Laboratory and dialysis characteristics in hemodialysis patients suffering from chronic itch - results from a representative cross-sectional study

BACKGROUND A representative cross-sectional study showed that chronic itch (lasting for a minimum of 6 weeks) affects 25.2 % (point prevalence) of hemodialysis (HD) patients. Pathophysiology and etiology of chronic itch (CI) in HD are still unclear. METHODS We investigated 860 HD patients from a representative randomly selected cluster-sample considering the regional distributions of dialysis units in Germany. The current analyses report comorbidities, laboratory values and dialysis characteristics of HD patients in relation to CI. RESULTS Diabetes was the only comorbidity that was associated with the occurrence of itch but interestingly with less CI. Except for creatinine, phosphorus, and parathormone, there were no significant associations between the occurrence and characteristics of CI and any laboratory value. Kt/V was not associated with the presence of CI. Patients dialyzed with polyarylethersulfone-membrane showed significantly more CI in all prevalence estimates and those dialyzed with polysulfone-membrane were significantly less affected by CI. CONCLUSIONS Long-term follow-up studies will show if the type of dialysis membrane influences the development of CI in HD patients. It is most likely that several factors e.g. elevated parathormone, origin of end stage renal disease (ESRD), type of dialysis membrane, and a neuropathic component all contribute to the occurrence of CI in HD patients. Future research should consider a multifactorial origin of itch in HD.