Pruritus in haemodialysis patients: International results from the Dialysis Outcomes and Practice Patterns Study (DOPPS).

BACKGROUND Pruritus affects many haemodialysis (HD) patients. In this study, pruritus and its relationship to morbidity, mortality, quality of life (QoL), sleep quality and patient laboratory measures were analysed in >300 dialysis units in 12 countries. METHODS Pruritus data were collected from 18 801 HD patients in the Dialysis Outcomes and Practice Patterns Study (DOPPS) (1996-2004). Analyses were adjusted for age, gender, black race, Kt/V, haemoglobin, serum albumin, albumin-corrected serum calcium, serum phosphorus, 13 comorbidities, depression, years on dialysis, country and facility clustering effects. RESULTS Moderate to extreme pruritus was experienced by 42% of prevalent HD patients in DOPPS during 2002/2003. Many patient characteristics were significantly associated with pruritus, but this did not explain the large differences in pruritus between countries (ranging from 36% in France to 50% in the UK) and between facilities (5-75%). Pruritus was slightly less common in patients starting HD than in patients on dialysis >3 months. Pruritus in new end-stage renal disease (ESRD) patients likely results from pre-existing conditions and not haemodialysis per se, indicating the need to understand development of pruritus before ESRD. Patients with moderate to extreme pruritus were more likely to feel drained [adjusted odds ratio (AOR) = 2.3-5.2, P < 0.0001] and to have poor sleep quality (AOR = 1.9-4.1, P < or = 0.0002), physician-diagnosed depression (AOR = 1.3-1.7, P < or = 0.004), and QoL mental and physical composite scores 3.1-8.6 points lower (P < 0.0001) than patients with no/mild pruritus. Pruritus in HD patients was associated with a 17% higher mortality risk (P < 0.0001), which was no longer significant after adjusting for sleep quality measures. CONCLUSIONS The pruritus/mortality relationship may be substantially attributed to poor sleep quality. The many poor outcomes associated with pruritus underscore the need for better therapeutic agents to provide relief for the 40-50% of HD patients affected by pruritus.