Factor for Endogenous Peritonitis in Patients Undergoing Peritoneal Dialysis

BACKGROUND

Peritonitis is one of the most common complications in patients undergoing peritoneal dialysis, (PD) but it is difficult to predict or prevent. In this study, we analyzed the risk of endogenous peritonitis in patients receiving PD.

METHODS

We included all patients who underwent PD at our hospital from April 2015 to March 2020. There were 22 cases of peritonitis, including 18 cases of endogenous peritonitis without evidence of exit-site infection or technical failure. We evaluated older age, female sex, obesity, diabetes, diverticulosis, and constipation as potential important risk factors for endogenous peritonitis and included these as confounding factors, along with a current or previous history of smoking, in univariate logistic regression models.

RESULTS

A previous or current history of smoking (p = 0.0065) was the most significant risk factor for endogenous peritonitis in the univariate logistic regression model. In addition, smoking was the most significant independent risk factor for endogenous peritonitis (p = 0.0034) in multivariate logistic regression models. Diabetes was also significant in univariate and multivariate logistic regression analysis.

CONCLUSIONS

Smoking is a significant independent risk factor for endogenous peritonitis in patients undergoing PD. Cessation of smoking may lower the risk of endogenous peritonitis in this patient group.

Lower Limb Ulcer Associated with Peritonitis in Patients Undergoing Peritoneal Dialysis

Purpose

Peritoneal dialysis (PD)-related peritonitis and lower limb ulcer are the important complications in patients undergoing PD. Although the association between lower limb ulcer and peritonitis in patients undergoing PD is unclear, based on our clinical experience and the clinical importance of the complications in patients undergoing PD, we hypothesized that lower limb ulcer is associated with peritonitis in patients on PD.

Patients and Methods

In this single center, retrospective cohort study, we studied 87 patients who started undergoing PD at our hospital from April 2015 to March 2020. We compared these 8 patients with lower limb ulcer with the other 79 patients without lower limb ulcer. We compared between the patients in the objection period of this study about peritonitis using Log rank test, and used the unpaired t-test and Fisher’s exact test to compare the clinical factors between the two groups. Moreover, we used univariate and multivariate logistic regression analyses to study the association of PD-related peritonitis with the clinical factors.

Results

The period developed first peritonitis of the patients on PD with lower limb ulcer was significant shorter than those without lower limb ulcer in Log rank test (P = 0.011). The Fisher’s exact test and unpaired t-test showed that the difference in the prevalence of PD-related peritonitis (P = 0.009), peritonitis/patient years (P = 0.036), the BMI (P = 0.007) and icodextrin (P = 0.001) were significant. Lower limb ulcer had significant associations with peritonitis in patients on PD in both univariate [odds ratio (OR) 8.461, 95% confidence interval (CI) 1.854–45.60, P = 0.006] and multivariate [OR 7.169, 95% CI 1.519–39.480, P = 0.013] logistic regression analysis.

Conclusion

In conclusion, lower limb ulcer may be associated with peritonitis in patients undergoing PD. Further large-scale, prospective studies are required to confirm these results.

Assisted peritoneal dialysis and transfer to haemodialysis: a cause-specific analysis with data from the RDPLF

Background

Technique failure, defined as death or transfer to haemodialysis (HD), is a major concern in peritoneal dialysis (PD). Nurse-assisted PD is globally associated with a lower risk of transfer to HD. We aimed to evaluate the association between assisted PD and the risk of the different causes of transfer to HD.

Methods

This was a retrospective study using data from the French Language PD Registry of patients on incident PD from 2006 to 2015. The association between the use of assisted PD and the causes of transfer to HD was evaluated using survival analysis with competing events in unmatched and propensity score-matched cohorts.

Results

The study included 11 093 incident PD patients treated in 123 French PD units. There were 4273 deaths, 3330 transfers to HD and 2210 renal transplantations. The causes of transfer to HD were inadequate dialysis (1283), infection (524), catheter-related problems (334), social issues (250), other causes linked to PD (422), other causes not linked to PD (481) and encapsulating peritoneal sclerosis (6). Nurse-assisted PD patients were older and more comorbid. Assistance by nurse was associated with a higher risk of death [cause-specific hazard ratio (cs-HR) 2.49, 95% confidence interval (CI) 2.26–2.74], but with a lower risk of transfer to HD [subdistributionHR (sd-HR) 0.68, 95% CI 0.62–0.76], especially due to inadequate dialysis (cs-HR 0.83, 95% CI 0.75–0).

Conclusions

The lower risk of transfer to HD associated with nurse assistance should encourage decision makers to launch reimbursement programmes in countries where it is not available.

Constipation in CKD

Constipation is one of the most common gastrointestinal disorders among patients with chronic kidney disease (CKD) partly because of their sedentary lifestyle, low fiber and fluid intake, concomitant medications (e.g., phosphate binders), and multiple comorbidities (e.g., diabetes). Although constipation is usually perceived as a benign, often self-limited condition, recent evidence has challenged this most common perception of constipation. The chronic symptoms of constipation negatively affect patients' quality of life and impose a considerable social and economic burden. Furthermore, recent epidemiological studies have revealed that constipation is independently associated with adverse clinical outcomes, such as end-stage renal disease (ESRD), cardiovascular (CV) disease, and mortality, potentially mediated by the alteration of gut microbiota and the increased production of fecal metabolites. Given the importance of the gut in the disposal of uremic toxins and in acid-base and mineral homeostasis with declining kidney function, the presence of constipation in CKD may limit or even preclude these ancillary gastrointestinal roles, potentially contributing to excess morbidity and mortality. With the advent of new drug classes for constipation, some of which showing unique renoprotective properties, the adequate management of constipation in CKD may provide additional therapeutic benefits beyond its conventional defecation control. Nevertheless, the problem of constipation in CKD has long been underrecognized and its management strategies have scarcely been documented. This review outlines the current understanding of the diagnosis, prevalence, etiology, outcome, and treatment of constipation in CKD, and aims to discuss its novel clinical and therapeutic implications.