Long-term trends in anemia prevalence before and after COVID-19 among non-pregnant adults in South Korea, 2010 to 2023

Anemia is a global public health concern, yet its long-term trends in the general adult population, particularly during the COVID-19 pandemic, remain unclear. This study analyzed long-term trends and risk factors for anemia among non-pregnant adults including the pandemic. We analyzed data from the Korea National Health and Nutrition Examination Survey conducted on non-pregnant adults. Anemia was defined as a hemoglobin level of <13 g/dL in males and <12 g/dL in females. The prevalence of anemia was assessed across the pre- (2010-2019), intra- (2020-2022), and post-pandemic (2023) using a weighted linear regression, and risk factors were evaluated using multivariable weighted logistic regression. About 68,696 non-pregnant adults (29,074 males [42.32%]) were included in the analysis from 2010 to 2023. The prevalence of anemia showed an increasing trend from 8.49% (95% confidence interval [CI], 8.20-8.78) in pre-pandemic to 11.23% (10.61-11.86) in intra-pandemic and 11.93% (10.86-13.00) in post-pandemic. A significant rise was observed during the intra-pandemic period, with adjusted odds ratio of 1.37 (95% CI: 1.21-1.56) compared to pre-pandemic years. Anemia prevalence tended to rise with age in males, whereas it reached its lowest point in females aged 50 to 59 years. Key risk factors included female sex, older age, underweight, lower household income, and no dietary supplement use. Anemia prevalence has risen steadily over the past decade and further escalated during the COVID-19 pandemic. Although sex-based patterns followed overall patterns, age-related trends varied by sex. These results emphasize the need for age- and sex-specific public health strategies and targeted interventions for vulnerable groups.