Comparisons of leptin, incretins and body composition in obese and lean patients with hypopituitarism and healthy individuals.
OBJECTIVE
To identify possible abnormalities specific for obesity in hypopituitary patients.


METHODS
Cross-sectional case-control study. MEASUREMENTS AND STUDY SUBJECTS: Body composition (DEXA) and measurements of fasting plasma levels of glucose-dependent insulinotropic polypeptide (GIP), glucagon-like peptides (GLPs), insulin, C-peptide, glucose, leptin and lipids were performed in 25 hypopituitary patients (15 obese, 10 normal weight) and 26 BMI and age-matched healthy controls (16 obese, 10 normal weight). All hypopituitary patients had GH deficiency and received adequate substitution therapy on this and other deficient axes (3 +/- 1).


RESULTS
Fasting GIP-levels were significantly higher in obese hypopituitary patients compared to lean hypopituitary patients (P < 0.01), while the fasting concentrations of GLP-1 and GLP-2 were comparable between obese and lean hypopituitary patients. The same trend was seen in obese healthy controls vs. lean controls. No differences were observed in glucose, insulin or C-peptide between the hypopituitary patients and the controls. Leptin levels were increased in obese hypopituitary patients compared to lean hypopituitary patients when adjusted for gender. At least a 2-fold higher level of leptin was observed in women compared to men in both patient groups and healthy controls. Lean female hypopituitary patients had higher leptin levels than matched controls.


CONCLUSIONS
Fasting levels of GIP were elevated in obese substituted hypopituitary patients, while fasting concentrations of GLPs were similar. Obese hypopituitary patients had the same degree of hyperinsulinaemia, affected glucose tolerance, dyslipoproteinaemia and central obesity as obese healthy controls. Further studies are required to identify the possible biochemical reasons for obesity in patients with apparently well-substituted hypopituitarism.
Mersebach
H
H
Department of Endocrinology, Rigshospitalet, Copenhagen University Hospital, Denmark. mersebach@rh.dk
Svendsen
O L
OL
Holst
J J
JJ
Astrup
A
A
Feldt-Rasmussen
U
U
D000328:Adult; D000886:Anthropometry; D001823:Body Composition; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D005215:Fasting / Q000097:blood; D005260:Female; D005749:Gastric Inhibitory Polypeptide / Q000097:blood; D005934:Glucagon; D052216:Glucagon-Like Peptide 1; D053767:Glucagon-Like Peptide 2; D004763:Glucagon-Like Peptides; D019382:Human Growth Hormone / Q000627:therapeutic use; D006801:Humans; D007018:Hypopituitarism / Q000097:blood* / Q000150:complications / Q000188:drug therapy; D020738:Leptin / Q000097:blood*; D008055:Lipids / Q000097:blood; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000097:blood* / Q000209:etiology; D010446:Peptide Fragments / Q000097:blood*; D010455:Peptides / Q000097:blood; D013851:Thinness / Q000097:blood
D053767:Glucagon-Like Peptide 2; D020738:Leptin; D008055:Lipids; D010446:Peptide Fragments; D010455:Peptides; C055453:glucagon-like peptide 1 (7-36)amide; D019382:Human Growth Hormone; D005749:Gastric Inhibitory Polypeptide; D004763:Glucagon-Like Peptides; D052216:Glucagon-Like Peptide 1; D005934:Glucagon