Presentations

Abstract

Introduction: Iron deficiency anemia (IDA) is a significant public health concern across the world. While a recent study has reported a rising prevalence of anemia in the United States (US), recent time trends of prevalence of IDA and prevalence estimates by age, gender, race, and socioeconomic status are lacking. Therefore, the objective of this study was to examine the time trends of IDA prevalence in the general US population from 1999 to 2020 (22 years) and examine how these estimates differ by age, gender, race and household income by using a population cohort representative of the US population.

Methods: We used continuous NHANES data from 1999 to 2020. Patients self-reported their age, gender, race, and household income. The household income to poverty threshold ratio (HIPR) was calculated to account for changes in purchasing power during the study period. Blood samples were obtained for laboratory studies such as complete blood count, serum creatinine, serum ferritin, and serum c-reactive protein levels. The presence of IDA was determined by combining the World Health Organization criteria for anemia and serum ferritin levels <15 ng/mL and <150 ng/mL in the absence or presence of inflammation (CRP>1 mg/dL), respectively. Survey-weighted raw and adjusted prevalence rates (PR) were determined using generalized linear models for the overall population and by gender, age, race, and HIPR. Additionally, we examined if age modifies the relationship of gender with IDA.

Results: Of the 39,814 study participants, 62% were females, 10.5% were older than 65 years, 24.3% were African Americans, 31.4% were Hispanics, and35.9% were non-Hispanic Whites (Table 1). Unadjusted IDA prevalence in the population was 5.1% (males = 1.4%; females = 7.7%). IDA prevalence increased from 2.7% during the 1999-2000 survey cycle to 3.7% during 2017-20 (P=0.001). In adjusted analyses, IDA prevalence was higher in women than men (PR=5.78, 95%CI=4.50, 7.41), in Blacks than Whites (PR=3.83, 95%CI=3.22, 4.54), and in those with HIPR≤1 than >4 (PR=1.32, 95%CI=1.05, 1.68) but was similar across age groups (Table 2). Importantly, we found that age modified the relationship between gender and IDA prevalence.

Conclusion: The IDA prevalence in the US has risen from 1999 to 2020 and remains high among women, minorities, and those with lower income. The difference in IDA prevalence between men and women varies significantly by age.