Trial Outcomes & Findings for Markers of Alzheimers Disease and Cognitive Outcomes After Perioperative Care (NCT NCT01993836)

NCT ID: NCT01993836

Last Updated: 2023-03-22

Results Overview

Spearman correlation was used here as the CSF markers follow a skewed distribution. Spearman correlation describes the strength of the monotonic relationship between two measures and is bounded between -1 and 1. Negative values indicate an inverse relationship while positive values mean that the variables move in tandem.

Recruitment status

COMPLETED

Study phase

PHASE4

Target enrollment

191 participants

Primary outcome timeframe

Baseline to 6 weeks

Results posted on

2023-03-22

Participant Flow

Participant milestones

Participant milestones
Measure
General Anesthesia With Isoflurane
Surgical patients randomized to receive inhalational anesthesia with isoflurane during surgery
Total Intravenous Anesthesia With Propofol
Surgical patients randomized to receive intravenous anesthesia with propofol during surgery
Non-Surgical Controls
Cohort of community dwelling healthy controls for tertiary comparison
Overall Study
STARTED
72
68
51
Overall Study
COMPLETED
55
55
46
Overall Study
NOT COMPLETED
17
13
5

Reasons for withdrawal

Reasons for withdrawal
Measure
General Anesthesia With Isoflurane
Surgical patients randomized to receive inhalational anesthesia with isoflurane during surgery
Total Intravenous Anesthesia With Propofol
Surgical patients randomized to receive intravenous anesthesia with propofol during surgery
Non-Surgical Controls
Cohort of community dwelling healthy controls for tertiary comparison
Overall Study
Surgery Cancelled
3
0
0
Overall Study
Physician Decision
2
1
0
Overall Study
Death
0
2
0
Overall Study
Withdrawal by Subject
12
10
5

Baseline Characteristics

Markers of Alzheimers Disease and Cognitive Outcomes After Perioperative Care

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure
General Anesthesia With Isoflurane
n=55 Participants
Surgical patients randomized to receive inhalational anesthesia with isoflurane during surgery
Total Intravenous Anesthesia With Propofol
n=55 Participants
Surgical patients randomized to receive iintravenous anesthesia with propofol during surgery
Non-Surgical Controls
n=46 Participants
Cohort of community dwelling healthy controls for tertiary comparison
Total
n=156 Participants
Total of all reporting groups
Age, Continuous
68.6 years
STANDARD_DEVIATION 6.1 • n=5 Participants
69.7 years
STANDARD_DEVIATION 6.9 • n=7 Participants
69.6 years
STANDARD_DEVIATION 7.6 • n=5 Participants
69.3 years
STANDARD_DEVIATION 6.8 • n=4 Participants
Sex: Female, Male
Female
17 Participants
n=5 Participants
24 Participants
n=7 Participants
18 Participants
n=5 Participants
59 Participants
n=4 Participants
Sex: Female, Male
Male
38 Participants
n=5 Participants
31 Participants
n=7 Participants
28 Participants
n=5 Participants
97 Participants
n=4 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants
n=5 Participants
0 Participants
n=7 Participants
0 Participants
n=5 Participants
0 Participants
n=4 Participants
Race (NIH/OMB)
Asian
0 Participants
n=5 Participants
0 Participants
n=7 Participants
1 Participants
n=5 Participants
1 Participants
n=4 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants
n=5 Participants
0 Participants
n=7 Participants
0 Participants
n=5 Participants
0 Participants
n=4 Participants
Race (NIH/OMB)
Black or African American
2 Participants
n=5 Participants
8 Participants
n=7 Participants
9 Participants
n=5 Participants
19 Participants
n=4 Participants
Race (NIH/OMB)
White
52 Participants
n=5 Participants
47 Participants
n=7 Participants
36 Participants
n=5 Participants
135 Participants
n=4 Participants
Race (NIH/OMB)
More than one race
0 Participants
n=5 Participants
0 Participants
n=7 Participants
0 Participants
n=5 Participants
0 Participants
n=4 Participants
Race (NIH/OMB)
Unknown or Not Reported
1 Participants
n=5 Participants
0 Participants
n=7 Participants
0 Participants
n=5 Participants
1 Participants
n=4 Participants
Region of Enrollment
United States
55 participants
n=5 Participants
55 participants
n=7 Participants
46 participants
n=5 Participants
156 participants
n=4 Participants
Baseline CSF levels
Tau
47 pg/ml
n=5 Participants
50 pg/ml
n=7 Participants
58.5 pg/ml
n=5 Participants
49 pg/ml
n=4 Participants
Baseline CSF levels
Abeta
369 pg/ml
n=5 Participants
352 pg/ml
n=7 Participants
330.5 pg/ml
n=5 Participants
347 pg/ml
n=4 Participants
Baseline CSF levels
P-Tau
26 pg/ml
n=5 Participants
28 pg/ml
n=7 Participants
21.0 pg/ml
n=5 Participants
25 pg/ml
n=4 Participants
Baseline CSF ratio levels
Tau/Abeta Ratio
0.13 ratio
n=5 Participants
0.14 ratio
n=7 Participants
0.16 ratio
n=5 Participants
0.14 ratio
n=4 Participants
Baseline CSF ratio levels
P-Tau/Abeta Ratio
0.08 ratio
n=5 Participants
0.08 ratio
n=7 Participants
0.06 ratio
n=5 Participants
0.07 ratio
n=4 Participants

