HIV: human immunodeficiency virus.
* Refer to the UpToDate topic on the approach to the patient with unintentional weight loss.




Clinical Perspective

Body weight is determined by a person’s caloric intake, absorptive capacity, metabolic rate, and energy losses. Body weight normally peaks by the fifth or sixth decade and then gradually declines at a rate of 1–2 kg per decade.

Pivotal Assessment Findings
History 01. Healthy Dieting
02. Persistent restriction of energy intake
03. Recurrent Binge Eating
04. Diarrhea
05. Fever
06. Anorexia
07. Steatorrhea
08. Use of Weight Loss Medication
Hair Loss
Physical Exam 01. Tachycardia



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?


A 62-year-old man is brought to the clinic for a 3-month history of unintentional weight loss (12 lb). His appetite has diminished, but he reports no vomiting or diarrhea. He does report some depressive symptoms since the death of his wife a year ago, at which time he moved from Hong Kong to the United States to live with his daughter. He denies a smoking history. He complains of a 3-month history of productive cough with greenish sputum. He has not felt feverish. He takes no medications regularly. On examination, his temperature is 100.4°F and respiratory rate is 16 breaths per minute. His neck has a normal thyroid gland and no cervical or supraclavicular lymphadenopathy. His chest has few scattered rales in the left mid-lung fields and a faint expiratory wheeze on the right. His heart rhythm is regular with no gallops or murmurs. His abdominal examination is benign, his rectal examination shows no masses, and his stool is negative for occult blood. His chest x-ray is shown in Figure 80-1.



Content 4

A 77-year-old woman seeks your opinion because she has lost weight over the last 9 months. She reports her weight has fallen from 165 to 140 lb without any effort on her part to lose weight. She had a hip fracture after a fall 3 months ago that was successfully surgically repaired. She reports that her mobility is good. There are no fevers or night sweats. Her review of systems is otherwise negative, and she reports an intact but not voracious appetite. Medications include warfarin with a well-controlled INR. She is a lifelong nonsmoker and has one glass of wine less than twice per week. All of the following should be ordered to evaluate her involuntary weight loss EXCEPT:


The answer is D.  Involuntary weight loss (IWL) is frequently insidious and can have important implications, often serving as a harbinger of serious underlying disease. It is a common sign observed in outpatient practice, occurring in approximately 8% of all adult outpatients and 27% of the elderly or frail. Clinically important weight loss is defined as the loss of 10 lb (4.5 kg) or >5% of one’s body weight over a period of 6–12 months. This patient has lost approximately 20% of her body weight in 9 months and therefore merits further evaluation. Documentation of the weight loss (weight record, clothing size) is important because up to 50% of people who claim to have lost weight have no documented weight loss. Most patients with IWL have a malignant neoplasm, chronic inflammatory or infectious disease, metabolic disorder (e.g., hyperthyroidism and diabetes), or psychiatric disorder. Not infrequently, more than one cause is responsible. There is no identifiable cause of IWL in up to 25% of cases despite investigation. Based on this differential, initial evaluation should include a comprehensive history and physical examination, neurologic/cognitive/mood screening, medication review, appropriate cancer screening, and the laboratory examinations listed in the question. At this time, despite the increase in lung cancers in female nonsmokers, low-dose CT scan is not recommended as part of age-appropriate cancer screening. If lung cancer is suspected after the initial evaluation, a lung CT may be indicated at a later date. In this patient, bone density assessment is indicated given her recent hip fracture. It is likely that the hip fracture was related to the IWL.

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