Cardiometabolic risk factors and insulin resistance in obese children and adolescents: relation to puberty.
BACKGROUND
The prevalence of obesity with concomitant increasing risk for having cardiometabolic diseases is rising in the childhood population. Insulin resistance has a key role in metabolic changes in these children. Insulin levels elevate as puberty commences in every individual.


CONCLUSIONS
Children with increased risk for cardiometabolic diseases show significant differences in insulin levels even before the onset of puberty compared with those without risks. The pattern of appearance of dyslipidaemia also varies in children with risk factors even in the pre-pubertal group from those without risk. Children with metabolic syndrome display considerably pronounced changes in their metabolic parameters before the onset of puberty, which become more pronounced as puberty passes.


BACKGROUND
Insulin resistance (IR) has a key role in the metabolic changes in obese children. In commencing puberty, the insulin levels elevate. It is not clear, however, how insulin levels develop if the metabolic syndrome appears.


OBJECTIVE
Metabolic changes were assessed in obese children before, during and after puberty to analyse the relationship between IR and puberty in subjects with and without metabolic syndrome.


METHODS
Three hundred thirty-four obese children (5-19 years) attended the study. The criteria of the International Diabetes Federation were used to assess the presence of cardiometabolic risks (CMRs). Subjects with increased CMR were compared with those without risk (nCMR). Pubertal staging, lipid levels, plasma glucose and insulin levels during oral glucose tolerance test were determined in each participant. IR was expressed by homeostasis model assessment (HOMA-IR) and the ratio of glucose and insulin areas under the curve (AUC-IR).


RESULTS
Significantly higher AUC-IR were found in pre-pubertal CMR children compared with nCMR subjects (11.84 ± 1.03 vs. 8.00 ± 0.69; P < 0.01), but no difference was discovered during and after puberty. HOMA-IR differs between CMR and nCMR only in post-puberty (6.03 ± 1.26 vs. 2.54 ± 0.23; P < 0.01). CMR children have dyslipidaemia before the onset of puberty.


CONCLUSIONS
CMR is associated with increased postprandial IR in pre-pubertal and increased fasting IR in post-pubertal obese children. Dyslipidaemia appeared already in pre-puberty in CMR children.
St. John's and North-Buda United Hospitals of Budapest Municipality, Budapest, Hungary.
B
B
Tobisch
L
L
Blatniczky
L
L
Barkai
D000293:Adolescent; D001786:Blood Glucose / Q000378:metabolism*; D015992:Body Mass Index; D002648:Child; D050171:Dyslipidemias / Q000378:metabolism* / Q000503:physiopathology; D005260:Female; D005951:Glucose Tolerance Test; D006801:Humans; D007333:Insulin Resistance; D008297:Male; D024821:Metabolic Syndrome / Q000378:metabolism* / Q000503:physiopathology; D009765:Obesity / Q000378:metabolism* / Q000503:physiopathology; D015995:Prevalence; D011627:Puberty / Q000378:metabolism; D012307:Risk Factors
D001786:Blood Glucose
Insulin resistance; metabolic syndrome; obesity; puberty