title: Impaired postprandial response of the insulin-like growth factor system in maintenance haemodialysis.
abstract: OBJECTIVE
  Patients on maintenance haemodialysis (HD) have reduced circulating free and bioactive insulin-like growth factor I (IGF-I) due to increased IGF-binding proteins (IGFBPs). This study investigated the postprandial response of the IGF system in HD patients compared with matched healthy subjects.
  
  
  METHODS
  In a crossover study, twelve nondiabetic HD patients were assigned in a random order to three 10-h study days: (1) a non-HD day with one meal served at baseline (NHDM1), (2) an HD day with one meal served during HD (HDM1) and (3) an HD day with two meals served during and after HD, respectively (HDM2). Twelve healthy controls conducted session 1.
  
  
  RESULTS
  After the baseline meal, insulin concentrations changed similarly in HD patients and controls, whereas hyperglycaemia was more prolonged in HD patients (P < 0·001). Postprandial IGFBP-1 showed greater reductions from baseline in controls (-76% [-81; -70%], mean [95% confidence intervals], P < 0·001) than in patients on non-HD days (-45% [-57; -30%], P < 0·001). In the latter group, the response was even more attenuated during HD (-22% [-38; -1%] and -24% [-40; -4%], P ≤ 0·041). After the second meal on HDM2 days, IGFBP-1 further decreased (-50% [-61; -37%], P < 0·001), whereas IGFBP-1 returned to baseline levels on the other study days. Consistently, at the end of the study days, bioactive IGF-I was significantly above baseline only on HDM2 days (+22% [+5; +43%], P = 0·012).
  
  
  CONCLUSIONS
  HD patients were unable to suppress IGFBP-1 to the same extent as healthy controls, which may increase the risk of protein-energy wasting in maintenance HD. A second meal after HD, however, effectively suppressed IGFBP-1 and increased bioactive IGF-I.
authors.affiliation: Department of Renal Medicine, Aarhus University Hospital, Aarhus C, Denmark; Department of Clinical Medicine, Faculty of Health, Aarhus University, Aarhus C, Denmark.
authors.forename: Mark
authors.initials: M
authors.lastname: Reinhard
authors.forename: Jan
authors.initials: J
authors.lastname: Frystyk
authors.forename: Bente
authors.initials: B
authors.lastname: Jespersen
authors.forename: Else
authors.initials: E
authors.lastname: Randers
authors.forename: Mette
authors.initials: M
authors.lastname: Bjerre
authors.forename: Jens S
authors.initials: JS
authors.lastname: Christiansen
authors.forename: Allan
authors.initials: A
authors.lastname: Flyvbjerg
authors.forename: Bo M
authors.initials: BM
authors.lastname: Bibby
authors.forename: Per
authors.initials: P
authors.lastname: Ivarsen
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000378:metabolism; D001786:Blood Glucose / Q000032:analysis; D016022:Case-Control Studies; D018592:Cross-Over Studies; D005260:Female; D006801:Humans; D007328:Insulin / Q000097:blood; D018970:Insulin-Like Growth Factor Binding Protein 1 / Q000378:metabolism; D018969:Insulin-Like Growth Factor Binding Proteins / Q000378:metabolism*; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D019518:Postprandial Period; D011897:Random Allocation; D006435:Renal Dialysis / Q000379:methods*
chemical_list: D015415:Biomarkers; D001786:Blood Glucose; D007328:Insulin; D018970:Insulin-Like Growth Factor Binding Protein 1; D018969:Insulin-Like Growth Factor Binding Proteins; D007334:Insulin-Like Growth Factor I