title: Age dependency of regional impedance indices regardless of clinical stage in patients with cirrhosis of the liver.
abstract: OBJECTIVE
  To prospectively assess if ageing itself induces modifications of the impedance indices (resistance and pulsatility indexes) of hepatic, splenic, superior mesenteric and renal arteries in patients with liver cirrhosis.
  
  
  METHODS
  78 consecutive patients with cirrhosis (41 males, 37 females, Child-Pugh score 7 [range 5 - 12]) were studied by colour-Doppler ultrasound. The resistance index (RI) and pulsatility index (PI) were determined in the main hepatic artery, intraparenchymal branches of hepatic, splenic, and renal arteries, and superior mesenteric artery; clinical data were simultaneously collected. Logistic regression analysis was performed to assess the relative impact of age, severity of liver disease and other relevant variables on the increase of impedance indices. Linear regression analysis was used to identify a coefficient to adjust RIs and PIs to age.
  
  
  RESULTS
  Resistance and pulsatility indices of all the vessels studied except of the superior mesenteric artery showed a direct correlation with age (e. g. splenic artery RI: R = 0.520, p < 0.0001), and correlated most strongly with Child-Pugh score (e. g. right renal artery PI: R = 0.462, p < 0.0001). Age was associated independently with increased PI and RI in hepatic, splenic and renal arterial districts. In these vessels, the RI threshold of normality can be adjusted to the decade of age adding a correction of 0.03.
  
  
  CONCLUSIONS
  Ageing itself induces an increase of hepatic, splenic and renal impedance indices in cirrhotic patients. The threshold of normality for these indices in cirrhosis should be adjusted according to the patients' age.
authors.affiliation: Dip. Medicina Interna, Cardioangiologia, Epatologia, University of Bologna, Italy. aberzigo@clinic.ub.es
authors.forename: A
authors.initials: A
authors.lastname: Berzigotti
authors.forename: N
authors.initials: N
authors.lastname: Castaldini
authors.forename: V
authors.initials: V
authors.lastname: Rossi
authors.forename: D
authors.initials: D
authors.lastname: Magalotti
authors.forename: C
authors.initials: C
authors.lastname: Tiani
authors.forename: P
authors.initials: P
authors.lastname: Zappoli
authors.forename: M
authors.initials: M
authors.lastname: Zoli
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006499:Hepatic Artery / Q000000981:diagnostic imaging*; D006801:Humans; D008103:Liver Cirrhosis / Q000145:classification / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D008111:Liver Function Tests; D008297:Male; D017538:Mesenteric Artery, Superior / Q000000981:diagnostic imaging*; D008875:Middle Aged; D011673:Pulsatile Flow / Q000502:physiology*; D012016:Reference Values; D012077:Renal Artery / Q000000981:diagnostic imaging*; D013157:Splenic Artery / Q000000981:diagnostic imaging*; D013223:Statistics as Topic; D018615:Ultrasonography, Doppler, Color; D014655:Vascular Resistance / Q000502:physiology*