The associations of body mass index, C-peptide and metabolic status in Chinese Type 2 diabetic patients

Diabet Med. 2004 Apr;21(4):349-53. doi: 10.1111/j.1464-5491.2004.01158.x.

Abstract

Background: Chinese Type 2 diabetic subjects are generally less obese than their Caucasian counterparts. We hypothesized that lean and obese Chinese Type 2 diabetic subjects have different metabolic and insulin secretory profiles. We compared the clinical features, C peptide and metabolic status between lean/normal weight and obese diabetic subjects.

Study design: We conducted a cross-sectional study on 521 consecutive diabetic subjects newly referred to a Diabetes Clinic in 1996. The subjects were categorized into underweight (< 18.5 kg/m(2)), normal weight (18.5-23 kg/m(2)) and overweight (>/= 23 kg/m(2)) according to the re-defined WHO criterion for obesity in Asia Pacific Region. Metabolic and anthropometric parameters were compared between groups with different levels of obesity.

Results: In this cohort, 5.8, 30.6 and 63.7% of subjects were underweight, normal weight and overweight, respectively, using the 'Asian' criteria. Of these 521 subjects, 20% had fasting C-peptide less than 0.2 nmol/l, suggesting insulin deficiency. Fasting C-peptide showed linear increasing trend (P < 0.001) while HbA(1c) showed decreasing trend (P = 0.001) with BMI after adjustment for duration of disease. There were more subjects in the underweight group who were treated with insulin (41.3% vs. 13.9 and 8.2%, P < 0.001). Although homeostasis model assessment was similar amongst the three groups, systolic (P = 0.006) and diastolic blood pressure (P < 0.001) and triglyceride (P < 0.001) showed increasing, while HDL-C (P < 0.001) showed decreasing, trends across different BMI groups. The underweight patients had the lowest C-peptide and highest HbA(1c) while overweight patients had the highest C-peptide, blood pressure, triglyceride but lowest HbA(1c) levels.

Conclusion: In Chinese Type 2 diabetic patients, lean subjects had predominant insulin deficiency and obese subjects had features of metabolic syndrome. Clinicians should have low threshold to initiate insulin therapy in lean Type 2 diabetic patients with suboptimal glycaemic control. In obese diabetic patients, aggressive control of multiple cardiovascular risks is of particular importance.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Body Mass Index*
  • C-Peptide / blood*
  • Cholesterol / blood
  • Cohort Studies
  • Cross-Sectional Studies
  • Diabetes Mellitus / blood*
  • Diabetes Mellitus / therapy
  • Diabetes Mellitus, Type 2 / blood*
  • Diabetes Mellitus, Type 2 / therapy
  • Female
  • Glycated Hemoglobin A / analysis
  • Hong Kong / ethnology
  • Humans
  • Insulin / blood
  • Male
  • Middle Aged
  • Obesity*
  • Patient Education as Topic

Substances

  • C-Peptide
  • Glycated Hemoglobin A
  • Insulin
  • Cholesterol