Effects of Amantadine on Postoperative Cognitive Dysfunction

Study Overview
=================
Brief Summary
-----------------
Post-operative cognitive dysfunction (POCD) is a fairly well-documented clinical phenomenon. Investigators will determine whether amantadine can reduce the occurrence of POCD in elderly patients with major abdominal surgery.

Detailed Description
-----------------
Patients who are 60 years old or older for laparoscopic abdominal surgery will be randomly assigned into two groups: 1) no-treatment group, and 2) amantadine-treated group. Each group will have 150 patients. In addition, investigators will need 90 subjects in the control group. The data of these control subjects will be used to normalize the data of the two studied groups to diagnose POCD. The subjects in control groups will also be elderly but without the exposure to anesthesia and surgery.

Official Title
-----------------
Effects of Amantadine on Postoperative Cognitive Dysfunction in Elderly Patients With Elective Abdominal Surgery

Conditions
-----------------
Postoperative Cognitive Dysfunction

Intervention / Treatment
-----------------
* Drug: Amantadine


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: major elective gynecological, prostate or bladder surgery patients who are ≥ 60 years old. the surgery is laparoscopic surgery and is expected to last for ≥ 2 hours under general anesthesia and the patient will stay in hospital for at least 7 days after surgery. lack of serious hearing and vision impairment and be able to read so that neurobehavioral tests can be performed. Exclusion Criteria: Patients are not expected to be alive for longer than 3 months. Mini-mental State Examination (MMSE) [18] score ≤ 23. history of dementia, psychiatric illness or any diseases of central nervous system. current use of sedatives or antidepressant. alcoholism and drug dependence. patients previously included in this study (for patients who have second intra-abdominal surgery during the study period). difficult to follow up or patients with poor compliance. uncontrolled hypertension (> 180/100 mmHg)

Ages Eligible for Study
-----------------
Minimum Age: 60 Years
Maximum Age: 100 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Two groups: one with amantadine treatment and the other with amantadine treatment.
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Amantadine treatment<br>To determine whether amantadine is effective in reducing the occurrence of postoperative cognitive dysfunction. | Drug: Amantadine<br>* patients will receive amantadine 100 mg by month 2 h before the induction of general anesthesia and then 100 mg each time, three times per day for 5 days.<br>|
| No Intervention: No-treatment<br>Patients will not receive any treatment. | |

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of patients with postoperative cognitive dysfunction (POCD) (POCD is a composite outcome measure) | The existence of POCD will be determined by Visual Verbal Learning Test based on the Rey's Auditory Recall of words, Concept Shifting Test, Stroop Color Word Interference Test and Letter-Digit Coding based on the Symbol Digit Substitution Test | At 7 days after the surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of patients with postoperative cognitive dysfunction (POCD) (POCD is a composite outcome measure) | The existence of POCD will be determined by Visual Verbal Learning Test based on the Rey's Auditory Recall of words, Concept Shifting Test, Stroop Color Word Interference Test and Letter-Digit Coding based on the Symbol Digit Substitution Test | At 3 months after the surgery | 
| Time for bowel function return after surgery |  | up to 2 weeks after the surgery | 
| Degree of increase of stress hormone | Adrenocorticotropic Hormone | Up to 5 days after the surgery | 
| Length of hospital stay |  | Up to 3 months after the surgery | 
| Degree of change in growth factor | Brain-derived neurotrophic factor and glial cell derived neurotrophic factor | Up to 5 days after the surgery |