Postoperative Cognitive DysfunctionNCT03147937
Cognitive Changes After Major Joint Replacement - Full Trial (Cognigram 2)
An observational study of Postoperative Cognitive Dysfunction and Cognitive Impairment, run by Dr. Stephen Choi at 1 site in Canada.
Trial summary
Patients assume that cognitive performance rapidly returns to baseline after anesthesia and surgery. Several studies have shown that one week after major non-cardiac surgery about 27% of patients have postoperative cognitive dysfunction (POCD) and 10% of patients at 3 months. Read more about this study
- Who is it for?
- Ages 50 years and older
- Conditions the study is for
- Postoperative Cognitive Dysfunction, Cognitive Impairment, Mild Cognitive Impairment
- What is being tested?
- Cognitive Testing
- How many people
- 505 participants
- Where
- 1 siteCanada
- Study dates
- 1 May 2017to Dec 2025
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 50 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Study population: Patients undergoing total hip arthroplasty (THA) or total knee arthroplasty (TKA) at the Holland Orthopedic and Arthritic Centre (HOAC) at Sunnybrook Health Sciences Centre (SHSC).
Who may be able to join
- All patients ≥ 50 years of age undergoing elective total hip or knee arthroplasty at Sunnybrook Health Sciences Centre
Who cannot join
- Lack of informed consent
- Inability to comply with study procedures or follow-up visits
- Patients with diagnosed dementia or those being treated with donepezil (Aricept®)
- Patients with severe cognitive impairment defined as baseline with a CBB score of equal to or less than 80 in at least one of the 4 CBB domains
- Patients with uncontrolled psychiatric diagnoses including schizophrenia, bipolar disorder, major depressive mood disorder
- Patients undergoing a second joint replacement \& previously enrolled in this study within the past 6 months
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Assessing Postoperative Cognitive Changes After Major Joint Arthroplasty: A Prospective Cohort Study
Patients assume that cognitive performance rapidly returns to baseline after anesthesia and surgery. Several studies have shown that one week after major non-cardiac surgery about 27% of patients have postoperative cognitive dysfunction (POCD) and 10% of patients at 3 months. Very few studies have assessed the incidence of POCD beyond 3 months. POCD significantly reduces quality of life. Identifying risk factors for POCD is important because it is associated with prolonged hospital stay, loss of independence, and premature retirement. There is an urgent need to measure and document the level of cognitive change associated with surgery with an easy to use tool, both prior to admission and after discharge. This information can be used to plan appropriate care paths and to identify or test the efficacy of potential new treatments to alter the negative trajectory.
Read the detailed description
Postoperative cognitive dysfunction (POCD) is thought to affect a significant proportion of patients after major surgery (up to 10% at 3 months). This is potentially a major public health issue because patients with POCD have prolonged hospital admission, loss of independence and mortality. Undoubtedly, if POCD is as prevalent and devastating as has been previously reported, the decision to undergo elective surgery should be influenced by the risk of developing POCD. Given the scope of the issue, the deficiencies in the literature surrounding POCD are concerning. There are many methodological issues with previous studies and the diagnosis of POCD in the perioperative period.
It is imperative that the true natures of postoperative cognitive changes are elucidated so that preoperative risk stratification can be appropriately determined. This will lead to care pathways and interventions that can modify any possible downward changes thereby reducing the negative impact on patients and the health care system.
Main Study Hypothesis: The incidence of postoperative cognitive changes in the joint arthroplasty population is influenced by:
- Occurrence of major acute postoperative complications (e.g., cardiac event, pulmonary embolus, renal failure, pneumonia, prosthetic joint infection)
- Pre-existing mild cognitive impairment (MCI)
- Post-operative delirium
- Pre-existing comorbid conditions with inflammatory states such as auto-immune disorders, coronary artery disease, obstructive sleep apnea, and auto-immune disorders
Study Objectives:
In patients undergoing primary total hip or knee arthroplasty the goals of this project are to:
- Establish cognitive trajectories after major lower extremity joint arthroplasty and the incidence of both post-operative delirium and POCD
- Test Main Study Hypothesis (see above)
- Conditions
- Postoperative Cognitive Dysfunction, Cognitive Impairment, Mild Cognitive Impairment, Delirium, Cognitive Decline, Cognitive Change
- Being tested
- Cognitive Testing
- Medical subject headings
- Postoperative Cognitive Complications, Cognitive Dysfunction, Delirium, Autoimmune Diseases, Inflammation
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Cognitive TestingOther
Computerized CogState Brief Battery (CBB), Cognigram, assesses changes in four cognitive domains including psychomotor function, attention, learning and memory, and working memory. The CBB is a computerized test based on card games that can be administered online
What is being measured
The primary outcome is the main question the study is designed to answer.
