Background:
@EN Non-insulin dependent diabetes mellitus (NIDDM) is a disorder characterized by a strong genetic basis and familial aggregation. Earlier studies suggested that offspring of NIDDM patients have a particularly high risk of diabetes. In Caucasian
familial studies, it is reported that offsprings of NIDDM patients have a decreased insulin sensitivity as an early metabolic abnormality.
Although the majority of patients with NIDDM in Caucasian are obese, many Korean NIDDM patients are not obese and require insulin treatment for blood glucose control. Considering clinical differences between Korean and Caucasian NIDDM patients,
it
is
questionanable whether offsprings of Korean NIDDM patients have a decreased insulin sensitivity. The present study is planned to investigate the insulin sensitivity of offsprings of Korean NIDDM patients.
@ES Methods:
@EN Eleven offsprings who have at least 1 parent with NIDDM and age, sex, body mass index (BMI) matched 8 healthy control subjects were included in this study. All of them were males. We measured BMI and waist to hip circumference ratio (WHR) and
performed at standard oral glucose tolerance test (OGTT) and 2-hour euglycemic hyperinsulinemic clamp. In OGTT, plasma glucose, insulin, and C-peptide concentrations were determined at 0, 30, 60, 90 and 120 min. Insulin sensitivity was measured
by
2-hour euglycemic hyperinsulinemic clamp. Priming dose of insulin was infused for 10 min and then continuously infused at the rate of 40 mU/㎡/min for 110 min. The plasma glucose concentration was measured at five-minute intervals, and an
infusion
of
20% glucose was adjusted to maintain a constant plasma glucose concentration (5.0mmol/L). Blood was drawn at 0, 20, 40, 60, 80, 100, 120 min during glucose clamp, and plasma insulin, glucagon, and free fatty glucose amount during 80~120 min
divided
by
mean insulin concentration during 80~120 min ×100. Results were expressed as mean±S.E.M.. Student's t-test, Pearson's correlation and multiple regression analysis were performed to compare the results.
@ES Results:
@EN There were no significant differences in age sex, BMI< WHR, fasting plasma glucose, insulin, C-peptide and FFA levels between offsprings and controls. In OGTT, plasma glucose levels at 30 min, 60 min and 90 min in offsprings were
significantly
higher than controls (8.91±0.35 vs 6.93±0.35, p<0.001: 9.17±0.60 vs 6.41±0.56, p<0.05: 7.39±0.42 vs 5.82±0.51 mmol/L, p<0.05, respectively). All subjects of offsprings and controls had normal glucose tolerance. Plasma insulin and C-peptide
levels
in 0, 30, 60, 90, and 120 min were similar in both groups. In euglycemic hyperinsulinemic clamp, there was no significant difference in insulin sensitivity index between offsprings and controls (7.62±1.09 vs 8.05±0.87㎎/㎏/min/nU/ml×100,
p=0.760).
Insulin sensitivity index (M/I) was significantly associated with BMI (r=-0.69, p<0.01), WHR (r=-0.68, p<0.01). In multiple regression analysis, WHR had the most significant association with insulin sensitivity index.
@ES Conclusion:
@EN We could not find a decreased insulin sensitivity in offsprings of Korean NIDDM patients. We think that unimpaired insulin sensitivity of offsprings may be another different characteristics in Korean NIDDM patients compared to Caucasian NIDDM
patients.
|