THE ASSESSMENT OF GLUCOSE TOLERANCE AND INSULIN RESISTANCE IN OBESE CHINESE CHILDREN

Kwan EYW, Cheung PT, Yeung LPK, Low LCK

Department of Paediatrics, University of Hong Kong, Queen Mary Hospital, Hong Kong, SAR, China

 

Objective:  To assess glucose tolerance and insulin resistance in obese Chinese children using different indexes.

Methods: Oral glucose tolerance test (OGTT) was performed in children with body mass index (BMI) of 23 and above. Diabetes, impaired glucose tolerance (IGT), impaired fasting glucose (IFG) were defined using the WHO and ADA criteria. HbA1c was checked and insulin resistance was assessed using the homeostasis model assessment (HOMA-IR). 

Results:  Eighty-three OGTT were performed for 62 children aged between 7.8 to 18.9 years (31 males and 31 females) with mean BMI of 31.4(4.3). Four and thirteen children had 120 min BS≥11.1 and 7.8-11.0 mmol/L respectively. Two and thirteen children had IFG and IGT respectively. The degree of glucose tolerance (GT) was associated with severity of acanthosis and family history of diabetes (X2, p<0.005), but only weakly with BMI (X2, p = 0.053). HbA1c but not HOMA-IR increased with progressive glucose intolerance and BMI. Results for HOMA-IR were similar when values were transformed logarithmically. HOMA-IR but not HbA1c progressively increased with the degree of acanthosis (3.28± 2.16 versus 7.53± 5.35 for no and marked acanthosis, p=0.019).

 

BMI <30

BMI 30-35

BMI >35

P value

HbA1c

5.38±0.50

5.83±0.57

5.69±0.46

0.009

HOMA-IR

4.71±2.67

6.45±4.67

5.61±3.61

>0.05

 

 

Normal GT

IGT

2 hr >11.1

P value

HbA1c

5.5±0.4

5.9±0.7

6.2±0.98

0.01

HOMA-IR

4.94±3.30

6.88±4.79

7.73±2.58

>0.05

Conclusion:  Glucose intolerance is common in obese Chinese children, especially those with acanthosis and family history of diabetes. However, insulin resistance as assessed by the HOMA model does not correlate well with BMI and glucose intolerance.

 
1911