PRIMARY outcome

Timeframe: Baseline to 6 weeks

Population: Analysis for the primary and secondary outcome 6 use the combination of both randomized treatment groups. The treatment groups are separated and compared in secondary analysis of outcomes 3-5, and the control group is only used in tertiary analyses. To be included in the outcome analysis patients must have returned for six-week follow-up visit.

Spearman correlation was used here as the CSF markers follow a skewed distribution. Spearman correlation describes the strength of the monotonic relationship between two measures and is bounded between -1 and 1. Negative values indicate an inverse relationship while positive values mean that the variables move in tandem.

Outcome measures

Outcome measures
Measure
Combined Surgical Cohort
n=110 Participants
The combination of both surgical randomized treatment groups.
General Anesthesia With Isoflurane
Patients in this arm will undergo general anesthesia with isoflurane as the primary amnestic agent. General anesthesia with isoflurane
Correlation Between Perioperative Change in Cerebrospinal Fluid (CSF) Markers of Alzheimers Disease and Perioperative Cognitive Change
Tau
-1.21 pg/ml
Interval -26.0 to 32.0
Correlation Between Perioperative Change in Cerebrospinal Fluid (CSF) Markers of Alzheimers Disease and Perioperative Cognitive Change
Abeta
-5.09 pg/ml
Interval -189.0 to 211.0
Correlation Between Perioperative Change in Cerebrospinal Fluid (CSF) Markers of Alzheimers Disease and Perioperative Cognitive Change
P-Tau
-0.44 pg/ml
Interval -31.0 to 85.0

PRIMARY outcome

Timeframe: Baseline to 6 weeks

Population: Analysis for the primary and secondary outcome 6 use the combination of both randomized treatment groups. The treatment groups are separated and compared in secondary analysis of outcomes 3-5, and the control group is only used in tertiary analyses. To be included in the outcome analysis patients must have returned for six-week follow-up visit.

Spearman correlation was used here as the ratio of CSF markers follow a skewed distribution. Spearman correlation describes the strength of the monotonic relationship between two measures and is bounded between -1 and 1. Negative values indicate an inverse relationship while positive values mean that the variables move in tandem.

