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Enrolling by Invitation

NCT Number: NCT05215886

Cognitive Impairment, Obesity, and the Effects of Bariatric Surgery

Study is designed to screen psychological cognitive baseline and retention/improvement after weight loss surgery.

Enrolling by Invitation

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Key information

Conditions

Obesity, Morbid Bariatric Surgery Candidate Body Weight Nutrition Disorders Nutritional and Metabolic Diseases Obesity Overnutrition Overweight Pathological Conditions, Signs and Symptoms Signs and Symptoms

Age range

18 year–75 year

Sex eligibility

All sexes

Study type

Observational

Primary location

University of California Davis Medical Center

Sacramento, California, 95817, United States

About this study

Patients with morbid obesity have shown to be at increased risk for memory loss and cognitive decline. Obesity and high-fat diets have been associated with deficits in learning, memory, and executive functioning. Bariatric surgery results in significant weight loss for patients and helps resolve obesity-related comorbidities such as diabetes and high blood pressure. Interestingly, bariatric surgery has shown promise in improving some aspects of cognitive function and improved memory. (3-1) Obesity affects brain structure, more specifically the grey and white matter, likely in part by reducing oxygen flow to the various regions in the brain. Studies have shown a correlation between BMI and cerebral blood flow velocity (CBFV), where higher BMI is associated with lower CBFV. Although it is not clear how exactly obesity plays a role in the brain's structural and functional changes, observations revealed compromised grey and white matter integrity, its fiber connectivity or cortical atrophy and metabolic alterations. (2)

Few studies exist on the impact of bariatric surgery on cognition. Some studies have shown that patients with obesity who underwent bariatric surgery had memory and cognitive improvement compared to those who had not undergone surgery. (4) Thus, the investigators hope to add to our understanding of how bariatric surgery can improve cognitive decline and to potentially offer surgery to more patients with baseline cognitive impairment and to improve cognitive function overall for patients with obesity. More longitudinal studies need to be done to connect bariatric surgery effects with cognitive decline, specifically memory.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Cognitive impairment/decline, memory impairment/loss, or Alzheimer's disease or dementia and bariatric surgery • Cognitive impairment/decline, memory impairment/loss, or Alzheimer's disease or dementia and obesity, and no bariatric surgery history

Exclusion criteria

  • Patients without a history of memory impairment/loss, bariatric surgery, or obesity
  • Patients outside of University of California Davis Health System
  • Patients unable to provide consent

Treatment and study plan

Surgery

Behavioral

Study subjects scheduled for or have already completed weight loss surgery and have already completed psychological screening as part of their pre-surgery work up

Primary outcomes

  1. California Verbal Learning Test-3rd Edition (CVLT-3)

    Time frame: Pre-operatively

    Measures episodic verbal learning including Verbal Learning, immediate memory, and delayed memory

  2. California Verbal Learning Test-3rd Edition (CVLT-3)

    Time frame: 12 Months after index screening/date of surgery

    Measures episodic verbal learning including Verbal Learning, immediate memory, and delayed memory

Secondary outcomes

  1. Brief Visuospatial Memory Test

    Time frame: Pre-operatively and 12 months after index screening/date of surgery

    Measures visuospatial learning and memory, including visual learning, immediate memory, and delayed memory.

  2. Brief Visuospatial Memory Test

    Time frame: Pre-operatively

    Measures visuospatial learning and memory, including visual learning, immediate memory, and delayed memory.

  3. Trial Making Test, A & B

    Time frame: 12 months after index screening/date of surgery

    Measures visual spatial attention, motor speed and cognitive flexibility

  4. WAIS-IV Digit Span Forward & Backward

    Time frame: Pre-Operatively

    Measures auditory Attention (Forward), and Auditory attention and working memory (Backward)

  5. WAIS-IV Digit Span Forward & Backward

    Time frame: 12 months after Index screening/date of surgery

    Measures auditory Attention (Forward), and Auditory attention and working memory (Backward)

  6. Verbal Fluency, Phonemic & Semantic

    Time frame: Pre-operatively

    Measures verbal fluency by a word generation task based on letter & category (executive functioning)

  7. Verbal Fluency, Phonemic & Semantic

    Time frame: 12 months after index screening/date of surgery

    Measures verbal fluency by a word generation task based on letter & category (executive functioning)

  8. Stroop Color and Word Test; Word, Color & Word-Color

    Time frame: Pre-Operatively

    Measures reading speed (word), naming speed (processing) and selective attention and inhibition (attention/executive functioning)

  9. Stroop Color and Word Test; Word, Color & Word-Color

    Time frame: 12 months after index screening/date of surgery

    Measures reading speed (word), naming speed (processing) and selective attention and inhibition (attention/executive functioning)

Sponsors and collaborators

Lead sponsor

University of California, Davis

Other

Registry information

Important dates

Study start
2022
Primary completion
2026
Study completion
2028
First posted
Jan 31, 2022
Registry last updated
Dec 5, 2025

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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