1. To study whether there is a correlation between weakness and postoperative delusions in elderly non-cardiac surgery patients
2. Can the improved debilitating index predict the delusion after non-cardiac surgery
3. Which of the debilitating index are independent risk factors associated with postoperative delusions

Early identification of frailty patients is of great clinical significance for preoperative decision making and prognosis assessment. To date, the incidence of postoperative delirium in elderly patients undergoing noncardiac surgery has not been assessed. This study aimed to investigate the relationship between preoperative frailty assessment and the incidence of postoperative delirium after noncardiac surgery.

1. To study whether there is a correlation between weakness and postoperative delusions in elderly non-cardiac surgery patients
2. Can the improved debilitating index predict the delusion after non-cardiac surgery
3. Which of the debilitating index are independent risk factors associated with postoperative delusions

Inclusion Criteria:

1. Age ≥ 70 years old;
2. ASA: Grade Ⅰ～Ⅳ;
3. Signed informed consent；
4. Scheduled non-cardiac surgery.

Exclusion Criteria:

1. Refuse to participate;
2. Expected length of stay <3 days;
3. The same patient can only be included once, regardless of whether the reason for the second operation is related to the first cause;
4. Emergency surgery patients;
5. Inability to communicate due to illiteracy, language impairment, severe hearing or visual impairment;
6. Central nervous system diseases, including various types of dementia and depression
7. Severe renal insufficiency (requiring dialysis treatment);
8. Severe liver dysfunction (Child-Pugh score ≥10);
9. Patients who have participated in other relevant clinical studies within 3 months MMSE examination has confirmed the existence of cognitive dysfunction: illiteracy ≤17 points, primary school degree ≤20 points, middle school degree (including technical secondary school) ≤22 points, university degree (including junior college) ≤23 points

Patients older than 70 years undergoing non-cardiac surgery