Outcome measures

Outcome measures
Measure
Combined Surgical Cohort
n=110 Participants
The combination of both surgical randomized treatment groups.
General Anesthesia With Isoflurane
Patients in this arm will undergo general anesthesia with isoflurane as the primary amnestic agent. General anesthesia with isoflurane
Correlation Between Perioperative Change in Ratios of Cerebrospinal Fluid (CSF) Markers of Alzheimers Disease and Perioperative Cognitive Change
Tau/Abeta Ratio
0.001 ratio
Interval -0.2 to 0.21
Correlation Between Perioperative Change in Ratios of Cerebrospinal Fluid (CSF) Markers of Alzheimers Disease and Perioperative Cognitive Change
P-Tau/Abeta Ratio
0.002 ratio
Interval -0.1 to 0.41

SECONDARY outcome

Timeframe: Baseline to 6 weeks

Population: Analysis for the primary and secondary outcome 6 use the combination of both randomized treatment groups. The treatment groups are separated and compared in secondary analysis of outcomes 3-5, and the control group is only used in tertiary analyses. To be included in the outcome analysis patients must have returned for six-week follow-up visit.

To characterize cognitive function over time, while minimizing potential redundancy in the cognitive measures, a factor analysis was performed on the 10 cognitive test scores from baseline. To quantify overall cognitive function, a baseline cognitive index was first calculated as the mean of the preoperative domain scores. The cognitive index score has a mean of zero, thus any positive score is above the mean, any negative score is below the mean. A continuous change score was then calculated by subtracting the baseline from the 6-week cognitive index. A negative change score indicating decline and a positive score indicating improvement. The resulting outcome measure is unbounded with a standard deviation of 0.31 in the full surgical cohort.

Outcome measures

Outcome measures
Measure
Combined Surgical Cohort
n=55 Participants
The combination of both surgical randomized treatment groups.
General Anesthesia With Isoflurane
n=55 Participants
Patients in this arm will undergo general anesthesia with isoflurane as the primary amnestic agent. General anesthesia with isoflurane
Continuous Cognitive Index Score Change Difference Between Anesthetic Agent Groups
0.019 units on a scale
Standard Error 0.05
0.061 units on a scale
Standard Error 0.04

SECONDARY outcome

Timeframe: Baseline to 6 weeks

Population: Analysis for the primary and secondary outcome 6 use the combination of both randomized treatment groups. The treatment groups are separated and compared in secondary analysis of outcomes 3-5, and the control group is only used in tertiary analyses. To be included in the outcome analysis patients must have returned for six-week follow-up visit.

CSF Markers of Alzheimer's Disease over time in the subjects treated with propofol versus those treated with isoflurane.

Outcome measures

Outcome measures
Measure
Combined Surgical Cohort
n=55 Participants
The combination of both surgical randomized treatment groups.
General Anesthesia With Isoflurane
n=55 Participants
Patients in this arm will undergo general anesthesia with isoflurane as the primary amnestic agent. General anesthesia with isoflurane
Change in CSF Markers of Alzheimers Disease by Anesthetic Agent Group
Tau
-0.80 pg/ml
Interval -26.0 to 25.0
-1.67 pg/ml
Interval -25.0 to 32.0
Change in CSF Markers of Alzheimers Disease by Anesthetic Agent Group
Abeta
-2.10 pg/ml
Interval -189.0 to 211.0
-9.50 pg/ml
Interval -127.0 to 158.0
Change in CSF Markers of Alzheimers Disease by Anesthetic Agent Group
P-Tau
-2.25 pg/ml
Interval -31.0 to 49.0
1.10 pg/ml
Interval -25.0 to 85.0

SECONDARY outcome

Timeframe: baseline to 6-weeks

Population: Analysis for the primary and secondary outcome 6 use the combination of both randomized treatment groups. The treatment groups are separated and compared in secondary analysis of outcomes 3-5, and the control group is only used in tertiary analyses. To be included in the outcome analysis patients must have returned for six-week follow-up visit.

Change in ratio of CSF Markers of Alzheimer's Disease over time in the subjects treated with propofol versus those treated with isoflurane.

