biostudies-literatureLee KMinistry of EducationKorea Ministry of Science and ICTNational Research Foundation of KoreaInstitute for Information and Communications Technology Promotione39401https://www.ebi.ac.uk/biostudies/studies/S-EPMC11535971biostudies-literatureUnknown10(20)<h4>Objective</h4>Although thyroid disease is a common condition, there is limited research examining the prevalence of thyroid disease over a long period of time, including both before and during the COVID-19 pandemic. Therefore, we aimed to investigate sociodemographic aspects that might be associated with thyroid disease and how its prevalence has varied during the pandemic.<h4>Methods</h4>We assessed the prevalence of thyroid disease among Korean adults by using data from the Korea National Health and Nutrition Examination Survey from 1998 to 2021. We evaluated weighted prevalence and β-coefficients with 95 % CI for factors such as age, sex, residential area, education level, household income, perceived stress level, weight change, occupation category, and body mass index groups.<h4>ReHeliyonNational trends in thyroid disease and COVID-19 pandemic-related factors, 1998-2021: A nationwide representative study in South Korea.PMC11535971RS-2024-00460379IITP-2024-RS-2024-00438239Yon DKPark JRhee SYKim HLee MLee KLee HSmith LSon YLopez Sanchez GFWoo SKoyanagi AChoi YDragioti EKang JRahmati MfalseNational trends in thyroid disease and COVID-19 pandemic-related factors, 1998-2021: A nationwide representative study in South Korea.<h4>Objective</h4>Although thyroid disease is a common condition, there is limited research examining the prevalence of thyroid disease over a long period of time, including both before and during the COVID-19 pandemic. Therefore, we aimed to investigate sociodemographic aspects that might be associated with thyroid disease and how its prevalence has varied during the pandemic.<h4>Methods</h4>We assessed the prevalence of thyroid disease among Korean adults by using data from the Korea National Health and Nutrition Examination Survey from 1998 to 2021. We evaluated weighted prevalence and β-coefficients with 95 % CI for factors such as age, sex, residential area, education level, household income, perceived stress level, weight change, occupation category, and body mass index groups.<h4>Re2024-01-01T00:00:00Z2024 Oct2026-07-16T13:16:03.085Z2025-04-04T18:54:01.125ZS-EPMC115359713950220710.1016/j.heliyon.2024.e39401