What are the common causes of melena in an elderly patient?

Causes of Melena in Elderly Patients

Most Common Etiologies in the Elderly

In elderly patients, peptic ulcer disease is the leading cause of melena, accounting for 35-50% of upper gastrointestinal bleeding cases, followed by gastroduodenal erosions (8-15%), esophagitis (5-15%), and Mallory-Weiss tears (approximately 15%). 1, 2

Upper Gastrointestinal Sources (Most Common)

• Peptic ulcer disease (gastric and duodenal ulcers) represents the most frequent cause, with gastric ulcers particularly predominant in elderly populations—accounting for 47% of cases in patients over 65 years 3, 2

• Gastroduodenal erosions cause 8-15% of cases and are commonly associated with NSAID use, which is particularly prevalent in elderly patients with chronic pain or arthritis 2

• Esophagitis accounts for 5-15% of cases and more frequently presents as coffee ground emesis rather than frank hematemesis 2

• Esophageal varices cause 5-10% of overall upper GI bleeding but should be strongly considered in elderly patients with known cirrhosis or chronic liver disease 2

• Mallory-Weiss tears represent approximately 15% of cases, typically occurring after forceful vomiting or retching episodes 2

• Cameron's erosions in large hiatal hernias are a commonly overlooked cause of melena in elderly patients with upper gastrointestinal symptoms 1

• Gastric antral vascular ectasia is particularly associated with chronic kidney disease and cirrhosis in the elderly population 1

• Dieulafoy's lesion accounts for 1-2% of acute bleeding and consists of a tortuous submucosal artery penetrating through the mucosa 2

Lower Gastrointestinal Sources (When Upper Endoscopy Negative)

• Diverticulosis is the most common cause of lower GI bleeding in elderly patients, representing 20-41% of cases, with incidence increasing dramatically with age (>200-fold increase from age 20 to 80 years) 4

• Angiodysplasia accounts for 3-40% of lower GI bleeding cases and up to 80% of obscure bleeding, particularly in patients over 40 years old 4, 1

• Ischemic colitis represents 10-21% of lower GI bleeding cases and is more common in elderly patients with cardiovascular disease 4

• Colorectal cancer or polyps account for 6-27% of cases, with higher prevalence in elderly populations 4

Small Bowel Sources (Obscure Bleeding)

• Angiodysplasia accounts for up to 80% of obscure small bowel bleeding in patients over 40 years old 1

• Small bowel tumors are less common in elderly patients compared to younger populations (where they are the leading cause under age 50) 1

• NSAID-induced ulcers in the small bowel are increasingly recognized as a cause of melena in elderly patients on chronic NSAID therapy 1

Age-Specific Considerations

Elderly patients (>65 years) have significantly higher mortality rates—up to 30% in those over 90 years—and require more aggressive management compared to younger patients. 4, 1

Critical Risk Factors in the Elderly

• Comorbidities are the strongest predictor of mortality, with deaths almost entirely restricted to patients with significant medical diseases including cardiovascular disease, renal failure, liver disease, and disseminated cancer 4

• Arteriosclerotic changes throughout the body decrease blood flow and organ function, making bleeding from gastric ulcers more difficult to control and increasing risk of irreversible shock 3

• Anticoagulation therapy (warfarin or direct oral anticoagulants) is more common in elderly patients and significantly increases bleeding risk 2

• Hemodynamic instability (pulse >100 bpm, systolic BP <100 mmHg) carries an 80% risk of continuing bleeding or death when combined with active ulcer bleeding 4

Diagnostic Approach Specific to Elderly Patients

• Esophagogastroduodenoscopy (EGD) should be performed within 24 hours of admission in hemodynamically stable elderly patients, as early specialist intervention reduces mortality 1

• Cap-fitted endoscopy should be used to examine blind areas (high lesser curve, under incisura angularis, posterior duodenal bulb) to improve diagnostic yield 1

• Colonoscopy should be performed if upper endoscopy is negative, as approximately 10-15% of patients presenting with melena have a lower GI source 4

• Capsule endoscopy should be considered if both EGD and colonoscopy are negative, as melena doubles the odds of finding a bleeding site in the proximal small intestine 1, 5

• Random duodenal biopsies for celiac disease should be obtained during endoscopy 1

Critical Management Pitfalls in Elderly Patients

• Never perform endoscopy before adequate resuscitation—this is a critical error that increases mortality in elderly patients with diminished cardiopulmonary reserve 1

• Avoid hyperventilation during resuscitation, as it is associated with increased mortality in hemorrhagic shock 1

• Maintain higher hemoglobin thresholds in elderly patients with cardiovascular comorbidities (>9 g/dL versus >7 g/dL in younger patients without comorbidities) 1

• Consider intubation before endoscopy in severely bleeding elderly patients to prevent pulmonary aspiration, given their decreased protective reflexes 1