Clinical Presentation

The standardized measurement of weight appropriateness is the body mass index (BMI), which is validated in children older than 2 years of age. Before age 2 years, it is often useful to rely on a patient’s weight-to-height measurement. In adults (age 18 years and older), the term overweight corresponds to a BMI of 25 to 30, and a BMI of 30 or greater correlates with obesity. Throughout childhood, there is both an increase in weight and height, and it is therefore necessary to refer to BMI percentiles, which are adjusted for age and gender:

BMI is calculated using a formula (weight (kg) ÷ [height (m)]²⁾ or by using a BMI calculator, such as that provided by the Centers for Disease Control and Prevention (http://www.cdc.gov/healthyweight/assessing/bmi/index.html.) BMI should be calculated and plotted on the appropriate standardized graph to ascertain the BMI percentile at every well-child visit.

The history and physical examination of an obese patient should focus on identifying the problem, treatment options, and comorbidities. To assess for a patient’s risk for or diagnosis of obesity, one inquires about a patient’s lifestyle, including a general assessment of the patient’s dietary and eating habits, with particular attention placed on consumption of fruits and vegetables as well as high-calorie foods that are low in nutritional value, such as sweetened drinks, and an assessment of the patient’s daily screen time (both television and video games) and physical activity. Family history should include any first-degree relatives with obesity or common comorbidities of obesity, such as hypertension, cardiovascular disease, diabetes, and liver disease.

Laboratory evaluation such as fasting glucose, liver enzymes (alanine aminotransferase [ALT], aspartate aminotransferase [AST]), and fasting lipids are used to screen patients for the common comorbidities associated with obesity. Additional tests should be ordered based on the history and physical examination (Table 15-1).

Table 15-1 Evaluation for Comorbidities Associated with Obesity