Porth's Essentials of Pathophysiology, 4e

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Integrative Body Functions

U N I T 2

Binge-Eating Disorder Binge-eating disorder is characterized by eating too much in a short period of time, eating too fast, eating alone, eating when not hungry, and feeling uncomfort- ably full. Unlike bulimia nervosa, persons with binge eating do not engage in compensatory behaviors such as vomiting and laxative abuse. The great majority of persons with binge-eating disorder are overweight, and in turn, obese persons have a higher prevalence of binge- eating disorder than the nonobese populations. 56–59 The physical complications associated with binge-eating dis- orders are usually secondary to attendant obesity. The primary goal of therapy for binge-eating disorders is to establish a regular, healthy eating pattern. Persons with binge-eating disorders who have been successfully treated for their eating disorder have reported that mak- ing meal plans, eating a balanced diet at three regular meals a day, avoiding high-sugar foods and other binge foods, recording food intake and binge-eating episodes, exercising regularly, finding alternative activities, and avoiding alcohol and drugs are helpful in maintaining their more healthful eating behaviors after treatment. ■■ Undernutrition, which can range from a selective deficiency of a single nutrient to starvation, is among the most widespread causes of morbidity and mortality in the world. Protein-energy malnutrition in this population is commonly divided into two distinct conditions: marasmus, (protein and calorie deficiency) in which there is a great loss of protein from the skeletal muscle compartment; and kwashiorkor (protein deficiency), in which there is a greater loss of visceral proteins, particularly those of the liver. ■■ Malnutrition is also common during illness, recovery from trauma, and hospitalization.The effects of malnutrition and starvation on body function are widespread, including loss of muscle mass, impaired immunologic function and wound healing, decreased appetite, loss of calcium and phosphate from bone, anovulation and amenorrhea in women, and decreased testicular function in men. ■■ Eating disorders, which include anorexia nervosa, bulimia, and binge-eating disorder, are psychiatric disorders characterized by severe disturbances in eating, such as willful restriction of intake and binge eating, as well as excessive concern over body weight and shape. Anorexia nervosa is characterized by a refusal to maintain a minimally normal body weight; bulimia nervosa is characterized by secretive episodes of binging SUMMARY CONCEPTS

followed by compensatory behaviors such as self-induced vomiting; and binge eating disorder is characterized by the consumption of unusually large quantities of food in a short period of time that is not followed by compensatory behaviors.

R E V I EW E X E R C I S E S

1. Stability of body weight and composition over time requires that energy (food) intake match energy utilization. A. Define the terms hunger and appetite and describe their role in regulating food intake. B. Differentiate between short- and long-term

control of food intake and the neural and hormonal mechanisms involved in their regulation.

2. A 25-year-old woman is 65 inches (165 cm) tall and weighs 300 pounds (136 kg). She works as a receptionist in an office, brings her lunch to work with her, spends her evenings watching television, and gets very little exercise. She reports that she has been fat ever since she was a little girl, she has tried “every diet under the sun,” and when she diets she loses some weight but gains it all back again. A. Calculate her BMI using the website referred to in Table 10-1. B. How would you classify her obesity? C. What are her risk factors for obesity? D. What would be one of the first steps in helping her develop a plan to lose weight? 3. A 16-year-old high school student is brought into the physician’s office by her mother, who is worried because her daughter insists on dieting because she thinks she is too fat. The daughter is 67 inches tall and weighs 96 pounds. Her history reveals that she is a straight A student, plays in the orchestra, and is on the track team. She is given a tentative diagnosis of anorexia nervosa. A. What are the characteristic behaviors associated with anorexia nervosa? B. What are some of the physiologic manifestations of the malnutrition and severe weight loss associated with this disorder?

R E F E R E N C E S

1. Hall JE. Guyton and Hall’s Textbook of Medical Physiology . 10th ed. Philadelphia, PA: W.B. Saunders; 2011:843–858, 859–866. 2. Ross MH, Pawlina W. Histology . 6th ed. Philadelphia, PA: Wolters Kluwer Health/Lippincott Williams & Wilkins; 2011:254–264. 3. Casteilla L, Dani C. Adipose tissue-derived cells: from physiology to regenerative medicine. Diabetes Metab. 2006;32(5 pt 1):393–401.