Burden of CKD-Associated Pruritus and Adverse Clinical Outcomes in Patients Receiving Dialysis: The Stockholm CREAtinine Measurements (SCREAM) Project

Abstract

Pruritus is a common but not well-characterized complaint of patients receiving maintenance dialysis. This study sought to quantify the burden of pruritus and its associated adverse health outcomes in this population. Observational study. All patients receiving maintenance dialysis in Stockholm, Sweden, during 2005-2021. Clinically recognized pruritus, defined using ICD-10 codes or the prescription for anti-pruritus treatments (including UV-therapy). All-cause mortality, severe infection-related hospitalizations (composite of endocarditis, peritoneal dialysis-related peritonitis, hemodialysis/peritoneal dialysis-related catheter infection, sepsis due to Staphylococcus Spp., or skin infection) and incident diagnoses of anxiety/depression and sleep disorders. Multivariable logistic regression and cause-specific hazards models to analyze factors associated with prevalent and new-onset pruritus, respectively. Multivariable cause-specific hazards models with time-varying exposure to explore the association of prevalent and new-onset pruritus with adverse health outcomes. Among 3281 dialysis patients (median age 64 years, 66% men, 69% on hemodialysis,77% incident dialysis patients), 456 (14%) had pruritus at enrollment. During a median follow-up of 3.3 [IQR: 1.3-9.2] years, 539 (19%) additional patients developed pruritus. Older age, female sex, a lower serum albumin level, and higher C-reactive protein, serum calcium and phosphorus levels were independently associated with pruritus. Compared to patients without pruritus, patients with pruritus were at a higher risk of suffering sleep disorders (adjusted HR: 1.96 [95%CI 1.60-2.39]), developing anxiety/depression (aHR: 1.56 [1.23-1.98]), and being hospitalized for severe infections (aHR: 1.36 [1.18-1.57]), the latter attributed to higher risk of sepsis and peritoneal dialysis-related peritonitis. There was no detectable association between developing pruritus and all-cause mortality. Potential misclassification bias if pruritus is not clinically recognized; lack of information on pruritus intensity/severity; use of diagnostic codes for exposure and outcome diagnoses. At least one-third of patients experience pruritus during their first years on dialysis, and pruritus was consistently associated with adverse health outcomes.