Associations between insulin and glucose concentrations and anthropometric measures of fat mass in Australian adolescents.
BACKGROUND
One of the most serious, yet common co-morbidities of obesity is insulin resistance, which if untreated may progress to type 2 diabetes. This paper describes the insulin and glucose concentration distributions, the prevalence of elevated insulin, the associations between insulin and body mass index (BMI), waist circumference, waist-to-height ratio (WHtR) and fat mass index in a representative sample of Australian adolescents.


METHODS
Cross-sectional population-based study of adolescent boys and girls (N = 496, mean age 15.3 years) attending schools in metropolitan Sydney, Australia. Fasting venous blood collected and analysed for insulin and glucose concentrations. Height, weight, waist circumference measured, BMI and waist-to-height ratio calculated. Pubertal status self-reported.


RESULTS
Glucose concentrations were normally distributed and were not associated with adiposity. Insulin concentrations were distributed logarithmically, were higher among girls than boys overall and within the same ranges of BMI and waist circumference, but were lower among girls than boys within the same ranges of fat mass adjusted for height. The prevalence of elevated insulin concentration (defined as > 100 pmol/L) was 15.9% and 17.1% among boys and girls, respectively. Correlations between insulin concentration and BMI, waist circumference, WHtR and fat mass adjusted for height were 0.53, 0.49, 0.51 and 0.55, among boys, respectively, and 0.35, 0.40, 0.42 and 0.34, among girls, respectively.


CONCLUSIONS
Elevated insulin is highly correlated with adiposity in adolescents. BMI and WHtR are simple measures that can be used to identify young people who should be screened for insulin resistance and other co-morbidities.
Denney-Wilson
Elizabeth
E
University of New South Wales Research Centre for Primary Health Care and Equity, Sydney 2052, Australia. e.denney-wilson@unsw.edu.au
Cowell
Christopher T
CT
Okely
Anthony D
AD
Hardy
Louise L
LL
Aitken
Robert
R
Dobbins
Timothy
T
D050154:Adiposity; D000293:Adolescent; D001315:Australia; D001786:Blood Glucose / Q000032:analysis*; D001827:Body Height; D015992:Body Mass Index; D005260:Female; D006801:Humans; D007328:Insulin / Q000097:blood*; D008297:Male; D055105:Waist Circumference
D001786:Blood Glucose; D007328:Insulin