The factors that are associated with itching in chronic kidney patients and evaluation of itching with the 5d itch scale

Abstract

Objective: Uremic pruritus is a distressing complication of chronic kidney disease (CKD), associated with mortality, and negatively impacts quality of life. The 5D-Itch Scale (5D-IS) is an easy-to-apply technique that evaluates 5 different dimensions of itching such as duration, severity, course, disability, and prevalence. We aimed to investigate the prevalence of itching in different CKD stages using the 5D-IS and to investigate the factors associated with itching in CKD patients.

Materials and methods: 5D-IS was used to evaluate itching in chronic hemodialysis (HD) and Stage 3-5 CKD patients. Total itching score and sub-scores consist of duration, severity, course, disability and distribution were obtained. Itching scores and prevalence according to CKD stages were investigated. Also the relationships between itching scores and some laboratory and clinical parameters such as iPTH, Ca, P, CRP levels were examined.

Results: 158 CKD patients included in the study included (110 Stage 3-5 and 48 HD). The frequency of itching was higher in HD patients than in predialysis patients (62.5% vs 46.4%; p = 0.04). The total itching score increased along with CKD stages 3 to 5 (7.75 ± 3.39, 7.82 ± 4.11 and 9.08 ± 5.12 respectively; p = 0.14). The severity, duration and course scores of itching were similar between the groups, but the distribution scores increased as the CKD stage increased. The laboratory and clinical characteristics of patients with and without itching were not different. Even if a significant positive correlation was detected between the parathyroid hormone levels and both the total 5D-IS scores and all of the sub-scores, Ca and P values were not correlated with itching scores. In the multiple regression analysis, the only parameter that had an effect on the total 5D-IS Score was the parathyroid hormone level.

Conclusion: In CKD, itching affects 40-70% of patients from the early stages. As the CKD stage increases, itching spreads throughout the body. The only parameter that seems to be associated with itching is the PTH level.

Keywords: 5D Itch scale; End-Stage renal disease; Hemodialysis; Uremic pruritus.