Importance of iron-
Iron balance is essential for life.
The deficiency of iron is the depletion of total-body iron. As the largest amount of iron is consumed for hemoglobin (Hb) synthesis, anemia is an evident sign of iron deficiency. Iron deficiency is a broad term which indicates deficiency in organs/tissues other than those involved in erythropoiesis.
The cutoff for anemia is (Hb <13 g/dL in males, <12 g/dL in females, <11g/dL during pregnancy). Iron deficiency anemia has relevant impacts, such as impairment of cognitive performance in young children, adverse outcomes of pregnancy for both mothers and newborns, and cognitive decline in the elderly.
Causes of iron deficiency–
Nutritional iron deficiency arises when physiological requirements cannot be met by iron absorption from diet. Populations consuming monotonous plant-based diets with little meat have low dietary iron availability.
In meat, 30–70% of iron is haem iron, of which about 15–35% is absorbed. However, in plant-based diets most dietary iron is non-haem iron. The absorption is often less than 10%.
The risk of deficiency is highest when iron requirements are greater than needs. This happens in infants and young children, adolescents, and in menstruating and pregnant women.
The frequency of iron deficiency begins to rise in female adolescence, due to menstrual iron losses. 1 mL loss of blood translates into a 0∙5 mg loss of iron. Thus heavy menstrual blood loss (>80 mL per month) increases the risk for iron deficiency.
Other risk factors for iron deficiency include high parity and use of an intrauterine device.
During pregnancy, iron requirements increase three-fold because of growth of the fetal–placental unit. While during lactation, only about 0∙25 mg of iron per day is excreted into breastmilk, As most women are amenorrheic, iron requirement is low.
Individuals at risk–
- preschool children (age <5 years)
- young menstruating women
- women in the second/third trimester of pregnancy
- women in postpartum
What is Acquired iron deficiency?
Iron deficiency anemia is nutritional, that is it usually results from reduced intake of bioavailable iron. It is often associated with infections such as hookworm infestation or schistosomiasis. Iron depletion also results from chronic bleeding and/or reduced iron absorption.
Absolute iron deficiency may be masked in the elderly due to presence od additional comorbidities and also in cases of renal failure.
Diagnosing iron deficiency–
Signs and symptoms of iron deficiency anemia are often neglected. The most important symptom is fatigue. In long standing deficiency, symptoms of dry mouth, cheilitis, and hair loss are observed. Iron deficiency anemia may cause heart failure or angina in elderly.
Low serum ferritin levels are the hallmark in deficiency. Levels <30 mg/L are the accepted threshold that identifies mild cases. Ferritin levels are usually lower (<10-12 mg/L) if anemia co-exists.
Treatment of iron deficiency–
Oral iron supplementation
Iron salts such as iron sulfate, fumarate, and gluconate remain a mainstay of therapy in absolute iron deficiency
The alternative for patients intolerant or unresponsive to oral compounds is IV iron.
The high prevalence of iron deficiency in the developing world has substantial health and economic costs. It is thus important to provide additional dietary iron to susceptible infants and young children along with susceptible women age group.