Mediating Effect of IADL and Depression in the Relationship Between Ability to Perform Movements and Death Preparation in Elderly with Osteoarthritis or Rheumatoid Arthritis.

: This study investigated the mediating effects of instrumental activities of daily living (IADL) and depression on the relationship between the ability to perform movements and death preparation among older adults with osteoarthritis (OA) or rheumatoid arthritis (RA). : This study is a secondary analysis of data from the Ministry of Health and Welfare of Korea's 5th (2020) survey of the elderly. It included 1483 elderly individuals with OA or RA. We measured the ability to perform movements, death preparation, IADL, and depression using validated scales. Hayes' PROCESS Macro for SPSS model 6 was used to determine the mediating effects. : Death preparation exhibited significant differences based on satisfaction with economic conditions, fall experiences, and suicidal ideation. A significant correlation existed between the ability to perform movements, death preparation, IADL, and depression. IADL demonstrated a significant mediating effect between the ability to perform movements and death preparation. However, depression did not exhibit a significant mediating effect. : IADL significantly mediates the relationship between movement ability and death preparation in elderly individuals with OA or RA. Lower movement ability was associated with higher death preparation and greater IADL dependence. However, contrary to expectations, depression did not show a significant mediating effect. These findings offer significant insights for developing interventions to enhance the quality of life and prepare for dignified death in elderly individuals with OA or RA. Future longitudinal studies are required to clarify the causal relationships and evaluate the efficacy of IADL enhancement programs.