Physical Symptom Cluster Subgroups in Chronic Kidney Disease

Symptom profiles in patients receiving maintenance hemodialysis and their association with quality of life: a longitudinal study

PURPOSE

Many patients receiving maintenance hemodialysis experience one or multiple symptoms. Using a latent profile analysis to identify symptom profiles may provide insights for person-centered symptom management strategies.

METHODS

This is a longitudinal study based on data from patients receiving maintenance hemodialysis at three hospitals in Shanghai, China. Of the 448 patients who completed the surveys at baseline (T1), 309 completed the 12-month follow-up survey (T2). Symptoms and quality of life were measured by the Chinese version of Kidney Disease Quality of Life 36 Short Form. The optimal classification of symptoms was identified using latent profile analysis.

RESULTS

Five symptom profiles were identified: High (9.2%), Fatigue and Gastrointestinal (7.1%), Fatigue and Skin (10.7%), Skin (23.2%), and Low (49.8%). The high-symptom profile and the-fatigue-and-skin-symptom profile were associated with a lower level of physical functioning, a higher burden of kidney disease, and more negative effects of kidney disease than the low symptom profile at T1 and T2. Multivariate regression analysis showed that the high-symptom profile predicted a poorer physical functioning at T2, and the-fatigue-and-skin-symptom profile predicted a poorer physical functioning and higher burden of kidney disease at T2.

CONCLUSION

Patients receiving maintenance hemodialysis reported unique symptom experiences which could be classified into different profiles. Patients reporting an overall high level of symptoms or a high level of fatigue and skin symptoms were more likely to have a poorer quality of life.

The Heterogeneity of Symptom Burden and Fear of Progression Among Kidney Transplant Recipients: A Latent Class Analysis

Purpose

Kidney transplant recipients (KTRs) may experience symptoms that increase their fear of progression (FoP), but a dearth of research examines the issue from a patient-centered perspective. Our study aimed to first determine the category of symptom burden, then to explore the differences in characteristics of patients in different subgroups, and finally to analyze the impact of symptom subgroup on FoP.

Patients and Methods

Sociodemographic and Clinical Characteristics, Symptom Experience Scale, and Fear of Progression Questionnaire-Short Form were used. Latent class analysis was used to group KTRs according to the occurrence of symptoms. We used multivariate logistic regression to analyze the predictors of different subgroups. The differences in FoP among symptom burden subgroups were analyzed by hierarchical multiple regression.

Results

Three subgroups were identified, designated all-high (20.5%), moderate (39.9%), and all-low (39.6%) according to their symptom occurrence. Multivariate logistic regression showed that gender, post-transplant time, per capita monthly income, and hyperuricemia were the factors that distinguished and predicted the all-high subgroup (P < 0.05). Hierarchical multiple regression showed that symptom burden had a significant effect on FoP (class1 vs class3: β = 0.327, P < 0.001; class2 vs class3: β = 0.104, P = 0.046), explaining the 8.0% variance of FoP (ΔR2 = 0.080).

Conclusion

KTRs generally experience moderate or low symptom burden, and symptom burden is an influencing factor in FoP. Identifying the traits of KTRs with high symptom burden can help clinicians develop targeted management strategies and ease FoP of KTRs.

Symptom Science in Kidney Disease

Physical and emotional symptoms are highly prevalent among patients with kidney disease and are directly linked to impaired health-related quality of life. Symptom science is a field of research aimed at advancing knowledge of the holistic mechanisms driving symptoms, how best to assess symptoms accurately, and developing novel and patient-centered approaches to symptom management. Patients with kidney disease have identified symptom science as a top research priority, and opportunities abound for ongoing patient engagement in symptom-related research efforts and clinical care. This review describes the burden of symptoms experienced by patients with kidney disease, explores the spectrum of patient engagement in symptom care and research, and discusses approaches for symptom assessment and management, taking into consideration the multitude of factors that may contribute to symptoms.

