Evaluation of uraemic pruritus in long-term dialysis patients using a modified Chinese scale

To examine the reliability and validity of a modified Chinese version of the uraemic pruritus scale for measurement of different degrees of itching, as well as to identify the predictors for the severity of uraemic pruritus among long-term dialysis patients.

Long-term dialysis patients (n = 110) were recruited for a cross-sectional study from a medical centre in Taiwan. A modified Chinese version of the uraemic pruritus scale was used to evaluate sleep disturbance and the severity, frequency and distribution of itching. Reliability was evaluated using item-total correlations, Cronbach's α, and intra-class correlation. Validity was evaluated by the content validity index, predictive and discriminative validity. Multiple linear regression was used on the predictors for the severity of uraemic pruritus.

After optimization for reliability, the scale retained seven items. The Cronbach's α was 0.86, and the results showed that the scale had predictive and discriminative validity. High intact-parathyroid hormone and creatinine clearance rate were important predictors for the severity of uraemic pruritus. The severity of uraemic pruritus was the important predictor for the sleeping disturbance.

The modified uraemic pruritus scale can discriminate between patients with a total pruritus score of ≥11 and those with a score of 0 points. The modified Chinese scale is a useful tool for clinically assessing the various degrees of itching among long-term dialysis patients. Our study validates that it could apply to clinical practice in assessment of uraemic pruritus.