COVID-19 Outcomes in Busan: Impact of Area-Deprivation on Infection Risk by Gender and Age

This study investigated geographic inequalities in COVID-19 incidence by age and gender, in Busan, Korea, during the pandemic. We used multilevel Poisson regression to analyze 24,498 COVID-19 cases reported in Busan from February 2020 to December 2021, examining individual-level variables (age and gender) and are-level deprivation, along with their interactions. Each unit increase in the deprivation index was associated with a 9% increase in cases among men aged 20–64, a 2% decrease among women aged 20–64, an 8% increase among boys aged 0–9, and a 4% decrease among men aged ≥65 (p<0.001). There was no gender differences in overall COVID-19 incidence at ages 0–9 (p=0.213). The effect of deprivation on COVID-19 incidence was consistently stronger in men than women across all age groups (p=0.047 for the overall interaction). This pattern resulted in gender differences that varied by age: higher incidence rates at ages 0–9, 10–19, and ≥ 65, while women had higher rates at ages 20–64. Our findings highlight the importance of considering area-level deprivation and sociodemographic factors when designing public health interventions, as their interactions significantly influence COVID-19 incidence patterns and health inequalities in vulnerable populations.