Influenza Vaccination Trends and Associated Factors Among Middle-aged Working Adults With an Elevated Cardiovascular Risk in Korea

Abstract

Background and Objectives: The development of atherosclerotic cardiovascular disease (ASCVD) in middle-aged working groups can be a major contributor to disability-adjusted life years. However, information regarding the current trends in influenza vaccination within this demographic group remains scarce. Thus, we aimed to investigate the recent 11-year trends in influenza vaccination and related factors among these populations in Korea. Methods: Of 42,879 individuals aged 40–64 years enrolled in the Korea National Health and Nutrition Examination Survey between 2010 and 2021, 35,323 were included. We investigated the yearly trend of influenza vaccination rate according to ASCVD risk and factors associated with being unvaccinated in the elevated ASCVD risk group (ASCVD risk score: ≥7.5%). Results: Among the 35,323 participants, 20,392 (57.7%) were classified into the elevated ASCVD risk group. Over the 11 years, the vaccination rate was significantly higher in the elevated ASCVD risk group than in the low ASCVD risk group (33.8% vs. 25.3%, p<0.001). Factors associated with the unvaccinated status in the elevated ASCVD risk group included younger age (<50 years; adjusted odds ratio, 1.61; 95% confidence interval, 1.31–1.98), male sex (1.43; 1.16–1.76), current smoker status (1.41; 1.13–1.76), residence in an urban area (1.19; 1.01–1.41), and having higher education (1.3; 1.04–1.64). Conclusions: One in 3 middle-aged working adults with an elevated risk of ASCVD received the influenza vaccination. Although the influenza vaccination rate was higher in participants with an elevated ASCVD risk than in those with low ASCVD risk, the vaccination rate was relatively unsatisfactory.