Outcome measures

Outcome measures
Measure
Combined Surgical Cohort
n=55 Participants
The combination of both surgical randomized treatment groups.
General Anesthesia With Isoflurane
n=55 Participants
Patients in this arm will undergo general anesthesia with isoflurane as the primary amnestic agent. General anesthesia with isoflurane
Change in Ratio of CSF Markers of Alzheimers Disease by Anesthetic Agent Group
Tau/Abeta Ratio
0.00 ratio
Interval -0.11 to 0.21
-0.00 ratio
Interval -0.2 to 0.13
Change in Ratio of CSF Markers of Alzheimers Disease by Anesthetic Agent Group
P-Tau/Abeta Ratio
-0.00 ratio
Interval -0.1 to 0.28
0.01 ratio
Interval -0.08 to 0.41

SECONDARY outcome

Timeframe: Baseline to 24 hours

Population: Analysis for the primary and secondary outcome 6 use the combination of both randomized treatment groups. The treatment groups are separated and compared in secondary analysis of outcomes 3-5, and the control group is only used in tertiary analyses. To be included in the outcome analysis patients must have returned for six-week follow-up visit.

The perioperative change in the CSF tau/Abeta ratio from the start of anesthesia/surgery to 24 hours later.

Outcome measures

Outcome measures
Measure
Combined Surgical Cohort
n=110 Participants
The combination of both surgical randomized treatment groups.
General Anesthesia With Isoflurane
Patients in this arm will undergo general anesthesia with isoflurane as the primary amnestic agent. General anesthesia with isoflurane
Perioperative CSF Tau/Abeta Ratio Change
-0.001 ratio
Interval -0.19 to 0.22

Adverse Events

General Anesthesia With Isoflurane

Serious events: 0 serious events
Other events: 2 other events
Deaths: 0 deaths

Total Intravenous Anesthesia With Propofol

Serious events: 0 serious events
Other events: 8 other events
Deaths: 2 deaths

Non-Surgical Controls

Serious events: 0 serious events
Other events: 7 other events
Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Other adverse events
Measure
General Anesthesia With Isoflurane
n=72 participants at risk
Surgical patients randomized to receive inhalational anesthesia with isoflurane during surgery
Total Intravenous Anesthesia With Propofol
n=68 participants at risk
Surgical patients randomized to receive iintravenous anesthesia with propofol during surgery
Non-Surgical Controls
n=51 participants at risk
Cohort of community dwelling healthy controls for comparison
General disorders
Fever
0.00%
0/72 • 6 weeks
1.5%
1/68 • Number of events 1 • 6 weeks
0.00%
0/51 • 6 weeks
Nervous system disorders
Headache
0.00%
0/72 • 6 weeks
1.5%
1/68 • Number of events 1 • 6 weeks
0.00%
0/51 • 6 weeks
Cardiac disorders
Vagal Event
1.4%
1/72 • Number of events 1 • 6 weeks
4.4%
3/68 • Number of events 3 • 6 weeks
3.9%
2/51 • Number of events 2 • 6 weeks
Respiratory, thoracic and mediastinal disorders
Shortness of Breath
0.00%
0/72 • 6 weeks
1.5%
1/68 • Number of events 1 • 6 weeks
0.00%
0/51 • 6 weeks
General disorders
Leg Pain and Swelling
1.4%
1/72 • Number of events 1 • 6 weeks
0.00%
0/68 • 6 weeks
0.00%
0/51 • 6 weeks
Nervous system disorders
Post-dural puncture headache
0.00%
0/72 • 6 weeks
1.5%
1/68 • Number of events 1 • 6 weeks
3.9%
2/51 • Number of events 2 • 6 weeks
General disorders
Back Pain
0.00%
0/72 • 6 weeks
1.5%
1/68 • Number of events 1 • 6 weeks
5.9%
3/51 • Number of events 5 • 6 weeks
Blood and lymphatic system disorders
Elevated PTT
0.00%
0/72 • 6 weeks
1.5%
1/68 • Number of events 1 • 6 weeks
0.00%
0/51 • 6 weeks
General disorders
Neck Stiffness
0.00%
0/72 • 6 weeks
1.5%
1/68 • Number of events 1 • 6 weeks
0.00%
0/51 • 6 weeks

Additional Information

Miles Berger, MD, PhD

Duke University

Phone: 919-684-8679

Results disclosure agreements

  • Principal investigator is a sponsor employee
  • Publication restrictions are in place