Australian Prescriber Podcast: Episode E121 – Iron Deficiency Without Anaemia

Release Date: December 20, 2021
Host: David Liu
Guest: Dr. Cecily Forsyth, Haematologist

Introduction

In Episode E121 of the Australian Prescriber Podcast, host David Liu delves into the often-overlooked condition of iron deficiency without anaemia. He is joined by Dr. Cecily Forsyth, a haematologist from the Central Coast, who authored an article on this topic in the December 2021 edition of Australian Prescriber. The discussion centers on the prevalence, implications, diagnosis, and management of non-anaemic iron deficiency.

Understanding Non-Anaemic Iron Deficiency

Dr. Forsyth emphasizes the significance of recognizing iron deficiency even in the absence of anaemia. She notes that while iron deficiency anaemia is widely acknowledged, the non-anaemic form is more prevalent and carries its own set of consequences.

Dr. Cecily Forsyth [00:47]:
"It matters because this population are at risk of going on to develop iron deficiency anaemia. And we know that iron deficiency anaemia causes problems for patients, for, for pregnant women, for the workforce, et cetera."

She highlights that identifying and addressing iron deficiency before it progresses to anaemia is crucial for preventing associated health issues. Moreover, emerging research, particularly from Japan, links non-anaemic iron deficiency to a range of symptoms affecting both physical and mental well-being.

Symptoms and Consequences

Non-anaemic iron deficiency is associated with various symptoms beyond fatigue and lethargy. Dr. Forsyth discusses how iron deficiency impacts mental health and neurological functions.

Dr. Forsyth [01:50]:
"Some of the studies ... have shown that this group of patients are prone to increased fatigue, increased lethargy, difficulty in concentrating and really quite interestingly, this mood disturbance with increased irritability and some depression, correcting the iron deficiency."

Additional conditions linked to iron deficiency include Restless Legs Syndrome and poor neurodevelopmental outcomes in infants born to iron-deficient mothers. The broader implications of iron deficiency encompass impacts on multiple organs involved in iron metabolism.

Prevalence in the Community

While iron deficiency is not the sole driver of widespread symptoms like fatigue and irritability, Dr. Forsyth acknowledges its contributory role, especially in specific populations.

Dr. Forsyth [03:06]:
"Probably not a large driver, but it's there."

She points out that in her region outside Sydney, factors like long commutes, financial stress, and the COVID-19 pandemic have exacerbated the prevalence of iron deficiency, presenting a potentially correctable factor amidst other non-reversible stressors.

Identifying Causes of Iron Deficiency

A thorough patient history is essential in diagnosing iron deficiency. Dr. Forsyth outlines key factors to consider:

• Menstruation: Heavy menstrual bleeding is a significant cause, especially in menstruating women. She advises evaluating the volume of blood loss, explaining to patients how even seemingly normal periods can deplete iron stores.

Dr. Forsyth [05:02]:
"We have to sort of put it in the context of why is this person iron deficient? What is their diet like? Have they got any red flags that would make us feel that we do need to investigate their gastrointestinal tract?"

• Dietary Habits: Modern diets with reduced red meat intake may contribute to lower iron levels.

• Medical Conditions and Medications: Conditions like celiac disease, and the use of medications such as anti-inflammatories and anticoagulants, can lead to iron loss or impaired absorption.

• Lifestyle Factors: Alcohol consumption and liver disease can mask iron deficiency by elevating ferritin levels, complicating diagnosis.

Dr. Forsyth [05:10]:
"Are there physiological reasons for why they are iron deficient or is it completely unexplained?"

Interpreting Iron Studies

Dr. Forsyth underscores the complexity of interpreting iron studies, emphasizing the need to consider the patient's overall clinical context.

Dr. Forsyth [08:04]:
"We actually have to look at the iron studies in the context of the patient in front of us."

Key points include:

• Ferritin Levels: Low ferritin typically indicates iron deficiency, but in inflammatory states or liver disease, ferritin may be elevated despite actual iron deficiency.

• Transferrin Saturation: A transferrin saturation below 20-30% can indicate iron deficiency, even if ferritin is misleadingly high.

• Mean Corpuscular Volume (MCV): A falling MCV can signal emerging iron deficiency before anaemia develops.

• Special Tests: Soluble transferrin receptors can aid in diagnosing iron deficiency in complex cases, though they are not reimbursed and have limitations in certain populations.

Special Populations: Heart Failure and Chronic Kidney Disease

Dr. Forsyth highlights the importance of identifying and treating iron deficiency in patients with heart failure and chronic kidney disease (CKD), where correction can lead to significant clinical benefits.

Dr. Forsyth [11:32]:
"There is increasing evidence that correction of iron deficiency in patients with heart failure improves symptoms and quality of life and reduces hospital admission."

In CKD patients, iron supplementation:

• Enhances the efficacy of erythropoiesis-stimulating agents.
• Reduces the need for blood transfusions.
• May offer cardiovascular benefits.

Strategies for Correcting Iron Deficiency

Correcting iron deficiency involves both dietary and supplemental approaches. Dr. Forsyth advocates for practical, cost-effective strategies:

• Dietary Modifications: While improving iron intake through diet is ideal, it is often insufficient as a standalone strategy.

• Oral Iron Supplementation: The first-line treatment, recommended to be taken every other day to enhance absorption.

Dr. Forsyth [12:51]:
"I tend to use a well absorbed and cheap iron preparation and ask the patients to take it second daily."

• Intravenous Iron: For patients who cannot tolerate oral iron or have absorption issues, modern intravenous preparations offer a rapid and effective solution with minimal side effects.

Dr. Forsyth [16:28]:
"The improvement in the iron that we have available on the market now has really made it very easy for patients to have intravenous iron done by their local practitioner very readily."

She cautions about potential side effects such as skin staining and advises selecting appropriate iron formulations based on individual patient needs.

Follow-Up and Monitoring

Monitoring the effectiveness of iron supplementation is crucial. Dr. Forsyth recommends:

• Reassessment Timeline: Check ferritin and haemoglobin levels approximately eight weeks after initiating therapy.

• Frequency of Monitoring: Varies based on the underlying cause. For instance, patients with ongoing blood loss may require more frequent evaluations.

Dr. Forsyth [18:36]:
"How often you need to monitor them depends upon what the cause of the iron deficiency was, how likely it is to reoccur."

She emphasizes addressing the root cause of iron loss to prevent recurrence and highlights that persistent iron deficiency often indicates occult gastrointestinal bleeding.

Conclusion

Dr. Forsyth's insights in this podcast episode shed light on the critical, yet frequently neglected, issue of iron deficiency without anaemia. By understanding its implications, recognizing its diverse presentations, and implementing effective diagnostic and treatment strategies, healthcare providers can significantly enhance patient well-being and prevent the progression to more severe health complications.

Dr. Forsyth [19:55]:
"People don't lose iron, they lose blood."

Host Closing Remarks:
David Liu concludes by acknowledging the valuable clinical pearls shared by Dr. Forsyth, reinforcing the importance of comprehensive clinical assessment in managing iron deficiency.

David Liu [20:06]:
"The views of the guests on the host on this podcast are there on and may not represent Australian prescriber or NPS medicine wise."

This episode serves as an essential resource for healthcare professionals seeking to deepen their understanding of non-anaemic iron deficiency and its impact on patient health. By implementing the discussed strategies, clinicians can better identify, treat, and manage this prevalent condition.