Prognostic importance and determinants of uremic pruritus in patients receiving peritoneal dialysis: A prospective cohort study

Abstract

Background: Uremic pruritus is a common and frustrating symptom among patients receiving peritoneal dialysis (PD). This study aimed to examine the prognostic importance of uremic pruritus and to identify the determinants for higher pruritus intensity in PD patients.

Methods: We conducted a prospective cohort study of patients receiving maintenance PD. A visual analogue scale (VAS) score was used to measure the intensity of uremic pruritus. The composite endpoint of PD technique failure or all-cause death was assessed using a multivariable Cox proportional hazards model. The determinants for the VAS score of uremic pruritus was assessed using a multivariable linear regression model.

Results: Among the 85 PD patients, 24 (28%) had uremic pruritus. During a median follow-up of 28.0 months, 12 patients experienced technique failure, and 7 died. We found that a higher VAS score of pruritus intensity was an independent risk factor for technique failure or death (hazard ratio, 1.64; 95% confidence interval, 1.18 to 2.28; P = 0.003) after adjusting for a variety of confounding factors. We also found that a weekly total Kt/V of less than 1.88, a longer duration of dialysis, a higher dietary protein intake, and higher blood levels of intact parathyroid hormone and high-sensitivity C-reactive protein were independent determinants of higher VAS scores of pruritus intensity.

Conclusions: Our results show that uremic pruritus is an independent risk factor of technique failure and death in patients receiving PD. We also found that a weekly total Kt/V < 1.88 is associated with higher intensity of uremic pruritus in PD patients.

Fig 1. Histogram and density plot of visual analogue scale score of pruritus intensity in the study population (n = 85).

The density of vertical axis represents the percentage of study participants.

Fig 2. The generalized additive model plot of the relationship between weekly total Kt/V and the visual analogue scale (VAS) score of pruritus intensity.

The model of the plot is adjusted for duration of dialysis, normalized protein nitrogen appearance, age, high-sensitivity C-reactive protein, total cholesterol, and intact parathyroid hormone. The little vertical bars on the horizontal axis display the distribution of individual observations. The plot indicates that a weekly total Kt/V < 1.88 is associated with the aggravation of pruritus intensity.