Clinical interpretation of the Uremic Pruritus in Dialysis Patients (UP-Dial) scale: a novel instrument for the assessment of uremic pruritus.

BACKGROUND: The Uremic Pruritus in Dialysis Patients (UP-Dial) scale is valid and reliable for uremic pruritus (UP) assessment. However, it remains unknown how the scores should be interpreted in clinical practices. OBJECTIVES: To establish a clinical interpretation of the UP-Dial by identifying severity cut-off scores according to the disease severity and burden of pruritus. METHODS: This cross-sectional study developed a classification system for the UP-Dial scores using the patient-based anchors method. From May 2012 through January 2017, 697 dialysis patients were screened. Of these, a total of 258 met the criteria for UP and completed the UP-Dial scale and three sets of patient-assessed anchor questions: (i) global UP intensity by visual analogue scale (VAS)-UP, (ii) Dermatology Life Quality Index and (iii) global kidney disease-related quality of life. The cut-off scores were generated based on the kappa (κ) coefficient of agreement and the area under receiver operating characteristic curve (AuROC) statistics. Subgroup analyses were performed to explore associations between patient characteristics and the UP-Dial severity bands. RESULTS: The proposed scores were ≤12 (mild), 13-21 (moderate) and ≥22 (severe) with κ coefficient ranging between 0.39 and 0.46. Assigned scores were associated with all patient-based anchors. The highest association was with the VAS-UP, and AuROC was 0.80 (mild; 95% CI, 0.75-0.86), 0.66 (moderate; 0.60-0.71) and 0.83 (severe; 0.77-0.89). In subgroup analysis according to patient characteristics, we did not find any significant difference. CONCLUSIONS: The estimated UP-Dial severity band can facilitate the interpretation of UP in practice-based research settings and can be used to support treatment decisions.

Development of a multidimensional assessment tool for uraemic pruritus: Uraemic Pruritus in Dialysis Patients (UP-Dial).

BACKGROUND: Dialysis patients with uraemic pruritus (UP) have significantly impaired quality of life. To assess the therapeutic effect of UP treatments, a well-validated comprehensive and multidimensional instrument needed to be established. OBJECTIVES: To develop and validate a multidimensional scale assessing UP in patients on dialysis: the Uraemic Pruritus in Dialysis Patients (UP-Dial). METHODS: The development and validation of the UP-Dial instrument were conducted in four phases: (i) item generation, (ii) development of a pilot questionnaire, (iii) refinement of the questionnaire with patient recruitment and (iv) psychometric validation. Participants completed the UP-Dial, the visual analogue scale (VAS) of UP, the Dermatology Life Quality Index (DLQI), the Kidney Disease Quality of Life-36 (KDQOL-36), the Pittsburgh Sleep Quality Index (PSQI) and the Beck Depression Inventory (BDI) between 15 May 2012 and 30 November 2015. RESULTS: The 27-item pilot UP-Dial was generated, with 168 participants completing the pilot scale. After factor analysis was performed, the final 14-item UP-Dial encompassed three domains: signs and symptoms, psychosocial, and sleep. Face and content validity were satisfied through the item generation process and expert review. Psychometric analysis demonstrated that the UP-Dial had good convergent and discriminant validity. The UP-Dial was significantly correlated [Spearman rank coefficient, 95% confidence interval (CI)] with the VAS-UP (0·76, 0·69-0·83), DLQI (0·78, 0·71-0·85), KDQOL-36 (-0·86, -0·91 to -0·81), PSQI (0·85, 0·80-0·89) and BDI (0·70, 0·61-0·79). The UP-Dial revealed excellent internal consistency (Cronbach's α 0·90, 95% CI 0·87-0·92) and reproducibility (intraclass correlation 0·95, 95% CI 0·90-0·98). CONCLUSIONS: The UP-Dial is valid and reliable for assessing UP among patients on dialysis. Future research should focus on the cross-cultural adaptation and translation of the scale to other languages.

Potential impact of Thai Kidney Transplant program on immunosuppressive utilization: an analysis of the national transplant registry.

BACKGROUND: The Thai Kidney Transplant (TKT) program was launched in October 2008 to promote transplantation among previously disadvantaged populations, using fixed-rate provider payment. This study investigated if the introduction of this program could alter the natural practice trends of immunosuppressive drug use. METHODS: Data from the Thai Transplantation Registry were analyzed. The change in trend of immunosuppressive use was assessed using the multivariate adaptive regression splines (MARS) technique. RESULTS: During 1987-2012, 3975 kidney transplantations were done. The average age of patients was 42 years and 62% were male. Chronic glomerulonephritis accounted for one third of those with known causes of end-stage renal disease (ESRD). Eighty-six percent were on hemodialysis before transplantation. Prednisolone was used in 95.87% of all transplant recipients, whereas calcineurin inhibitors (CNIs), mycophenolates (MPAs), azathioprine (AZA), and mammalian target of rapamycin inhibitors (mTORis) were used in 95.67%, 64.22%, 12.25%, and 2.31%, respectively. Overall use after 2008 was decreased for AZA (18.16% to 3.40%) and mTORis (2.86% to 1.5%) but increased for MPAs (50.80% to 84.34%), CNIs (95.43% to 96.04%), and prednisolone (95.60% to 96.29%), as compared with before the program inception. The slopes of use trends of AZA, MPAs, and CNIs did not significantly marginally differ from their natural trends before the program inception (P = .496, .108, and .741, respectively). However, the natural increasing use trend of mTORis significantly changed to a decreasing pattern after the introduction of the TKT program (P = .018). CONCLUSION: Fixed-rate provider payment might interfere with the natural practice trends of immunosuppressive drug use.

Living donor age and kidney transplant outcomes.

We assessed the relationship between living donor (LD) age and kidney survival in 1063 adults transplanted between 1980 and 2007. Increasing LD age was associated with lower kidney function (GFR) before and after transplantation and loss of GFR beyond 1 year. Increasing LD age was also associated with low-moderate proteinuria posttransplant (151-1500 mg/day, p < 0.0001). By univariate analysis, reduced graft survival related to lower GFR at 1 year [HR = 0.925 (0.906-0.944), p < 0.0001], proteinuria [HR = 1.481 (1.333-1.646), p < 0.0001] and increasing LD age [HR = 1.271 (1.219-1.326), p = 0.001]. The impact of LD age on graft survival was noted particularly >4 years posttransplant and was modified by recipient age. Thus, compared to a kidney graft that was within 5 years of the recipient age, younger kidneys had a survival advantage [HR = 0.600 (0.380-0.949), p = 0.029] while older kidneys had a survival disadvantage [HR = 2.217 (1.507-3.261), p < 0.0001]. However, this effect was seen only in recipients <50 years old. By multivariate analysis, the relationship between LD age and graft survival was independent of GFR but related to proteinuria. In conclusion, LD age is an important determinant of long-term graft survival, particularly in younger recipients. Older kidneys with reduced survival are identifiable by the development of proteinuria posttransplant.