Symptom Cluster Science in Chronic Kidney Disease: A Literature Review.

The purpose of this review was to synthesize evidence on symptom clusters in patients with chronic kidney disease (CKD). The quality of studies was evaluated using the Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. Twelve articles met inclusion criteria. Patients had CKD ranging from Stages 2 through 5. Most studies determined clusters using variable-centered approaches based on symptoms; however, one used a person-centered approach based on demographic and clinical characteristics. The number of clusters identified ranged from two to five. Several clusters were prominent across studies including symptom dimensions of fatigue/energy/sleep, neuromuscular/pain, gastrointestinal, skin, and uremia; however, individual symptoms assigned to clusters varied widely. Several clusters correlated with patient outcomes, including health-related quality of life and mortality. Identifying symptom clusters in CKD is a nascent field, and more research is needed on symptom measures and statistical methods for clustering. The clinical implications of symptom clusters remain unclear.