#1999 Retrospective observational study of uremic pruritus prevalence on dialysis

Abstract

Abstract Background and Aims In Spain, the prevalence of moderate-severe Uremic Pruritus (UP) was 46% and 40% in the DOPPS I and DOPPS. This symptom is usually underdiagnosed and could worsen the quality of life, as some recent studies have revealed. The last reports regarding UP prevalence date back to 2004, hence we decided to assess its current frequency of this while exploring the degree of recognition along with other UP-associated factors. Method This study includes 192 patients in renal replacement therapy (RRT), retrospectively recruited from our centre. Data were collected from revisit medical records in 2021. UP was evaluated using a visual analogic scale (VAS). In addition, age, time on dialysis, UP treatment, haemoglobin, eosinophils, plasma levels of calcium, phosphorus, urea, parathyroid hormone, c-reactive protein (CRP), and clearance (measured by KT/V) were also recorded. Results Average patient age was 61.3 years old, with an average time in dialysis of 37.4 months. The most common group of chronic kidney disease was glomerular diseases (25.5%). The patient distribution by RRT was: 51.9% in haemodialysis (HD), 36.5% in peritoneal dialysis (PD), and 11.6% in home haemodialysis (HHD). UP average prevalence was 56.7% (50% in HHD, 55.2% in HD and 60.9% in PD), of which 69.8% had a VAS ≥ 5. UP was statistically associated with older age (p = 0.017) and higher plasmatic phosphorus (p = 0.015). Notably, only 51.9% UP patients had been prescribed specific drugs for itching. Among UP treated patients, 70.9% improved 3 or more VAS points (with no differences among drugs). Interestingly, this improvement was associated with lower calcium levels (p < 0.0001), the absence of peripheral artery disease (PAD) (p = 0.035), and the shortest time on dialysis (p = 0.001). Conclusion Despite the advances made in HD techniques and the recent incorporation of biocompatible solutions in PD, UP remains a frequent symptom among dialysis patients, without relevant prevalence improvements over the last 20 years. UP was misdiagnosed and mistreated in our unit, since just 51.9% of patients with UP were under treatment. In addition, clinical response to treatment was appropriate in 70.9% of patients, and our results suggest that calcium, PAD, and time on dialysis could predict the response to the treatment. Therefore, our study supports previous data, highlighting UP as a frequent underdiagnosed symptom among dialysis patients; and opens the path for new research in the identification of novel prognosis markers.