Obstacles to Early Diagnosis and Treatment of Pruritus in Patients with Chronic Kidney Disease: Current Perspectives

Chronic kidney disease-associated pruritus (CKD-aP) is a common condition amongst patients with advanced chronic kidney disease (CKD). Several studies have confirmed that more than four out of ten early-stage CKD patients suffer from this condition, while its prevalence among CKD patients on dialysis reaches up to seven out of ten. It is noted to be associated with other disabling symptoms and serious outcomes. It has significant impact on sleep, mood, daily activities, and quality of life of CKD patients, and increased mortality risk of patients on hemodialysis. The Dialysis Outcomes and Practice Patterns Study found 17% higher mortality among patients with moderate to extreme pruritus compared with patients with no or mild pruritus. Despite its high prevalence, ill-effect, and suffering associated with it, CKD-aP remains surprisingly under-reported on the patient's part and under-recognized by the healthcare team. Even upon being noticed, it remains unattended and poorly treated. Its etiopathogenesis is complex and not fully understood. Many treatment options are available but good quality evidence about most of those is absent, and to date, only two medications are approved for use in this condition. While a validated guideline is very much required for the benefit of the patients and caretakers, further research on several aspects of this issue is required.

Five-Year Symptom Trajectories in Nondialysis-Dependent CKD Patients

BACKGROUND AND OBJECTIVES

Late stages of CKD are characterized by significant symptom burden. This study aimed to identify subgroups within the 5-year trajectories of symptom evolution in patients with CKD and to describe associated patient characteristics and outcomes.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Among 2787 participants (66% men) with eGFR <60 ml/min per 1.73 m2 enrolled in the CKD-Renal Epidemiology and Information Network (CKD-REIN) cohort study from July 2013 to May 2016, we assessed symptoms annually using the Kidney Disease Quality of Life-36 (KDQOL-36) questionnaire until December 2020. A total of 9121 measures were reported over follow-up; all participants had symptoms scored for at least one time point. We used a joint latent class-mixed model to distinguish profiles of symptom trajectories.

RESULTS

Patient mean age (±SD) at baseline was 67±13 years, and mean eGFR was 33±13 ml/min per 1.73 m2. The prevalence of each symptom ranged from 24% (chest pain) to 83% (fatigue), and 98% of participants reported at least one symptom. After a median (interquartile range) follow-up of 5.3 (3.4-6.0) years, 690 participants initiated KRT, and 490 died before KRT. We identified two profiles of symptom trajectories: a "worse symptom score and worsening trajectory" in 31% of participants, characterized by a low initial symptom score that worsened more than ten points over time, and a "better symptom score and stable trajectory" in 69% of participants, characterized by a high initial score that remained stable. Participants in the worse symptom score and worsening trajectory group had more risk factors for CKD progression at baseline, worse quality of life, and a higher risk of KRT and death before KRT than other participants.

CONCLUSIONS

This study highlights a significant worsening of symptoms in about one third of the participants, whereas the majority reported low symptom severity throughout the study.

Latent Profile/Class Analysis Identifying Differentiated Intervention Effects

BACKGROUND

The randomized clinical trial is generally considered the most rigorous study design for evaluating overall intervention effects. Due to patient heterogeneity, subgroup analysis is often used to identify differential intervention effects. In research of behavioral interventions, such subgroups often depend on a latent construct measured by multiple correlated observed variables.

OBJECTIVES

The purpose of this article is to illustrate latent class analysis/latent profile analysis as a helpful tool to characterize latent subgroups, conduct exploratory subgroup analysis, and identify potential differential intervention effects using clinical trial data.

METHODS

After reviewing different approaches for subgroup analysis, latent class analysis/latent profile analysis was chosen to identify heterogeneous patient groups based on multiple correlated variables. This approach is superior in this specific scenario because of its ability to control type I error, assess intersection of multiple moderators, and improve interpretability. We used a case study example to illustrate the process of identifying latent classes as potential moderators based on both clinical and perceived risk scores and then tested the differential effects of health coaching in improving health behavior for patients with elevated risk of developing coronary heart disease.

RESULTS

We identified three classes based on one clinical risk score and four perceived risk measures for individuals with high risk of developing coronary heart disease. Compared to other classes we assessed, individuals in the class with low clinical risk and low perceived risk benefit most from health coaching to improve their physical activity levels.

DISCUSSION

Latent class analysis/latent profile analysis offers a person-centered approach to identifying distinct patient profiles that can be used as moderators for subgroup analysis. This offers tremendous opportunity to identify differential intervention effects in behavioral research.

Trajectories of Uremic Symptom Severity and Kidney Function in Patients with Chronic Kidney Disease

BACKGROUND AND OBJECTIVES

Uremic symptoms, including fatigue, anorexia, pruritus, nausea, paresthesia, and pain, are attributed to the accumulation of organic waste products normally cleared by the kidneys, but whether kidney function is the primary driver of changes in symptom severity over time is not known. The goal of our study was to evaluate the association between eGFR and uremic symptom severity score in patients with CKD.

