Women with alpha thalassemia silent and minor genotypes, in particular, would benefit from individualised management of ID supplementation, according to study results.
“Physiological anaemia during pregnancy may aggravate the anaemia symptoms in carriers of thalassemia minor genotypes, thus affecting maternal and foetal health and even causing long-term adverse effects on new-borns,” they write in Nutrition.
Prevalence of ID in patients with thalassemia varies according to the genotype, so while some are predisposed to mild or moderate anaemia others suffer from severe anaemia that can cause infant death, they explain.
“While infants with a-thalassemia major are usually stillborn or die quickly after birth, and infants with b-thalassemia major genotypes develop progressive haemolytic anaemia 3–6 months after birth and die before 5 years if untreated.”
Improve clinical outcomes
Thalassemia is an inherited disorder that inhibits haemoglobin (red blood cells) production and is treated with life-long blood transfusions and intravenous chelation therapy.
Alpha and beta variants are the most common subtypes and characterised by different clinical phenotypes, including haematological profile and anaemia rates.
Iron is important for foetal development and maternal health and supplementation is strongly advised during pregnancy to avoid deficiency, however recommendations do not extent to thalassemia carriers as treatment can lead to iron overload.
On the other hand, the study authors believe there should be more focus on the condition and its association to IDA to improve clinical outcomes.
“Few studies have shown that iron supplementation in carriers of thalassemia with IDA during the third trimester can benefit both mother and baby.”
Protocol
The difference in iron metabolism of pregnant women (PW) with various thalassemia genotypes were assessed to help develop a clinical reference for personalised management.
Subjects with a prenatal genetic diagnosis of thalassemia were recruited from medical facilities in Hainan Province, China. Most had never been screened for haematological parameters and thalassemia genes prior to pregnancy and therefore had received no professional advice on iron supplementation.
Anaemia and haematological parameters of 15,051 subjects were analysed, along with the plasma ferritin (PF) levels of 714 anaemic pregnant women (APW).
Inverse correlation
Analyses determined that, in most cases, anaemia in PW without thalassemia (183) was considerably lower than that of women diagnosed with the condition - with the exception of subjects with alpha silent or beta (CD26) genotypes.
Subjects with severe clinical phenotypes showed higher anaemia rates, while the five common alpha thalassemia genes caused the least severe haematology phenotype and lowest anaemia rate.
ID was higher among subjects with alpha thalassemia silent or minor genotypes but was associated with low ID (10.85%) in six common beta minor genotypes.
This demonstrates that “prevalence of IDA is inversely correlated to severity of haematological phenotype induced by thalassemia genotypes,” the authors’ comment.
Furthermore, APW subjects without thalassemia were more likely to be deficient in iron (87.43%), although those with anaemia and thalassemia had higher PF levels.
“We suggest that the iron load of APW with b-thalassemia minor genotypes should be monitored dynamically during iron supplementation, since most carriers do not develop ID and have high PF levels,” the authors conclude.
Source: Nutrition
Published online, November 17, 2022: http://doi.org/10.3389/fnut.2022.2005951
‘Prevalence of iron-deficiency anaemia in pregnant women with various thalassemia genotypes: Thoughts on iron supplementation in pregnant women with thalassemia genes’
Authors: M. Wang, et al.