In patients aged 65 years and older, should we use the WHO hemoglobin cut‑offs (<13.5 g/dL for men, <12.0 g/dL for women) rather than our institution’s reference range of 10.9–14.3 g/dL to define anemia?

Use WHO Hemoglobin Cut-offs, Not Your Institutional Range

Your institutional reference range of 10.9-14.3 g/dL is inappropriately low and should not be used to define anemia in patients aged 65 years and older—you must use the WHO cut-offs (<13.0 g/dL for men, <12.0 g/dL for women) instead. 1

Why Your Institutional Range Is Problematic

Your institutional range has a lower limit of 10.9 g/dL, which would miss significant anemia and its associated mortality and morbidity risks. The British Society of Gastroenterology 2021 guidelines explicitly state that anaemia should be defined as hemoglobin below the lower limit of normal for the relevant population, but these institutional ranges should be aligned with WHO-defined lower limits 1. Your current range fails this alignment.

Evidence Supporting WHO Cut-offs in Older Adults

Mortality Data

• Men with hemoglobin 12.0-12.9 g/dL (mild anemia by WHO criteria) have 56% greater mortality risk, and those with hemoglobin <12.0 g/dL have 87% greater mortality risk compared to those with hemoglobin 14.0-14.9 g/dL 2
• Women with hemoglobin <11.0 g/dL show 32% greater mortality risk 2
• A large Taiwanese cohort (77,532 older adults) confirmed that WHO-defined anemia substantially increases all-cause mortality (HR 1.86 in men, HR 1.63 in women) and cancer mortality 3

Functional and Quality of Life Impact

Even hemoglobin levels just below WHO thresholds are associated with:

• Impaired activities of daily living (BADL, IADL)
• Reduced mobility (POMA scores)
• Worse nutritional status (MNA)
• Increased comorbidity burden (CIRS scores) 4

Importantly, these functional impairments occur even with "mild" anemia, not just severe anemia 4.

The Physiologic Fallacy

Many clinicians mistakenly believe lower hemoglobin is "normal" in aging. This is incorrect:

• Older adults with anemia show appropriately elevated erythropoietin levels, indicating physiologic recognition of inadequate oxygen-carrying capacity 5
• Over 80% of older adults with anemia have an identifiable cause when properly investigated 5
• Decreased hemoglobin in advanced age is pathological, not physiological 5

Clinical Algorithm for Your Institution

1. Immediately adopt WHO cut-offs: <13.0 g/dL for men, <12.0 g/dL for women aged ≥65 years
2. Any hemoglobin below these thresholds warrants:
   • Iron studies (ferritin, transferrin saturation) 1
   • Assessment for blood loss sources
   • Evaluation of nutritional deficiencies
   • Review of medications and chronic diseases
3. Consider investigation even at hemoglobin levels slightly above WHO cut-offs if accompanied by:
   • Functional decline
   • Unexplained fatigue
   • Iron deficiency on laboratory testing 1

Common Pitfall to Avoid

Do not accept hemoglobin of 11.0-12.9 g/dL in men or 10.0-11.9 g/dL in women as "normal for age." These levels are associated with increased mortality and functional impairment 4, 2, 3. Your institutional range would classify a 70-year-old man with hemoglobin of 11.5 g/dL as "normal," when he actually has anemia requiring investigation and treatment.

Optimal Hemoglobin Ranges for Survival

Research identifies optimal hemoglobin concentrations associated with lowest mortality:

• Men: 15.0-15.9 g/dL
• Women: 13.0-13.9 g/dL 3

This further emphasizes that your institutional lower limit of 10.9 g/dL is dangerously low.