Proportion of patients with Cognigram score decreasing by > 2 SDs from baseline at 4.5
Proportion of patients with Cognigram score decreasing by > 2 SDs from baseline at 4.5
Measured: 4.5 months from baseline
Secondary outcomes (5)
Proportion of patients with Cognigram score decreasing between 1 and 2 standard deviations from baseline at 4.5 months
Proportion of patients with Cognigram score decreasing between 1 and 2 standard deviations from baseline at 4.5 months
Measured: 4.5 months from baseline
Effect of pre-operative MCI on postoperative cognitive changes at 4.5 months
Effect of pre-operative MCI on postoperative cognitive changes at 4.5 months
Measured: 4.5 months from baseline
Effect of pre-operative chronic inflammatory states on postoperative cognitive changes at 4.5 months
Effect of pre-operative chronic inflammatory states on postoperative cognitive changes at 4.5 months
Measured: 4.5 months from baseline
Effect of postoperative delirium on postoperative cognitive changes at 4.5 months
Effect of postoperative delirium on postoperative cognitive changes at 4.5 months
Measured: 4.5 months from baseline
Effect of postoperative complications on postoperative cognitive changes at 4.5 months
Effect of postoperative complications on postoperative cognitive changes at 4.5 months
Measured: 4.5 months from baseline
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted10 May 2017
- Study start1 May 2017
- Primary completionDec 2025 (estimated)
- Study completionDec 2025 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Postoperative Cognitive DysfunctionStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 505 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Dr. Stephen Choi
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor-investigator, Dr. Stephen Choi, Sunnybrook Health Sciences Centre
- Investigators
- Stephen Choi, MD,FRCPC,MSc, Principal investigator, Sunnybrook Research Institute
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT03147937
- Sponsor's protocol ID
- 040-2017
- Status last verified
- Sep 2025
- First submitted
- 8 May 2017
- Last updated
- 5 Sep 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Publications
Choi S, Avramescu S, Orser BA, Au S. Protocol for a prospective cohort study of assessing postoperative cognitive changes after total hip and knee arthroplasty in the Greater Toronto area. BMJ Open. 2019 Feb 24;9(2):e024259. doi: 10.1136/bmjopen-2018-024259.
PubMed 30804030
Study at a glance
From the registry record, last updated by the sponsor on 5 Sep 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Assessing Postoperative Cognitive Changes After Major Joint Arthroplasty: A Prospective Cohort Study
- ClinicalTrials.gov ID
- NCT03147937
- Acronym / sponsor ID
- 040-2017
- Conditions
- Postoperative Cognitive Dysfunction, Cognitive Impairment, Mild Cognitive Impairment, Delirium, Cognitive Decline, Cognitive Change
- Study type
- Observational
- Recruitment status
- Active, not recruiting
- Enrolment
- 505 participants (estimated)
- Lead sponsor
- Dr. Stephen ChoiUniversity, hospital or other
- Study start
- 1 May 2017 (actual)
- Primary completion
- Dec 2025 (estimated)
- Study completion
- Dec 2025 (estimated)
- First posted
- 10 May 2017 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Patients assume that cognitive performance rapidly returns to baseline after anesthesia and surgery. Several studies have shown that one week after major non-cardiac surgery about 27% of patients have postoperative cognitive dysfunction (POCD) and 10% of patients at 3 months. Very few studies have assessed the incidence of POCD beyond 3 months. POCD significantly reduces quality of life. Identifying risk factors for POCD is important because it is associated with prolonged hospital stay, loss of independence, and premature retirement. There is an urgent need to measure and document the level of cognitive change associated with surgery with an easy to use tool, both prior to admission and after discharge. This information can be used to plan appropriate care paths and to identify or test the efficacy of potential new treatments to alter the negative trajectory.