DESIGN, SETTING, PARTICIPANTS, AND MEASUREMENTS

We identified 3685 participants with CKD not on dialysis in the prospective, observational Chronic Renal Insufficiency Cohort (CRIC) Study with baseline assessment of eGFR and uremic symptom severity. Symptoms were assessed by separate questions on the Kidney Disease Quality of Life-36 instrument (zero- to 100-point scale). The longitudinal association between eGFR and uremic symptom severity score was examined with multivariable adjusted linear mixed-effects models with random intercepts and random slopes.

RESULTS

The mean±SD eGFR at baseline was 44±15 ml/min per 1.73 m2, and participants had a median of six (interquartile range 3-11) simultaneous assessments of eGFR and uremic symptoms over the duration of follow-up. The most prevalent symptoms at baseline were pain (57%), fatigue (52%), paresthesia (45%), and pruritus (42%). In adjusted models, a decrease in eGFR of 5 ml/min per 1.73 m2 was associated with a worsening of the symptom severity score by two points or less for each uremic symptom (P<0.01; zero- to 100-point scale). The association between eGFR and uremic symptom severity score was nonlinear. When starting from a lower initial eGFR, a 5 ml/min per 1.73 m2 decrease in eGFR was associated with a greater magnitude of uremic symptom worsening.

CONCLUSIONS

The prevalence of uremic symptoms in CKD is high, with significant variability in patient symptom change over time. Declines in eGFR were associated with worsening of uremic symptom severity, but the magnitude of these changes is small and of uncertain clinical significance.

Patient-centred approaches for the management of unpleasant symptoms in kidney disease

Patients with chronic kidney disease (CKD) frequently experience unpleasant symptoms. These can be gastrointestinal (constipation, nausea, vomiting and diarrhoea), psychological (anxiety and sadness), neurological (lightheadedness, headache and numbness), cardiopulmonary (shortness of breath and oedema), dermatological (pruritus and dry skin), painful (muscle cramps, chest pain and abdominal pain) or involve sexual dysfunction, sleep disorders and fatigue. These symptoms often occur in clusters, with one of them as the lead symptom and others as secondary symptoms. Uraemic toxins (also called uremic toxins) are often considered to be the main cause of CKD-associated symptom burden, but treatment of uraemia by dialysis often fails to resolve them and can engender additional symptoms. Indeed, symptoms can be exacerbated by comorbid conditions, pharmacotherapies, lifestyle and dietary regimens, kidney replacement therapy and ageing. Patients with kidney disease, including those who depend on dialysis or transplantation, should feel actively supported in their symptom management through the identification and targeting of unpleasant symptoms via a tailored palliative care approach. Such an approach may help minimize the burden and consequences of kidney disease, and lead to improved patient outcomes including health-related quality of life and better life participation.

Novel approach to unpleasant symptom clusters surrounding pruritus in patients with chronic kidney disease and on dialysis therapy

PURPOSE OF REVIEW

Chronic kidney disease-associated-pruritus (CKD-aP) is a common symptom in patients with end-stage kidney disease (ESKD) undergoing dialysis. CKD-aP typically occurs alongside other debilitating symptoms and may comprise so-called 'symptom clusters' which have synergistic effects that adversely impact patient health-related quality of life (HRQoL). Importantly, symptoms in a cluster may share a common biological mechanism. Here we review the clinical impact of CKD-aP and its association with other symptoms reported by dialysis patients. The clinical benefits of treating pruritus and its potential impact on other symptoms are also addressed.

RECENT FINDINGS

Studies have shown CKD-aP significantly impairs HRQoL in patients with ESKD undergoing dialysis and is associated with adverse clinical outcomes, including increased risk of infections, hospitalizations, and mortality. Despite these negative effects, CKD-aP remains underrecognized and undertreated in clinical practice. CKD-aP is frequently associated with other symptoms, including disturbed sleep/poor sleep quality, anxiety, depression, and pain. Clinical studies of antipruritic therapies show that reduction of itch intensity may also alleviate other associated symptoms, such as poor sleep quality.

SUMMARY

CKD-aP and its associated symptoms are inadequately managed in clinical practice. Greater understanding and awareness of CKD-aP and its surrounding symptom clusters in dialysis patients may improve their overall symptom management and HRQoL.