The Effect of Circadian Clock System on Perioperative Cognitive Function of Elderly Patients

Study Overview
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Brief Summary
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Postoperative cognitive dysfunction (POCD) is a common postoperative complication in patients aged 65 and above. It refers to the cognitive function changes such as memory decline and attention loss after anesthesia and surgery. In serious cases, people may also experience personality changes and decline in social behavior ability, which will develop into irreversible cognitive impairment.Some studies reported that 25.8% of elderly patients presented POCD one week after non-cardiac surgery, and the incidence at 3 months after surgery was still 9.9%, which could increase the mortality in the first year after surgery.In recent years, studies have also proved that POCD is associated with patients' inability to perform their original jobs after non-cardiac surgery.Postoperative cognitive dysfunction seriously affects the clinical outcome, in addition to medical costs and other issues will bring an impact on the society and family.With the aging of the population, how to prevent cognitive dysfunction in elderly patients is a major challenge for perioperative management.There is a certain correlation between circadian rhythm and the dosage of general anesthesia, and postoperative sleep disturbance may be related to the effect of anesthesia and surgery on circadian rhythm.Preoperative sleep deprivation is known to be an independent risk factor for postoperative cognitive dysfunction (POCD), but the circadian mechanisms involved after general anesthesia are not yet clear

Official Title
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The Effect of Circadian Clock System on Perioperative Cognitive Function of Elderly Patients

Conditions
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Circadian Clock, Postoperative Cognitive Function, General Anesthesia, Elderly Patients

Intervention / Treatment
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* Other: receiving operation during the day or at night


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: preoperative sleep disorders did not receive any preoperative chemoradiotherapy the duration of surgery ≧3 hours Exclusion Criteria: History of schizophrenia epilepsy parkinson's disease or myasthenia gravis Critical illness (preoperative American society of anesthesiologists (ASA) ASA >III) severe liver insufficiency (ChildePugh grade C) severe renal insufficiency (preoperative dialysis) neurosurgery

Ages Eligible for Study
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Minimum Age: 65 Years
Maximum Age: 90 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Day group<br>60 patients scheduled for elective laparoscopic abdominal surgeries under general anesthesia were randomly assigned to receive operation in the Day Group ( 8:00-12:00) | Other: receiving operation during the day or at night<br>* 120 patients scheduled for elective laparoscopic abdominal surgeries under general anesthesia were randomly assigned to receive operation in the Day Group (8:00-12:00) and in the Night Group (18:00-22:00)<br>|
| Other: Night group<br>60 patients scheduled for elective laparoscopic abdominal surgeries under general anesthesia were randomly assigned to receive operation in the Night Group (18:00-22:00) | Other: receiving operation during the day or at night<br>* 120 patients scheduled for elective laparoscopic abdominal surgeries under general anesthesia were randomly assigned to receive operation in the Day Group (8:00-12:00) and in the Night Group (18:00-22:00)<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| postoperative sleep quality of one night before surgery | use sleep monitor to test the sleep quality one night before surgery | one night before the surgery | 
| postoperative sleep quality of first night after surgery | use sleep monitor to test the sleep quality first night after surgery | the first night after surgery | 
| postoperative sleep quality of third night after surgery | use sleep monitor to test the sleep quality third night after surgery | the third night after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Preoperative cognitive function test | use MMSE(Mini-mental state examination) scale to test the cognitive function one day before surgery. MMSE(Mini-mental state examination) is a simple test assessing several categories, such as orientation to time and place, short term memory, recall, attention, calculation, language and visuo-spatial abilities. Scores ranging from 30 to 24 usually indicate normal cognitive function, while lower scores suggest the presence of cognitive impairment: mild from 23 to 19, moderate from 18 to 10 and severe from 9 to 0 | one day before surgery | 
| Postoperative cognitive function test of 6 weeks after surgery | use MMSE(Mini-mental state examination) scale to test the cognitive function 6 weeks after surgery. MMSE is a simple test assessing several categories, such as orientation to time and place, short term memory, recall, attention, calculation, language and visuo-spatial abilities. Scores ranging from 30 to 24 usually indicate normal cognitive function, while lower scores suggest the presence of cognitive impairment: mild from 23 to 19, moderate from 18 to 10 and severe from 9 to 0 | 6 weeks after surgery | 
| Postoperative cognitive function test of 1 year after surgery | use MMSE(Mini-mental state examination) scale to test the cognitive function 1 year after surgery. MMSE(Mini-mental state examination) is a simple test assessing several categories, such as orientation to time and place, short term memory, recall, attention, calculation, language and visuo-spatial abilities. Scores ranging from 30 to 24 usually indicate normal cognitive function, while lower scores suggest the presence of cognitive impairment: mild from 23 to 19, moderate from 18 to 10 and severe from 9 to 0 | 1 year after surgery | 
| Postoperative cognitive function test of 3 years after surgery | use MMSE(Mini-mental state examination) scale to test the cognitive function 3 years after surgery. MMSE(Mini-mental state examination) is a simple test assessing several categories, such as orientation to time and place, short term memory, recall, attention, calculation, language and visuo-spatial abilities. Scores ranging from 30 to 24 usually indicate normal cognitive function, while lower scores suggest the presence of cognitive impairment: mild from 23 to 19, moderate from 18 to 10 and severe from 9 to 0 | 3 years after surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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circadian clock, postoperative cognitive function, general anesthesia, elderly patients