Detailed description
Postoperative cognitive dysfunction (POCD) is thought to affect a significant proportion of patients after major surgery (up to 10% at 3 months). This is potentially a major public health issue because patients with POCD have prolonged hospital admission, loss of independence and mortality. Undoubtedly, if POCD is as prevalent and devastating as has been previously reported, the decision to undergo elective surgery should be influenced by the risk of developing POCD. Given the scope of the issue, the deficiencies in the literature surrounding POCD are concerning. There are many methodological issues with previous studies and the diagnosis of POCD in the perioperative period.
It is imperative that the true natures of postoperative cognitive changes are elucidated so that preoperative risk stratification can be appropriately determined. This will lead to care pathways and interventions that can modify any possible downward changes thereby reducing the negative impact on patients and the health care system.
Main Study Hypothesis: The incidence of postoperative cognitive changes in the joint arthroplasty population is influenced by:
- Occurrence of major acute postoperative complications (e.g., cardiac event, pulmonary embolus, renal failure, pneumonia, prosthetic joint infection)
- Pre-existing mild cognitive impairment (MCI)
- Post-operative delirium
- Pre-existing comorbid conditions with inflammatory states such as auto-immune disorders, coronary artery disease, obstructive sleep apnea, and auto-immune disorders
Study Objectives:
In patients undergoing primary total hip or knee arthroplasty the goals of this project are to:
- Establish cognitive trajectories after major lower extremity joint arthroplasty and the incidence of both post-operative delirium and POCD
- Test Main Study Hypothesis (see above)
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
Who may qualify
- Ages
- 50 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- Patients undergoing total hip arthroplasty (THA) or total knee arthroplasty (TKA) at the Holland Orthopedic and Arthritic Centre (HOAC) at Sunnybrook Health Sciences Centre (SHSC).
Key inclusion criteria (1 listed)
- All patients ≥ 50 years of age undergoing elective total hip or knee arthroplasty at Sunnybrook Health Sciences Centre
Key exclusion criteria (6 listed)
- Lack of informed consent
- Inability to comply with study procedures or follow-up visits
- Patients with diagnosed dementia or those being treated with donepezil (Aricept®)
- Patients with severe cognitive impairment defined as baseline with a CBB score of equal to or less than 80 in at least one of the 4 CBB domains
- Patients with uncontrolled psychiatric diagnoses including schizophrenia, bipolar disorder, major depressive mood disorder
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Cognitive TestingComputerized CogState Brief Battery (CBB), Cognigram, assesses changes in four cognitive domains including psychomotor function, attention, learning and memory, and working memory. The CBB is a computerized test based on card games that can be administered online | Other | – |
Primary outcome
Proportion of patients with Cognigram score decreasing by > 2 SDs from baseline at 4.5
Time frame: 4.5 months from baseline
Proportion of patients with Cognigram score decreasing by > 2 SDs from baseline at 4.5
5 secondary outcomes
Proportion of patients with Cognigram score decreasing between 1 and 2 standard deviations from baseline at 4.5 months
Time frame: 4.5 months from baseline
Effect of pre-operative MCI on postoperative cognitive changes at 4.5 months
Time frame: 4.5 months from baseline
Effect of pre-operative chronic inflammatory states on postoperative cognitive changes at 4.5 months
Time frame: 4.5 months from baseline
Effect of postoperative delirium on postoperative cognitive changes at 4.5 months
Time frame: 4.5 months from baseline
Effect of postoperative complications on postoperative cognitive changes at 4.5 months
Time frame: 4.5 months from baseline
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 5 Sep 2025.
- Derived from this study: PubMed 30804030Choi S, Avramescu S, Orser BA, Au S. Protocol for a prospective cohort study of assessing postoperative cognitive changes after total hip and knee arthroplasty in the Greater Toronto area. BMJ Open. 2019 Feb 24;9(2):e024259. doi: 10.1136/bmjopen-2018-024259.
- Individual participant dataSharing planned: Undecided
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Stephen Choi, MD,FRCPC,MSc principal investigator
Sunnybrook Research Institute
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Postoperative Cognitive Dysfunction and Cognitive Impairment, run by Dr. Stephen Choi at 1 site in Canada.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 1 inclusion and 6 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: under way, not looking for participants, as of the sponsor's last update on 5 Sep 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Canada. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Proportion of patients with Cognigram score decreasing by > 2 SDs from baseline at 4.5 (time frame: 4.5 months from baseline). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT03147937, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 5 Sep 2025.