Chronic Pruritus in Predialysis Chronic Kidney Disease: Prevalence, Phenotype and Temporal Patterns in a Prospective...

CKD-associated pruritus (CKD-aP) is a burden some symptom with incompletely understood pathophysiology and limited predialysis data. In this prospective observational study, 95 adult nondialysis CKD patients (stages G1-G5) were followed for up to 36 months (232 observations), 86 patients were analysed after exclusion of chronic dermatological conditions. Chronic pruritus (≥6 weeks) was assessed using a numerical rating scale (NRS) and anatomical mapping. Chronic pruritus occurred in 26 of 86 patients (30.2%), with numerically higher prevalence in advanced CKD (G3b-5 : 32.8% vs G1-3a: 22.7%), whereas intensity was numerically higher in early CKD (median 8 vs 5). The back, legs and head/ face were most frequently affected, consistent with the bilateral, nondermatomal pattern described in dialysis populations. Among patients with repeated assessments, 19.0% showed an episodic trajectory and 7.6% had persistent pruritus. Multivariable logistic regression and generalized estimating equations (GEE) were used to identify independent predictors of chronic pruritus. No laboratory parameter, including PTH, was independently associated with pruritus. Dyslipidaemia was the only clinical characteristic significantly associated with pruritus status (69.2% vs 43.3%, p=0.035). Given the modest sample size, smaller effect estimates may have been missed. CKD-aP affects approximately 1 in 3 predialysis patients, follows an episodic course, and is not explained by any single biochemical marker, supporting multifactorial pathophysiology.