title: Phenotyping of type 2 diabetes mellitus at onset on the basis of fasting incretin tone: Results of a two-step cluster analysis.
abstract: OBJECTIVE
  According to some authors, in type 2 diabetes there is a reduced postprandial action of glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP). However, little is known about the role of fasting incretins in glucose homeostasis. Our aim was to evaluate, through a two-step cluster analysis, the possibility of phenotyping patients with type 2 diabetes at onset on the basis of fasting GLP-1, GIP and ghrelin.
  
  
  METHODS
  A total of 96 patients with type 2 diabetes within 6 months of onset (mean age 62.40 ± 6.36 years) were cross-sectionally studied. Clinical, anthropometric and metabolic parameters were evaluated. At fasting the following were carried out: assay of GLP-1, GIP, ghrelin, insulin, C-peptide, glucagon and a panel of adipocytokines (visfatin, resistin, leptin, soluble leptin receptor and adiponectin).
  
  
  RESULTS
  The analysis resulted in two clusters: cluster 1 (63 patients) had significantly lower levels of GLP-1 (4.93 ± 0.98 vs 7.81 ± 1.98 pmol/L; P < 0.001), GIP (12.73 ± 9.44 vs 23.88 ± 28.56 pmol/L; P < 0.001) and ghrelin (26.54 ± 2.94 vs 39.47 ± 9.84 pmol/L; P < 0.001) compared with cluster 2 (33 patients). Between the two clusters, no differences in age, duration of disease, sex, clinical-anthropometric parameters, insulin sensitivity and adipocytokines were highlighted. However, cluster 1 was associated with significantly higher levels of glycated hemoglobin (7.4 ± 0.61 vs 6.68 ± 0.57%, P = 0.007), glucagon (232.02 ± 37.27 vs 183.33 ± 97.29 ng/L; P = 0.001), fasting glucose (7.85 ± 1.60 vs 6.93 ± 1.01 mmol/L; P = 0.003) and significantly lower levels of C-peptide (0.12 ± 0.11 vs 0.20 ± 0.20 nmol/L; P = 0.017).
  
  
  CONCLUSIONS
  The present study suggests that fasting incretins play an important role in the pathophysiology of type 2 diabetes, which requires to further investigation.
authors.affiliation: Biomedical Department of Internal and Specialized Medicine (Di.Bi.M.I.S.) Section of Cardio-Respiratory and Endocrine-Metabolic Diseases University of Palermo Palermo Italy.
authors.forename: Marco Calogero
authors.initials: MC
authors.lastname: Amato
authors.affiliation: Biomedical Department of Internal and Specialized Medicine (Di.Bi.M.I.S.) Section of Cardio-Respiratory and Endocrine-Metabolic Diseases University of Palermo Palermo Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Pizzolanti
authors.affiliation: Biomedical Department of Internal and Specialized Medicine (Di.Bi.M.I.S.) Section of Cardio-Respiratory and Endocrine-Metabolic Diseases University of Palermo Palermo Italy.
authors.forename: Vittoria
authors.initials: V
authors.lastname: Torregrossa
authors.affiliation: Biomedical Department of Internal and Specialized Medicine (Di.Bi.M.I.S.) Section of Cardio-Respiratory and Endocrine-Metabolic Diseases University of Palermo Palermo Italy.
authors.forename: Felicia
authors.initials: F
authors.lastname: Pantò
authors.affiliation: Biomedical Department of Internal and Specialized Medicine (Di.Bi.M.I.S.) Section of Cardio-Respiratory and Endocrine-Metabolic Diseases University of Palermo Palermo Italy.
authors.forename: Carla
authors.initials: C
authors.lastname: Giordano
mesh_terms: D000368:Aged; D001786:Blood Glucose; D016000:Cluster Analysis; D003924:Diabetes Mellitus, Type 2 / Q000175:diagnosis*; D005260:Female; D005749:Gastric Inhibitory Polypeptide / Q000097:blood; D054439:Ghrelin / Q000097:blood; D052216:Glucagon-Like Peptide 1 / Q000097:blood; D005947:Glucose / Q000378:metabolism; D006706:Homeostasis; D006801:Humans; D054795:Incretins / Q000097:blood*; D007333:Insulin Resistance; D008297:Male; D008875:Middle Aged; D010641:Phenotype
chemical_list: D001786:Blood Glucose; D054439:Ghrelin; D054795:Incretins; D005749:Gastric Inhibitory Polypeptide; D052216:Glucagon-Like Peptide 1; D005947:Glucose
keywords: Ghrelin; Glucagon‐like peptide‐1; Glucose‐dependent insulinotropic polypeptide