1. Insulin resistance in prepubertal children
Vera Zdravkovic 1,2, Jovana Vuković2, Maja Jesic1,2, Vladislav Bojic1, Silvija Sajic1, 2.
University Children’s Hospital, Belgrade, Serbia1, University of Belgrade, School of medicine2
Results
Discussion
Introduction
Methods
The case-control study included 73 obese patients with BMI>2 SDS for age and gender
Study duration
Children were classified into prepubertal and pubertal group according to the Tanner staging criteria
BW and BL, breastfeeding duration,
eating patterns and family history of T2D
Height, weight, BP and fasting glucose, lipid profile, liver enyymes and oGTT
Our study showed a statistically significant difference in relation to age, gender,weight, height nd BMI between groups
Study revealed significantly higher cholesterol, LDL and HDL cholesterol,  CRP, AST and phosphorus levels in prepubertal children
Indices of insulin sensitivity and secretion between groups didn’t show a statistically significant difference
Insulin resistance was present in almost 80% of the patients according to the HOMA index. However,  lower values of HOMA, WBISI  and  higher IGI, were found in prepubertal subjects
Obesity in childhood is a risk factors for cardiovascular disease and type 2 diabetes (T2D) later in life
IR increase in puberty
Obese children in puberty are more insulin resistant than their peers, but are they IR before puberty onset?
(mmHg)
Prepubertal
Pubertal p
Systolic blood pressure
114.9±16.8
116.1±13.5
0.742
Diastolic blood pressure
72.6±10.5
74.7±9.5
0.386
mmol /L
Prepubertal 23
Pubertal 25 p
Glucose 0 min
5.2
( )
5.0
( )
0.327
Glucose 30 min
8.7
( )
8.4
( )
0.443
Glucose 60 min
6.8
( )
7.9
( )
0.164
Glucose 90 min
7.2
( )
7.1
(6-7.8)
0.821
Glucose 120 min
6.3
( )
6.4
( )
0.585
IDF criteria for the definition of metabolic syndrome   in children and adolescents
Biochemistry
Prepubertal
Pubertal p
HDL-c (mmol/l)
1.4±0.3
1.2±0.02
0.019*
LDL-c (mmol/l)
3.0±0.8
2.6±0.7
0.025*
Total cholesterol (mmol/l)
4.6±0.9
4.1±0.7
0.006*
Triglycerides (mmol/l)
1.2±0.8
1.2±0.6
0.984
ALT (u/l)
51.2±33.4
41.3±13.5
0.154
AST (u/l)
25.0±11.4
18.7±7
0.016*
HbA1c (%)
5.5±0.2
5.6±0.9
0.599
serum calcium (mmol/l)
2.4±0.1
0.121
serum phosphorus (mmol/l)
1.6±0.2
1.5±0.2
0.042*
CRP (mg/l)
3.9 ( )
2.2 ( )
0.009*
Indices of insulin sensitivity
Limit values
HOMA-IR
(insulin (μU/L) x glucose(mmol/L))/22,5
≥2.6
QUICKI
1/[log(insulin(μU/L))+log glucose ((mmol/L))]
≤0.33
WBISI
10 000/√ (fasting glucose × fasting insulin) x(glucose average ×insulin average)
≤ 2.5
IGI
Δinsulin (0-30 min)/ Δglucose (0-30 min)
<0.4
McA
exp ( ln ( insulin μU/L ) ln ( triglycerides mmol /L ))
≤5.8
μU/ml
Prepubertal 23
Pubertal 25 p
Insulin 0 min
16.0
( )
19.1
( )
0.831
Insulin 30 min
148.1
( )
128.1
( )
0.655
Insulin 60 min
93.5
( )
136.0
( )
0.404
Insulin 90 min
89.4
( )
112.3
( )
0.660
Insulin 120 min
79.7
( )
98.0
( )
0.271
AGE
CRITERIA
6-10 years
Obesity ≥90. percentile (WC)
10-16 years
Triglycerides ≥1,7 mmol/l (150 mg/dl)
HDL cholesterol <1,03 mmol/l (40 mg/dl)
Systolic pressure ≥130 mmHg or diastolic ≥85 mmHg
FPG ≥5.6 mmol / l (100 mg / dl) or known T2D
Conclusions
In our study  we have found a high prevalence of insulin resistance and lipid disorders in a group of obese children before puberty onset. This demand’s for early intervention to prevent the obesity at earlier stage.
Baseline characteristics 73
HOMA
58 (80%) 38
Prepubertal
30 (79%) 35
Pubertal
28 (80%) 48
WBISI
32 (67%) 23
13 (57%) 25
19 (76%) 69
McAuley
22 (32%) 36
10 (38%) 33
12 (36%)
Objectives
Characteristics
Prepubertal (38)
Pubertal (35) p
Age (y)
10.1±2.1
13.6±1.3
0.000*
Gender (M/F)
26 / 12
10 /25
0.001*
Height (cm)
153.1±13.6
166.4±7
Height SDS
2.1±1.5
1.2±1.4
0.006*
Weight (kg)
73.9±20.2
96.7±18.6
Weight SDS
3.3±0.9
3.5±0.9
0.353
BMI (kg/m2)
31.0±5.5
35.0±7
0.007*
BMI SDS
3.2±0.7
3.1±0.6
0.558
Indices of insulin sensitivity
Prepubertal
Pubertal p
Fasting glucose
5.3
( )
5.0
0.964
Fasting insulin
14.5
( )
19.2
( )
0.251
HOMA
3.5
( )
4.7
(2.6-6)
0.284
QUICKI
0.5
( )
WBISI
2.1
( )
2.2
( )
0.951
IGI
2.9
( )
( )
0.573
McA
6.5
(5.8-7)
6.1
(5.4-7)
0.313
to estimate the insulin resistance in obese children before puberty onset
to compare the indices of insulin resistance in prepubertal  and pubertal children
References
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