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.