What is the trace level of Hemoglobin (Hb)?

From the Guidelines

The definition of anemia in adults is a hemoglobin (Hb) concentration of < 130 g/L for men and < 120 g/L for women, although recent proposals suggest considering women anaemic if Hb < 130 g/L, as most attain this figure if not iron deficient 1. When evaluating trace hemoglobin levels, it's essential to consider factors such as altitude, age, race, and smoking, in addition to sex, as these contribute to the interpretation of the normal range of Hb values, particularly in patients with chronic kidney disease (CKD) 1. Key points to consider include:

• The World Health Organisation definition of anaemia is a haemoglobin (Hb) concentration of < 130 g/L for men and < 120 g/L for women, but recent proposals suggest considering women anaemic if Hb < 130 g/L 1.
• Anaemia is common in patients presenting for surgery, with a prevalence of 31.1% in men and 26.5% in women, and can be caused by various factors, including acute or chronic blood loss, vitamin B12 or folate deficiency, and anaemia of chronic disease 1.
• All causes of anaemia should be investigated and corrected, particularly in patients scheduled for surgery, as anaemia can have significant implications for patient outcomes, including increased risk of hospitalizations, cardiovascular disease, cognitive impairment, and mortality 1.
• Hemoglobin concentration can be expected to increase by about 0.6 g/dL in women and 0.9 g/dL in men for each 1,000 m of altitude above sea level, which should be considered when interpreting Hb values 1.

From the FDA Drug Label

Using ESAs to target a hemoglobin level of greater than 11 g/dL increases the risk of serious adverse cardiovascular reactions and has not been shown to provide additional benefit

• Trace hemoglobin is not directly mentioned in the provided drug label. The FDA drug label does not answer the question.

From the Research

Trace Hemoglobin

• Hemoglobin concentration is a crucial parameter in diagnosing anemia, which is defined as a limited or insufficient functional red blood cell supply in peripheral blood 2
• According to the World Health Organization (WHO), anemia is defined as hemoglobin (Hb) levels <12.0 g/dL in women and <13.0 g/dL in men 3
• New lower limits of normal Hb values have been proposed, according to ethnicity, gender, and age 3
• Anemia can be classified into different types, including iron-deficiency anemia, which is defined as low hemoglobin due to low iron stores 4
• Iron deficiency is a common condition that affects approximately 2 billion people worldwide and 14% of adults in the US, and can progress to iron-deficiency anemia if left untreated 4

Diagnosis and Measurement

• Hemoglobin concentration is most commonly measured for anemia diagnosis, and methods to measure Hb are usually invasive (requiring a blood sample) 2
• However, advances in diagnostic and clinical chemistry have led to the development of new noninvasive methods for measuring Hb concentration 2
• Accurate diagnosis at the individual level is important to identify individuals who require treatment, and anemia prevalence estimates are often the impetus for national nutrition policies or programs 2
• Other biomarkers and tests, such as serum ferritin and transferrin saturation, can help to determine the severity and underlying causes of anemia 5, 4

Treatment and Management

• Iron therapy is essential when using erythropoietin to maximize erythropoiesis by avoiding absolute and functional iron deficiency 5
• Oral iron is typically first-line therapy for most patients with iron deficiency, while intravenous iron is indicated for patients with oral iron intolerance, poor absorption, or certain chronic inflammatory conditions 4
• Treatment of anemia depends on the underlying cause and etiology, and may involve addressing underlying conditions such as bleeding, impaired iron absorption, or inadequate dietary iron intake 6, 4