Factors associated with depression and suicidal ideation among oldest-old adults aged 85 years or older based on gender, using the survey data of South Korea

Background: South Korea is predicted to become a superaged society around 2025. Depression in older adults is a major factor influencing suicide. South Korea exhibits the highest suicide rate among the Organization for Economic Co-operation and Development countries. Methods: This study aimed to examine the factors associated with depression and suicidal ideation among individuals aged 85 years or older based on gender. Data were obtained from the Korea Institute for Health and Social Affairs, 2017. Overall, 768 individuals aged ≥85 years were included in the final analysis. The participants' general, health-related, and social characteristics were analyzed as factors influencing depression and suicidal ideation. Results: Among male oldest-old adults, living arrangements and the number of chronic diseases were factors affecting depression, while activities of daily living restrictions and the number of chronic diseases were factors affecting suicidal ideation. Among female oldest-old adults, only the number of chronic diseases affected depression, while financial status and the number of chronic diseases were the factors affecting suicidal ideation. Conclusions: The healthcare and welfare services for older adults must be expanded to cater to oldest-old adults who live alone, have activities of daily living restrictions, and have lower financial status. Additionally, the oldest age group's psychological health must be monitored regularly for depression and suicidal ideation to implement active interventions for this high-risk group.