Workup of Unintentional Weight Loss in an Elderly Man
The appropriate workup for unintentional weight loss in an elderly man should include a comprehensive evaluation for malignancy, neuropsychiatric disorders, and benign organic diseases, as these account for the majority of cases, with cancer representing only 16.9% of diagnoses despite being a common concern. 1
Initial Assessment
History
- Quantify weight loss: ≥5% over 6 months or ≥10% beyond 6 months is considered significant 2
- Assess for:
- Changes in appetite or food intake
- Gastrointestinal symptoms (dysphagia, nausea, vomiting, abdominal pain)
- Neuropsychiatric symptoms (depression, anxiety, cognitive changes)
- Medication review (polypharmacy, recent medication changes)
- Social factors (living situation, access to food, ability to prepare meals)
Physical Examination
- Complete physical exam with focus on:
- Oral cavity (dentition, oral lesions)
- Thyroid examination
- Abdominal examination
- Lymph node assessment
- Neurological assessment including cognitive status
Laboratory Investigations
Based on evidence, the following tests should be included:
- Complete blood count 3
- Comprehensive chemistry panel 3
- Ultrasensitive thyroid-stimulating hormone 3
- Urinalysis 3
- Fecal occult blood test 3
Imaging and Diagnostic Procedures
- Gastrointestinal endoscopy (70.6% utilization rate in diagnostic workups) 1
- Colonoscopy (42.6% utilization rate) 1
- Computed tomography (44.1% utilization rate) 1
Tumor Marker Testing
While commonly ordered, tumor markers should be used selectively:
- PSA in men (81.8% utilization rate) 1
- CEA (80.9% utilization rate) 1
- CA 19-9 (65.4% utilization rate) 1
Common Causes to Consider
The diagnostic yield from studies shows the following distribution:
- Benign organic diseases (33.8%) 1
- Unknown causes (25.7%) 1
- Neuropsychiatric disorders (23.5%) 1
- Malignancy (16.9%) 1
Special Considerations
Medication Review
- Evaluate all medications for potential side effects that could contribute to weight loss
- Consider polypharmacy as a potential cause 3
- Review psychotropic medication changes that might unmask underlying issues 3
Nutritional Assessment
- BMI calculation (BMI <22 kg/m² in adults over 70 years is considered an indicator of malnutrition) 2
- Protein intake assessment (should be at least 1 g/kg body weight/day) 2
- Hydration status (minimum 1.6L for women, 2L for men daily) 2
Functional Assessment
- Evaluate ability to shop for and prepare food
- Assess for dysphagia or chewing difficulties
- Screen for sarcopenia and functional decline
Monitoring and Follow-up
- Weekly weight monitoring 2
- Monthly reassessment of nutritional interventions 2
- Regular follow-up to evaluate response to interventions 2
Important Caveats
- Unintentional weight loss is associated with increased morbidity and mortality, particularly when excessive (>5% body weight) 4
- A specific cause is not identified in approximately one quarter of elderly patients with unintentional weight loss 3
- The benefits of intentional weight loss observed in obesity studies do not apply to those with unintentional weight loss 5
- Sarcopenia and bone loss are important concerns in elderly patients with weight loss and should be monitored 5
Pitfalls to Avoid
- Focusing solely on malignancy when benign organic diseases are more common causes 1
- Neglecting neuropsychiatric causes, particularly depression, which is a leading cause of involuntary weight loss 3
- Overlooking social and functional factors that may contribute to weight loss
- Failing to distinguish between anorexia, dysphagia, weight loss despite normal intake, or socioeconomic problems 6
- Neglecting hydration needs when managing unintended weight loss 2