Ferritin Levels Redefined: Optimal Threshold for Women
Publication Title: Reevaluating Ferritin Reference Intervals: Defining Limits Based on Iron-Sufficient Population Studies, Clinical Relevance, and Healthcare Efficiency
Summary
- Question
- This study aimed to reevaluate ferritin reference intervals for women of childbearing age to determine an appropriate clinical decision limit (CDL) for diagnosing iron deficiency. Ferritin is a protein that stores iron, and its levels are commonly used to assess iron status. The researchers explored whether current diagnostic thresholds accurately identify iron deficiency in this population and sought to propose a more effective cutoff based on population studies, clinical relevance, and healthcare efficiency.
- Why it Matters
- Ferritin thresholds play a critical role in identifying iron deficiency, which can cause fatigue, impaired cognitive function, and complications during pregnancy. Current guidelines, such as the World Health Organization’s cutoff of 15 ng/mL, may underdiagnose iron deficiency in women of childbearing age. Revising these thresholds can improve early detection, reduce healthcare burdens, and enhance patient outcomes. The findings are relevant to clinicians, laboratory professionals, and policymakers tasked with optimizing diagnostic standards for iron deficiency screening.
- Methods
- The researchers conducted a prospective study involving 169 iron-sufficient, nonpregnant women aged 18 to 40 years. Participants were selected based on normal complete blood count (CBC) parameters and transferrin levels, ensuring physiological iron sufficiency. Serum ferritin levels were measured using the Elecsys assay, and statistical analyses excluded outliers to refine reference intervals. Additionally, a retrospective review of ferritin data from women aged 20 to 49 was conducted to assess the impact of raising diagnostic thresholds on healthcare systems.
- Key Findings
- The study established a ferritin reference interval of 19.7 to 133 ng/mL for iron-sufficient women, with a median ferritin concentration of 59.5 ng/mL. Analysis showed that a cutoff of 25 ng/mL better aligns with clinical and population data, identifying iron deficiency earlier without significantly increasing false positives. Raising the threshold from 15 ng/mL to 25 ng/mL doubled the number of positive screens, while a threshold of 50 ng/mL quadrupled them. The proposed 25 ng/mL cutoff balances clinical effectiveness and healthcare efficiency.
- Implications
- Adopting a 25 ng/mL ferritin cutoff for diagnosing iron deficiency in women of childbearing age could enhance early detection and treatment, improving health outcomes while avoiding unnecessary interventions. This threshold is supported by population studies and aligns with observed physiological markers of iron sufficiency. It provides a cost-effective approach for healthcare systems and offers clearer guidance for clinicians managing iron deficiency.
- Next Steps
- The authors recommend further collaboration between clinical and laboratory teams to refine ferritin reference intervals across diverse populations and assay platforms. They suggest additional studies to validate the proposed cutoff in broader patient groups and settings, ensuring its applicability and effectiveness in clinical practice.
- Funding Information
- This research was not supported by any external funding sources as explicitly stated in the paper. Yale University also provided funding and support for this research.
Full Citation
Kodger J, El-Khoury J, Yurtsever N. Reevaluating Ferritin Reference Intervals: Defining Limits Based on Iron-Sufficient Population Studies, Clinical Relevance, and Healthcare Efficiency. The Journal Of Applied Laboratory Medicine 2025, 11: 193-196. PMID: 41047906, DOI: 10.1093/jalm/jfaf151.
This AI-assisted summary has been reviewed and approved by at least one of the study's authors to ensure it accurately reflects the research.
Authors
Jillian Kodger
First AuthorNalan Yurtsever, MD
Last AuthorAssistant Professor of Laboratory Medicine