Quadrant -I (Video)
Assessment of obesity
Quadrant - II (Study Material)
1. Assessment of obesity
Assessment of Obesity: Before we consider assessment of obesity, it will be useful to first look at body composition as under: a. The active mass (muscle, liver, heart etc.) b. The fatty mass (fat) c. The extracellular fluid (blood, lymph, etc.) d. The connective tissue (skin, bones, connective tissue) The state of obesity is characterized by an increase in the fatty mass at the expense of the other parts of the body. The water content of the body is never increased in case of obesity. Although obesity can easily be identified at first sight, a precise assessment requires measurements and reference standards. The most widely used criteria are: BODY WEIGHT: Body weight, though not an accurate measure of excess fat, is a widely used index. In epidemiological studies it is conventional to accept + 2 SD (standard deviations) from the median weight for height as a cut-off point for overweight and + 3 SD for obesity. For adults, some people calculate various other indicators such as: (1) Body mass index (Quetelet's index): Body mass index (BMI) is a simple index of weight-for-height that is commonly used to classify underweight, overweight and obesity in adults. It is defined as the weight in kilograms divided by the square of the height in metres (kg/m²). For example, an adult who weighs 70 kg and whose height is 1.75 m will have a BMI of 22.9: BMI = 70 (kg) / 1.75² (m²) = 22.9. The classification of overweight and obesity, according to BMI, is shown in the following Table. Classification BMI Risk of comorbidities Underweight < 18.50 Low (but risk of other clinical problems increased) Normal range 18.50–24.99 Average Overweight ≥ 25.00 Pre-obese 25.00–29.99 Increased Obese class I 30.00–34.99 Moderate Obese class II 35.00–39.99 Severe Obese class III ≥ 40.00 Very severe Obesity is classified as a BMI ≥ 30.0. The classification shown is in agreement with that recommended by WHO but includes an additional subdivision at BMI 35.0–39.9 in recognition of the fact that management options for dealing with obesity differ above a BMI of 35. The WHO classification is based primarily on the association between BMI and mortality. (2) Ponderal index: = Height (cm) / Cube root of body weight (kg) (3) Brocca index: = Height (cm) minus 100 For example, if a person's height is 160 cm, his ideal weight is (160 – 100) = 60 kg (4) Lorentz's formula: = Ht (cm) – 100 – [Ht (cm) – 150 / 2 (women) or 4 (men)] (5) Corpulence index: = Actual weight / Desirable weight This should not exceed 1.2 The body mass index (BMI) and the Brocca index are widely used. WAIST CIRCUMFERENCE AND WAIST: HIP RATIO (WHR): Waist circumference is measured at the midpoint between the lower border of the rib cage and the iliac crest. It is a convenient and simple measurement that is unrelated to height, correlates closely with BMI and WHR and is an approximate index of intra-abdominal fat mass and total body fat. Changes in waist circumference reflect changes in risk factors for cardiovascular disease and other forms of chronic diseases. There is an increased risk of metabolic complications for men with a waist circumference ≥ 102 cm, and women with a waist circumference ≥ 88 cm. It has become accepted that a high WHR (> 1.0 in men and > 0.85 in women) indicates abdominal fat accumulation.
Quadrant - III (Assignments)
1. Assessment of obesity
Long Answer Questions on Assessment of Obesity and Cardiovascular Risk: Question 1 Describe the different methods used to assess obesity, including body mass index (BMI), waist circumference, and waist-hip ratio. How do these methods differ, and what are their respective advantages and limitations? Question 2 A 35-year-old male patient presents with a BMI of 32 kg/m2. Discuss the potential health risks associated with his obesity, including cardiovascular disease, type 2 diabetes, and certain types of cancer. Question 3 What is the role of waist circumference in assessing cardiovascular risk? How does waist circumference relate to visceral fat, and what are the implications for health outcomes? Question 4 Compare and contrast the World Health Organization's (WHO) BMI categories with other classification systems used to define obesity. How do these different systems impact the diagnosis and management of obesity? Question 5 Discuss the relationship between obesity and cardiovascular disease, including the underlying mechanisms and pathophysiological changes. How do factors such as insulin resistance, inflammation, and dyslipidemia contribute to cardiovascular risk? Question 6 A 40-year-old female patient with a history of hypertension and hyperlipidemia presents with a waist circumference of 95 cm. Discuss the implications of her central obesity for her cardiovascular health and management.