A 78-year-old Japanese man is brought in for evaluation of a 13-lb weight loss over the course of 6 months. He has moderate Alzheimer's dementia and dependency in all of his activities of daily living and lives in an assisted living facility. He reports a poor appetite and finds food "unappealing." The assisted living facility staff prepare all meals in a Western American cuisine style. The rest of his review of systems is negative with the exception of having discomfort with his dentures. His past medical history is significant for coronary artery disease, hypertension, and hypothyroidism. His medications include aspirin 325 mg daily, lisinopril 20 mg daily, metoprolol 25 mg twice daily, levothyroxine 100 μg daily, and donepezil 10 mg nightly.
- What additional questions would you ask to learn more about his weight loss?
- How would you classify his weight loss?
- What are possible causes of his weight loss?
- How can you distinguish between etiologies for weight loss?
Weight loss can be divided into 2 categories: involuntary or voluntary. Involuntary weight loss is a manifestation of cachexia associated with many disease states. Population studies have consistently shown increased mortality with involuntary weight loss even after adjusting for pre-existing illnesses and age.1,2 Voluntary weight loss, in the form of healthy dieting, is common among men and women. However, significant voluntary weight loss can herald a psychiatric illness such as an eating disorder, particularly among women. Anorexia is associated with a 12 times higher death rate among women aged 15 to 24 years.3 A careful history, physical examination, and directed diagnostic testing will suggest an etiology for weight loss in most patients.
|Anorexia||Loss of the desire to eat.|
|Anorexia nervosa4||Intense fear of gaining weight and refusal to maintain weight at or above a minimally appropriate weight for height and age.|
|Bulimia nervosa4||Recurrent episodes of binge eating followed by recurrent compensatory behavior to prevent weight gain (ie, laxative abuse and self-induced vomiting).|
|Cachexia||General muscle and/or fat wasting with malnutrition usually associated with chronic disease.|
|Involuntary weight loss||The unintended loss of weight; sometimes not reported by the patient and only noted upon chart review.|
|Malnutrition||Poor nutrition due to inadequate or unbalanced intake of nutrients or their impaired utilization.|
|Voluntary weight loss||The conscious effort to lose weight; frequently not a complaint among those with eating disorders.|
Weight loss is a nonspecific sign of many diseases. Most causes of involuntary weight loss belong to 1 of 4 categories: (1) malignancy, (2) psychiatric diseases, (3) chronic inflammation or infectious disease, and (4) metabolic disorders.5 Cancer is the most common cause of involuntary weight loss, accounting for 16% to 36% of cases. Psychiatric causes of involuntary weight loss (eg, depression) are also common.6 After healthy dieting, eating disorders (most commonly anorexia nervosa and bulimia nervosa) are the most common cause ...