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

Abstract

Rationale & objective: 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.

Study design: Observational study.

Setting & participants: All patients receiving maintenance dialysis in Stockholm, Sweden, during 2005-2021.

Exposure: Clinically recognized pruritus, defined using ICD-10 codes or the prescription for anti-pruritus treatments (including UV-therapy).

Outcomes: 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.

Analytical approach: 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.

Results: 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.

Limitations: 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.

Conclusion: At least one-third of patients experience pruritus during their first years on dialysis, and pruritus was consistently associated with adverse health outcomes.