Weight Loss, Involuntary

Key Features

Essentials of Diagnosis

• Inquire about

  • Age; caloric intake; secondary confirmation (eg, changes in clothing size)

  • Fever; change in bowel habits

  • Substance abuse

  • Age-appropriate cancer screening history

General Considerations

• Body weight is determined by person's

  • Caloric intake

  • Absorptive capacity

  • Metabolic rate

  • Energy losses

• Involuntary weight loss is clinically significant when it exceeds 5% or more of usual body weight over a 6- to 12-month period

• Often indicates serious physical or psychological illness

• Most common causes

  • Cancer (~30% of cases)

  • Gastrointestinal disorders (~15%)

  • Dementia or depression (~15%)

• In approximately 15–25% of cases, no cause for the weight loss can be found

• In postmenopausal women, unintentional weight loss was associated with increased rates of hip and vertebral fractures

Clinical Findings

Symptoms and Signs

• History should include medication profile and 24-h diet recall

• Cancer

  • Night sweats

  • Cough

  • Breast mass

  • Constipation

  • Hematochezia

  • Bone pain

• Gastrointestinal disease

  • Nausea

  • Vomiting

  • Diarrhea

  • Abdominal pain

• Depression

  • Anhedonia

  • Sleep disorder

  • Suicidal ideation

  • Recent psychosocial stressors

• Dementia

  • Memory loss

  • Wandering

  • Isolation

• Physical examination for evidence of cancer

Differential Diagnosis

MEDICAL

• Malignancy

• Gastrointestinal disorders (eg, malabsorption, pancreatic insufficiency, peptic ulcer)

• Hyperthyroidism

• Chronic heart, lung, or renal disease

• Uncontrolled diabetes mellitus

• Mesenteric ischemia (ischemic bowel)

• Dysphagia

• Anorexia due to azotemia

• Hypercalcemia

• Tuberculosis

• Subacute infective endocarditis

• Frailty syndrome

PSYCHOSOCIAL

• Depression

• Dementia

• Alcohol use disorder (alcoholism)

• Anorexia nervosa

• Loss of teeth, poor denture fit

• Social isolation

• Poverty

• Inability to shop for or to prepare food

DRUG-RELATED

• Nonsteroidal anti-inflammatory drugs

• Antiepileptics

• Digoxin

• Selective serotonin reuptake inhibitors

Diagnosis

• Cause is usually revealed by

  • Complete blood count

  • Liver biochemical tests

  • Kidney tests

  • Serologic tests including HIV

  • Thyroid-stimulating hormone (TSH) level

  • Urinalysis

  • Fecal occult blood test

  • Chest radiography

• Age-appropriate cancer screening should be completed as recommended by guidelines (eg, Papanicolaou smear, mammography, FOBT/screening colonoscopy/flexible sigmoidoscopy, possibly prostate-specific antigen [PSA])

• Whole-body CT imaging is increasingly used for diagnosis

• When these tests are normal, the second phase of evaluation should focus on more definitive gastrointestinal investigation (eg, tests for malabsorption, endoscopy)

Treatment

Medications

• Appetite stimulants

  • Mild to moderate effectiveness in promoting weight gain

  • But no evidence of any decrease in mortality

  • May cause significant side effects

  • Agents used include

    • Corticosteroids

    • Progestational agents

    • Cannabinoids

    • Serotonin antagonists

• Anabolic agents

  • Growth hormone

  • Ghrelin

  • Testosterone derivatives

• Anticatabolic agents

  • Omega-3 fatty acids

  • Pentoxifylline

  • Hydrazine sulfate

  • Thalidomide

Therapeutic Procedures

• Treatment of the underlying disorder

• Consultation with dietician

• Caloric supplementation to achieve intake of 30–40 kcal/kg/day

• Oral feeding is ...