Origin of Cardiovascular Risk in Overweight Preschool Children

Abstract

IMPORTANCETo date, the relationship among adiposity, insulin resistance, and cardiovascular risk factors at the onset of overweight or obesity has been unexplored.OBJECTIVES To assess whether insulin resistance and metabolic abnormalities are detectable at the onset of obesity and to unravel the interplay among adiposity, insulin resistance, and other such abnormalities. DESIGN, SETTING, AND PARTICIPANTSThe Origin of Cardiovascular Risk in Overweight Preschool Children cohort study aimed to evaluate at the onset of obesity in preschool children the prevalence of metabolic abnormalities, including hypertension, dyslipidemia, impaired carbohydrate metabolism, and nonalcoholic fatty liver disease. Between July 1, 2011, and July 30, 2012, in the Rome municipality, 13 family pediatricians enrolled healthy children (age range, 2.0-5.8 years) in the study during their routine practice of growth monitoring. Clinical medical records of 5729 children were reviewed; 597 children manifested new-onset overweight or obesity as their body mass index changed from normal weight to overweight or obesity in the previous 12 months according to the International Obesity Task Force classification. Of them, 219 were studied. MAIN OUTCOMES AND MEASURESPatients with new-onset overweight or obesity underwent clinical laboratory testing, including oral glucose tolerance test, and ultrasonographic investigations of fatty liver and intimal medial thickness of the common carotid arteries, subcutaneous adipose tissue, and visceral adipose tissue. The homeostatic assessment model algorithm-insulin resistance was calculated. RESULTS Among the entire population (n = 5729), overweight increased from 7.0% at 2.0 years to 16.9% at 5.8 years, with corresponding figures of 1.1% to 2.9% for obesity. In total, 597 overweight or obese children (10.4%) were identified, and 219 of them (36.7%) were studied. Among the latter, 86 patients (39.3%) had at least 1 metabolic abnormality. Hypertension was diagnosed in 29 patients (13.2%), dyslipidemia in 55 patients (25.1%), impaired fasting glucose level in 7 patients (3.2%), and glucose intolerance in 6 patients (2.7%). Nonalcoholic fatty liver disease was diagnosed in 68 patients (31.1%).CONCLUSIONS AND RELEVANCE Cardiometabolic risk factors, including fatty liver, are detectable in preschoolers at the onset of overweight or obesity, despite short-term exposure to excess weight and reduced insulin sensitivity. Our findings suggest the need to screen for cardiometabolic abnormalities at an earlier age than is now recommended.

Reference ranges of HOMA-IR in normal-weight and obese young Caucasians

“…We demonstrate therewith and in keeping with a previous observation of us [6] that obesity starts affecting HOMA-IR very early in childhood. In the present series, we saw a progressively increase in HOMA-IR values in both sexes from 5 to 7 years of age even in normal-weight children.…”

“…The EarlyBird study 26, a prospective cohort study of 235 healthy children aged 5-14 years, reported a progressive increase in HOMA-IR by 7 years of age onward in normal-weight children [2]. Importantly, both studies [2,6] suggest that IR starts to increase years before the beginning of the pubertal development and findings from the present series confirm this observation. On the contrary, D'Annunzio et al [27] did not observe any agerelated difference of HOMA-IR values in 142 prepubertal normal-weight Italian children who were cross-sectionally evaluated.…”

“…Age, gender, and ethnicity mostly influence IR [3][4][5]. In obese young individuals, IR may exceed physiological values, especially at the time of the puberty, putting the subject at significantly increased risk of developing CMRFs [6,7].…”

High Body Mass Index in Infancy May Predict Severe Obesity in Early Childhood

“…3 In the Bogalusa Heart Study, in all children with a body mass index (BMI) ≥99th percentile, obesity persisted into adulthood. 4 Furthermore, obesity can lead to metabolic abnormalities before age 5 years, 5 and severe obesity in childhood carries short-, medium-, and longer-term cardiovascular risks that exceed those of their less-obese peers. 6 All of these factors suggest an elevated lifetime risk of cardiometabolic disease in children with severe obesity, with a proportion of these children at risk for requiring bariatric surgery as early as adolescence.…”

Comparison of body fat calculations by sex and puberty status in obese schoolchildren using two and four compartment body composition models

“…Increases in adiposity associated with childhood obesity is a risk factor for glucose intolerance, insulin resistance, dyslipidemia, non-alcoholic fatty liver disease, hypertension, heart attack, stroke and premature death (2)(3)(4)(5)(6). Although body mass index (BMI) is widely used as an index of body fat (BF), it is not a direct measurement of adiposity.…”