The entire process is carried out according to Severance Hospital surgical protocols. The patients of control group will receive education from the research team about the importance of nutrition and exercise before and after surgery.

For the intervention group, the entire process is carried out according to the Severance Hospital surgical protocol, and the research team provides education before surgery on the importance of nutrition and exercise before and after surgery. In addition, the cognitive training program developed by Rowan is taught with the goal of performing it for at least 10 hours before the surgery, it is conducted the training program after the surgery.

The entire process is carried out according to Severance Hospital surgical protocols. The patients of control group will receive education from the research team about the importance of nutrition and exercise before and after surgery.

Confusion assessment methods(CAM) will be used to assess postoperative delirium at least two times a day during the hospitalization period. Patients diagnosed with delirium using the CAM were evaluated for the duration, symptoms, and type of delirium (e.g., reduced awareness of the environment; poor cognitive skills; behavioral changes, including hallucinations, restlessness, calling out, slowed movement, or lethargy; and emotional disturbances, such as anxiety, irritability, euphoria, apathy, unpredictable mood shift, and personality changes).

Core component of CGA are as follows : functional capacity, fall risk, cognition, mood, polypharmacy, social support, financial concerns, goals of care, and advance care preferences.