Elevated bound leptin correlates with energy expenditure in cirrhotics.
OBJECTIVE
Leptin, found to be elevated in patients with liver cirrhosis, may contribute to the inadequate energy expenditure and malnutrition associated with a negative prognosis for these patients. Our aim was to characterize leptin components and their relationships to body composition, resting energy expenditure (REE), and substrate use in patients with posthepatic liver cirrhosis.


METHODS
Using specific radioimmunoassays, we measured free leptin and bound leptin in 27 cirrhotics and 27 matched control subjects. In the cirrhotic group, body composition and REE were determined.


RESULTS
Free leptin was not different in cirrhotics and control subjects and was related to body mass index (controls: r = 0.34, P < 0.05; cirrhotics: r = 0.55, P < 0.005) and to fat mass (cirrhotics: r = 0.76, P < 0.0001). Bound leptin was significantly higher in cirrhotic subjects than in controls (P < 0.001) and was related to REE x fat-free mass(-1) (r = 0.57, P < 0.005) or to the difference between measured and estimated REE (r = 0.55, P < 0.005).


CONCLUSIONS
Free leptin reflects fat mass in controls and cirrhotics. Increased serum leptin in cirrhotics is a result of increased bound leptin serum concentrations, which are positively related to energy expenditure. Moreover, bound leptin may be a useful marker for inadequate energy expenditure in patients with liver cirrhosis.
Ockenga
J
J
Department of Gastroenterology and Hepatology, Hannover Medical School, Hannover, Germany. Ockenga.Johann@mh-hannover.de
Bischoff
S C
SC
Tillmann
H L
HL
Rifai
K
K
Widjaja
A
A
Böker
K H
KH
Manns
M P
MP
Brabant
G
G
D000273:Adipose Tissue / Q000473:pathology; D001823:Body Composition; D015992:Body Mass Index; D004734:Energy Metabolism / Q000502:physiology*; D005260:Female; D006801:Humans; D020738:Leptin / Q000097:blood / Q000378:metabolism*; D008103:Liver Cirrhosis / Q000097:blood* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D012146:Rest
D020738:Leptin