title: Preliminary observations on the association between serum IL-6 and hydration status and cardiovascular risk in patients treated with peritoneal dialysis.
abstract: Systemic inflammation, as defined by elevated blood IL-6, is a strong independent predictor of peritoneal dialysis (PD) patient survival. The present study has aimed to determine whether there exists a particular "phenotype" associated with high systemic IL-6 that characterizes PD patients in terms of their fluid status and cardiac parameters.
  
  
  
  Fifty-seven prevalent PD patients were classified according to serum concentrations of IL-6. The degree of overhydration was assessed by bioimpedance analysis (BIA). Echocardiography and serum concentrations of NT-proBNP and troponin T were used to assess cardiovascular risk.
  
  
  
  Patients with high serum IL-6 were older, more often diabetic, treated with PD for longer, and significantly more overhydrated. There was a significant correlation between serum IL-6, hydration status (r=0.38; p=0.002) and serum albumin (r=-0.35; p=0.009). Multivariate regression analysis confirmed a strong association of overhydration, hypoalbuminemia, and systemic IL-6 concentration. Patients with high IL-6 had significantly increased levels of both NT-proBNP (r=0.36; p=0.006) and TnT (r=0.50; p<0.001) in the absence of abnormalities in echocardiography.
  
  
  
  High systemic IL-6 identifies PD patients with increased cardiovascular risk that is significantly related to overhydration. Thus, the measurement of serum IL-6 may contribute to the more accurate assessment of cardiovascular status in patients undergoing PD.
authors.affiliation: Department of Pathophysiology, Poznan University of Medical Sciences, Poland; Department of Nephrology, Transplantology and Internal Medicine, Poznan University of Medical Sciences, Poland.
authors.forename: Dorota
authors.initials: D
authors.lastname: Sikorska
authors.affiliation: Department of Nephrology, Transplantology and Internal Medicine, Poznan University of Medical Sciences, Poland.
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Pawlaczyk
authors.affiliation: Department of Pathophysiology, Poznan University of Medical Sciences, Poland.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Roszak
authors.affiliation: Department of Pathophysiology, Poznan University of Medical Sciences, Poland.
authors.forename: Natasza
authors.initials: N
authors.lastname: Czepulis
authors.affiliation: Department of Nephrology, Transplantology and Internal Medicine, Poznan University of Medical Sciences, Poland.
authors.forename: Andrzej
authors.initials: A
authors.lastname: Oko
authors.affiliation: Department of Transplantology, General, Vascular and Plastic Surgery, Poznan University of Medical Sciences, Poland.
authors.forename: Marek
authors.initials: M
authors.lastname: Karczewski
authors.affiliation: Department of Pathophysiology, Poznan University of Medical Sciences, Poland.
authors.forename: Andrzej
authors.initials: A
authors.lastname: Breborowicz
authors.affiliation: Department of Pathophysiology, Poznan University of Medical Sciences, Poland. Electronic address: jwitow@ump.edu.pl.
authors.forename: Janusz
authors.initials: J
authors.lastname: Witowski
mesh_terms: D000328:Adult; D000368:Aged; D002318:Cardiovascular Diseases / Q000097:blood* / Q000209:etiology* / Q000378:metabolism; D004452:Echocardiography / Q000379:methods; D017097:Electric Impedance; D005260:Female; D006801:Humans; D015850:Interleukin-6 / Q000097:blood*; D008297:Male; D008875:Middle Aged; D000074267:Organism Hydration Status / Q000502:physiology*; D010530:Peritoneal Dialysis / Q000379:methods; D012307:Risk Factors; D012709:Serum Albumin / Q000378:metabolism; D014883:Water-Electrolyte Imbalance / Q000097:blood / Q000378:metabolism
chemical_list: C508600:IL6 protein, human; D015850:Interleukin-6; D012709:Serum Albumin
keywords: Cardiovascular risk; IL-6; Overhydration