Date Published: August 6, 2013
Publisher: Public Library of Science
Author(s): Mei-Ju Ko, Hon-Yen Wu, Hung-Yuan Chen, Yen-Ling Chiu, Shih-Ping Hsu, Mei-Fen Pai, Chun-Fu Lai, Hui-Min Lu, Shu-Chen Huang, Shao-Yu Yang, Su-Yin Wen, Hsien-Ching Chiu, Fu-Chang Hu, Yu-Sen Peng, Shiou-Hwa Jee, Rosa Maria Affonso Moysés.
Uremic pruritus is a common and intractable symptom in patients on chronic hemodialysis, but factors associated with the severity of pruritus remain unclear. This study aimed to explore the associations of metabolic factors and dialysis adequacy with the aggravation of pruritus.
We conducted a 5-year prospective cohort study on patients with maintenance hemodialysis. A visual analogue scale (VAS) was used to assess the intensity of pruritus. Patient demographic and clinical characteristics, laboratory parameters, dialysis adequacy (assessed by Kt/V), and pruritus intensity were recorded at baseline and follow-up. Change score analysis of the difference score of VAS between baseline and follow-up was performed using multiple linear regression models. The optimal threshold of Kt/V, which is associated with the aggravation of uremic pruritus, was determined by generalized additive models and receiver operating characteristic analysis.
A total of 111 patients completed the study. Linear regression analysis showed that lower Kt/V and use of low-flux dialyzer were significantly associated with the aggravation of pruritus after adjusting for the baseline pruritus intensity and a variety of confounding factors. The optimal threshold value of Kt/V for pruritus was 1.5 suggested by both generalized additive models and receiver operating characteristic analysis.
Hemodialysis with the target of Kt/V ≥1.5 and use of high-flux dialyzer may reduce the intensity of pruritus in patients on chronic hemodialysis. Further clinical trials are required to determine the optimal dialysis dose and regimen for uremic pruritus.
Uremic pruritus is a common and intractable symptom in patients on chronic hemodialysis , . It causes serious discomfort and skin damage, negatively affects the quality of life, and may be associated with sleep disturbance, inflammation, and higher mortality , . The pathophysiology of uremic pruritus is complex. Previous studies have shown that xerosis, divalent ions, calcium-phosphate product, C-reactive protein, hepatitis, hyperparathyroidism, immune derangement, and opioid system alternation may be associated with uremic pruritus –. However, there has not been a consensus reached among those studies, and uremic pruritus remains poorly characterized. Because of insufficient understanding for uremic pruritus, current therapeutic options for uremic pruritus are limited and unsatisfactory , .
This is the first prospective cohort study to investigate clinical parameters and metabolic profiles for uremic pruritus in hemodialysis patients using repeatedly measured data. In the study, we have demonstrated that the aggravation of pruritus was associated with lower Kt/V after adjusting for a variety of confounding factors. We’ve also shown that the patients with baseline Kt/V below 1.5 suffered from aggravation of pruritus intensity.