title: Characteristics of glucose metabolism in Nordic and South Asian subjects with type 2 diabetes.
abstract: BACKGROUND
  Insulin resistance and type 2 diabetes are more prevalent in people of South Asian ethnicity than in people of Western European origin. To investigate the source of these differences, we compared insulin sensitivity, insulin secretion, glucose and lipid metabolism in South Asian and Nordic subjects with type 2 diabetes.
  
  
  METHODS
  Forty-three Nordic and 19 South Asian subjects with type 2 diabetes were examined with intra-venous glucose tolerance test, euglycemic clamp including measurement of endogenous glucose production, indirect calorimetry measuring glucose and lipid oxidation, and dual x-ray absorptiometry measuring body composition.
  
  
  RESULTS
  Despite younger mean ± SD age (49.7 ± 9.4 vs 58.3 ± 8.3 years, p = 0.001), subjects of South Asian ethnicity had the same diabetes duration (9.3 ± 5.5 vs 9.6 ± 7.0 years, p = 0.86), significantly higher median [inter-quartile range] HbA1c (8.5 [1.6] vs 7.3 [1.6] %, p = 0.024) and lower BMI (28.7 ± 4.0 vs 33.2 ± 4.7 kg/m(2), p<0.001). The South Asian group exhibited significantly higher basal endogenous glucose production (19.1 [9.1] vs 14.4 [6.8] µmol/kgFFM · min, p = 0.003). There were no significant differences between the groups in total glucose disposal (39.1 ± 20.4 vs 39.2 ± 17.6 µmol/kgFFM · min, p = 0.99) or first phase insulin secretion (AUC0-8 min: 220 [302] vs 124 [275] pM, p = 0.35). In South Asian subjects there was a tendency towards positive correlations between endogenous glucose production and resting and clamp energy expenditure.
  
  
  CONCLUSIONS
  Subjects of South Asian ethnicity with type 2 diabetes, despite being younger and leaner, had higher basal endogenous glucose production, indicating higher hepatic insulin resistance, and a trend towards higher use of carbohydrates as fasting energy substrate compared to Nordic subjects. These findings may contribute to the understanding of the observed differences in prevalence of type 2 diabetes between the ethnic groups.
authors.affiliation: Department of Endocrinology, Morbid Obesity and Preventive Medicine, Oslo University Hospital, Oslo, Norway ; Hormone Laboratory, Oslo University Hospital, Oslo, Norway ; Faculty of Medicine, University of Oslo, Oslo, Norway.
authors.forename: Cecilie
authors.initials: C
authors.lastname: Wium
authors.affiliation: Department of Endocrinology, Morbid Obesity and Preventive Medicine, Oslo University Hospital, Oslo, Norway ; Hormone Laboratory, Oslo University Hospital, Oslo, Norway ; Faculty of Medicine, University of Oslo, Oslo, Norway.
authors.forename: Hanne Løvdal
authors.initials: HL
authors.lastname: Gulseth
authors.affiliation: Department of Endocrinology, Morbid Obesity and Preventive Medicine, Oslo University Hospital, Oslo, Norway ; Faculty of Medicine, University of Oslo, Oslo, Norway.
authors.forename: Erik Fink
authors.initials: EF
authors.lastname: Eriksen
authors.affiliation: Department of Endocrinology, Morbid Obesity and Preventive Medicine, Oslo University Hospital, Oslo, Norway ; Faculty of Medicine, University of Oslo, Oslo, Norway.
authors.forename: Kåre Inge
authors.initials: KI
authors.lastname: Birkeland
mesh_terms: D015502:Absorptiometry, Photon; D000328:Adult; D001208:Asia / Q000208:ethnology; D002153:Calorimetry, Indirect; D003924:Diabetes Mellitus, Type 2 / Q000208:ethnology* / Q000378:metabolism; D004734:Energy Metabolism; D005060:Europe / Q000208:ethnology; D005260:Female; D005947:Glucose / Q000378:metabolism*; D015309:Glucose Clamp Technique; D005951:Glucose Tolerance Test; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D007328:Insulin / Q000378:metabolism; D007333:Insulin Resistance; D008099:Liver / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D014807:Vitamin D / Q000032:analysis
chemical_list: D005947:Glucose; D006442:Glycated Hemoglobin; D007328:Insulin; D014807:Vitamin D