Should low iron levels be treated or monitored with a watch and wait approach?

Management of Low Iron Levels: Treatment vs. Watch and Wait

Low iron levels should be treated rather than monitored with a watch and wait approach, particularly when iron deficiency is confirmed by laboratory testing, as treatment improves morbidity, mortality, and quality of life outcomes. 1

Diagnosis of Iron Deficiency

Before deciding on treatment, proper diagnosis is essential:

• Iron deficiency should be confirmed through laboratory testing:

  • Serum ferritin (primary marker)
  • Transferrin saturation (helpful when false-normal ferritin is suspected)
  • Complete blood count to assess for anemia
  • CRP to exclude acute phase reactions that can falsely elevate ferritin 1

• Diagnostic thresholds:

  • Adults >15 years: ferritin <30 μg/L
  • Adolescents 12-15 years: ferritin <20 μg/L
  • Children 6-12 years: ferritin <15 μg/L 2

Treatment Algorithm

1. Iron Deficiency Anemia (IDA)

When both low iron and anemia are present (Hb <13g/dL in men or <12g/dL in non-pregnant women, AND ferritin <45ng/mL):

• Immediate treatment is strongly recommended 1
• Investigate underlying cause (GI evaluation, celiac disease screening) 1
• Begin iron supplementation concurrently with investigations 1

2. Iron Deficiency Without Anemia

When ferritin is low but hemoglobin is normal:

• Treatment is recommended, especially with symptoms (fatigue, reduced cognitive function, headache, sleeping disorders) 1, 2
• Treatment prevents progression to anemia and improves quality of life 1
• The FERGImain study showed that proactive iron treatment prevents anemia recurrence 1

Treatment Options

Oral Iron Therapy

• First-line treatment: One tablet daily of ferrous sulfate, fumarate, or gluconate (providing 50-100mg elemental iron) 1
• If not tolerated: reduce to alternate-day dosing, which may improve absorption and reduce side effects 1
• Continue treatment for 3 months after normalization of hemoglobin to replenish iron stores 1
• Monitor hemoglobin response within 4 weeks of starting therapy 1

Parenteral (IV) Iron

Consider when:

• Oral iron is contraindicated, ineffective, or not tolerated 1
• Rapid iron repletion is needed 1
• Patient has conditions affecting iron absorption (inflammatory bowel disease, post-bariatric surgery) 1
• Patient has chronic inflammatory conditions (chronic kidney disease, heart failure) 1

Monitoring and Follow-up

• Check hemoglobin response within 4 weeks of starting treatment 1
• Continue iron therapy for 3 months after normalization of hemoglobin 1
• After successful treatment, monitor hemoglobin and iron indices every 3 months for one year, then annually 1
• For patients with recurrent iron deficiency, consider intermittent supplementation to maintain iron stores 2

Common Pitfalls to Avoid

1. Delaying treatment while awaiting investigations - Iron therapy should not be deferred unless colonoscopy is imminent 1

2. Ignoring non-anemic iron deficiency - Even without anemia, iron deficiency can cause significant symptoms and should be treated 1, 2

3. Excessive supplementation - Long-term daily oral or IV iron supplementation with normal/high ferritin is not recommended and potentially harmful 2

4. Inadequate duration of treatment - Failure to continue treatment for 3 months after hemoglobin normalization may lead to recurrence 1

5. Missing underlying causes - Always investigate the cause of iron deficiency, especially in men and postmenopausal women 1

The evidence strongly supports treating low iron levels rather than watching and waiting, as this approach improves clinical outcomes and quality of life while preventing progression to more severe deficiency states.