The contribution of anthropometry, adiposity, and adiposopathy to cardiometabolic disturbances in obese youth

Adolescent Obesity and Eating Disorders: Can Calorie Restriction have a Positive Impact

Background:

The current obesogenic environment with relatively increased affordability and availability of high calorie food and beverages, has led to an alarming increase in the prevalence of obesity and related lifestyle disorders in children and adolescents, predisposing them to accelerated aging. The increased prevalence may be due to the eating behavior of adolescents, their genetic and molecular etiology and/or due to the impact of psychological stress and their wrong lifestyle choices. Calorie restriction has been extensively researched for reducing the obesity in adolescents and adults but is yet to be successfully implemented.

Objective:

The present review paper focuses on the types of calorie restriction diets, the role of its mimics and the nutrigenomic mechanisms that may be helpful in reducing obesity and related disorders in the adolescents. The role of behavioral therapeutic techniques and physical activity has also been highlighted in addition to the calorie restricted diet for bringing about an overall lifestyle modification in the management of obesity.

Conclusion:

Food preferences are acquired in childhood and sound nutritional practices should be established in childhood to prevent lifestyle disorders and premature aging. Though CR is a known and preferred non-pharmacological intervention in the management of obesity, its implemention has not been explored and evaluated extensively. This is a vital area that needs scientific research as the goals of obesity managements are no longer just weight loss through dietary restrictions. An interdisciplinary method to lifestyle modification in the management of adolescent obesity addressing all physiological and psychosocial aspects is recommended.

Waist circumference to height ratio and left ventricular mass in children and adolescents

OBJECTIVES

Waist circumference to height ratio, a measure of central obesity, is a better predictor of cardiovascular risk than body mass index in the paediatric population. Increased left ventricular mass secondary to obesity and hypertension increases the risk for death and cardiovascular disease in adults. Similar data on left ventricular mass are lacking among young patients with central obesity, as defined by waist circumference/height. The present study evaluates left ventricular mass in young patients with central obesity as defined by waist circumference/height.

METHODS

A total of 156 patients, 2- to 20-years old, without evidence of structural heart disease were studied. As the left ventricular mass is related to age and gender, 52 patients with central obesity - waist circumference/height ⩾0.55 - were randomly matched for age and gender with 52 patients at risk for central obesity - waist circumference/height ⩾0.5 to <0.55 - and 52 patients with no central obesity - waist circumference/height <0.5. The left ventricular mass parameters measured by echocardiography were compared across the three groups.

RESULTS

Patients with central obesity had significantly (p<0.05) increased Z scores for left ventricular mass, left ventricular mass/height2.7, and left ventricular mass/height1.7 compared with patients at risk for central obesity and patients with no central obesity. Z scores for left ventricular mass were higher among patients at risk for central obesity compared with patients with no central obesity.

CONCLUSIONS

Left ventricular mass data of the present study support maintaining an ideal waist circumference/height <0.5. Aggressive efforts to identify and manage patients with central obesity are warranted.

LMS tables for waist-circumference and waist-height ratio Z-scores in children aged 5-19 y in NHANES III: association with cardio-metabolic risks

BACKGROUND

In adults, anthropometric measures of central adiposity, such as waist-height ratio (WHtR) and waist circumference (WC), are more strongly associated with cardio-metabolic risks than BMI.

METHODS

To provide similar quantitative tools for North American children, we created smoothed centile charts and LMS tables for WHtR and WC based on data from the US National Health and Nutrition Survey, cycle III (NHANES III, N = 11,930 aged 2-24 y 1988-1994).

RESULTS

Applying these reference charts to subsequent NHANES survey cycles, 1999-2012) demonstrated a significant mean increase in both Z-scores of approximately 0.30 SD. In measuring the strength of the association between anthropometric measures and cardio-metabolic risk factors, a unit change in Z-scores for WHtR, WC, and BMI significantly increased the odds of an adverse outcome in all cases (1.18-2.03, P < 0.0001). Z-scores for both measures of central adiposity were significantly more strongly associated with cardio-metabolic comorbidities than BMI-Z.

CONCLUSION

Since Z-scores permit standardized comparisons across ages and genders, they are useful measures of central adiposity in both clinical or research settings. By providing LMS tables for children and adolescents based on North American reference data, we hope to provide quantitative tools for the study of obesity and its complications.

Adiposopathy and epigenetics: an introduction to obesity as a transgenerational disease

BACKGROUND

To examine the contribution of generational epigenetic dysregulation to the inception of obesity and its adiposopathic consequences.

METHODS

Sources for this review included searches of PubMed, Google Scholar, and international government/major association websites using terms including adiposity, adiposopathy, epigenetics, genetics, and obesity.

RESULTS

Excessive energy storage in adipose tissue often results in fat cell and fat organ dysfunction, which may cause metabolic and fat mass disorders. The adverse clinical manifestations of obesity are not solely due to the amount of body fat (adiposity), but are also dependent on anatomical and functional perturbations (adiposopathy or 'sick fat'). This review describes extragenetic factors and genetic conditions that promote obesity. It also serves as an introduction to epigenetic dysregulation (i.e., abnormalities in gene expression that occur without alteration in the genetic code itself), which may contribute to obesity and adiposopathic metabolic health outcomes in offspring. Within the epigenetic paradigm, obesity is a transgenerational disease, with weight lost or gained by either parent potentially impacting generational risk for obesity and its complications.

CONCLUSIONS

Epigenetics may be an important contributor to the emergence of obesity and its complications as global epidemics. Although transgenerational epigenetic influences present challenges, they may also present interventional opportunities, via justifying weight management for individuals before, during, and after pregnancy and for future generations.