Risk Factors for Anemia in Silent Carrier or Minor α-Thalassemia

Silent carrier or minor α-thalassemia (α-thal) is generally considered asymptomatic or associated with mild anemia in only a few cases. However, it is not uncommon for individuals with these conditions to seek outpatient care because of anemia. Which factors contribute to the development of anemia in this population? We retrospectively observed the individuals at a general hospital in central China, a non-endemic area for thalassemia. A total of 142 participants confirmed by thalassemia genetic testing were enrolled, including 54 cases of silent carrier and 88 cases of minor α-thal. Among the participants, 88 cases (62%) were diagnosed with anemia, as their hemoglobin (Hb) concentrations were below the lower limit of the reference range recommended by the World Health Organization (WHO) for their respective gender and age groups. Multivariate analysis of anemia revealed that the -^SEA/αα genotype (P = 0.014, OR = 2.503, 95%CI: 1.203-5.204) was an independent risk factor for anemia and deserves proactive anemia management. Iron deficiency (serum ferritin <30 ng/ml) has not been identified as a risk factor, but it is found to have a high incidence (18.2%) in the anemic group and requires further investigation with a larger sample size in this population.