Objectives: To investigate the demographic characteristics and insulin resistance in local overweight/obese Chinese children with and without acanthosis nigricans, and the associations of acanthosis nigricans with insulin resistance and other cardiometabolic co-morbidities.Design: Case series with cross-sectional analyses.Setting: A regional hospital in Hong Kong.Patients: Chinese children assessed between January 2006 and December 2010 at Tseung Kwan O Hospital for being overweight or obese. Main outcome measures:The demographics, anthropometric data, acanthosis nigricans status, and biochemical results were analysed.Results: A total of 543 overweight/obese children were studied with 64% being boys and 29% had insulin resistance. Adolescents aged 12 to 18 years, compared with children aged 5 to 11 years, were more likely to have acanthosis nigricans (63% vs 47%; P<0.001) and insulin resistance (37% vs 25%; P=0.005). Compared with overweight children, those who were obese were more likely to have the two conditions: acanthosis nigricans (59% vs 44%; P=0.005) and insulin resistance (35% vs 19%; P=0.001). Compared with those without acanthosis nigricans, those with the condition had significantly higher mean values for systolic blood pressures Acanthosis nigricans in obese Chinese children IntroductionObesity was formally recognised as a global epidemic by the World Health Organization (WHO) in 1997. 1During the past decades, the prevalence of being overweight and obese has increased substantially. In Hong Kong, 17% of children were overweight/obese in 2005/6, which was a 5% increase since 1993, based on International Obesity Task Force cut-offs. 2Overweight/obese children and adolescents are more likely to have hyperinsulinaemia, hypertension, and dyslipidaemia. 3 The clustering of cardiometabolic risk factors in these patients tends to track into adult life.3 However, the Diabetes New knowledge added by this study • Hong Kong Chinese children with acanthosis nigricans were more likely to have insulin resistance, hypertension, fatty livers, and abnormal glucose homeostasis. Implications for clinical practice or policy • In children, acanthosis nigricans is an important clinical sign warranting early attention and evaluation.

Aim: Childhood obesity is accompanied by an increased prevalence of abnormal glucose tolerance (AGT) including the prediabetes states. This study aims to investigate and evaluate the use of oral glucose tolerance test (OGTT) for detecting AGT among overweight and obese children. Methods: A retrospective study was conducted on 895 overweight and obese Chinese children (6–18 years) with obesity assessment and analysis of demographic, anthropometric, and biochemical parameters data between January 2006 and December 2015 at Tseung Kwan O Hospital, Hong Kong Special Administrative Region. Results: The proportion of males and older age group was 63.7% and 55.9%, respectively. Girls were more in older age groups (62.7% vs. 52.0%, P = 0.002). AGT occurred in 17.1% of the cohort [impaired glucose tolerance (IGT) was the most frequent morbidity (11.3%)]. After regression analysis, female sex, low-density lipoprotein (LDL), triglyceride (TG), older age group, and homeostasis model assessment of insulin resistance (HOMA-IR) ≥ 4.1 were significantly associated with AGT. Conclusions: AGT is common in overweight and obese Chinese children. Girls, older age, higher LDL, TG and HOMA-IR ≥ 4.1 showed significant association with AGT. OGTT is essential and fit-for-purpose to detect AGT in overweight and obese children.