Effect of Aging on Bariatric Surgery-induced Changes in Metabolism and Cognition

Study Overview
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Brief Summary
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The investigators hypothesize that the improvements in insulin sensitivity, beta (β)-cell function, and inflammation will be greater, and the improvement in sarcopenic obesity will be less, in younger versus older individuals after substantial weight loss induced by sleeve gastrectomy bariatric surgery.

Detailed Description
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With an aging population that is increasingly susceptible to obesity and obesity-related comorbidities including sarcopenia and diabetes, effective and safe treatment options tailored to the needs of older adults are imperative. While medication and lifestyle interventions generally fail to achieve sustained large-scale weight loss, bariatric surgery is the most effective long-term weight loss treatment for obese patients and improves many of the medical complications associated with obesity. Sleeve gastrectomy (SG) results in substantial weight loss and may be more appropriate for older adults due to its low rate of complications and mortality. Therefore, SG has been proposed as a reasonable primary treatment modality in older obese individuals, with a substantial recent increase in the number of interventions performed. Despite the potential benefits, very little is known of the physiologic and metabolic effects of bariatric surgery, including SG, on glucose homeostasis and muscle physiology in older adults. A fundamental understanding of the effects of excess adiposity and weight loss interventions is of profound importance, especially with emerging evidence that earlier treatment of obesity may delay/prevent many comorbidities. An underlying inflammatory state has been implicated in the pathogenesis of sarcopenia and insulin resistance and may provide an important connection to the age-related declines seen in older obese patients. Therefore, this study aims to evaluate the modifying effect of age and inflammation on the SG-induced changes in body composition, muscle physiology, and insulin sensitivity. This protocol will be conducted in two age cohorts (greater than 60 and less than 50 years old).

Official Title
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Effect of Aging on Bariatric Surgery-induced Changes in Metabolism and Cognition

Conditions
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Insulin Resistance, Cognitive Impairment

Intervention / Treatment
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* Procedure: Sleeve gastrectomy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 21-80 yrs old BMI ≥ 35 kg/m2 Undergoing laparoscopic sleeve gastrectomy (SG) Exclusion Criteria: Smokers Presence of diabetes mellitus Taking any medication that might affect metabolism Severe organ dysfunction Pregnant or breastfeeding Prior gastrointestinal surgery that might affect study results Unable or unwilling to follow the study protocol or any reason the research team believes the subject is not an appropriate candidate for this study Weight >450 pounds (Will be unable to fit on the DXA scanner)

Ages Eligible for Study
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Minimum Age: 21 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Age group 1<br>Age > 60 years old | Procedure: Sleeve gastrectomy<br>* Type of bariatric surgery<br>|
| Age group 2<br>Age < 60 years old | Procedure: Sleeve gastrectomy<br>* Type of bariatric surgery<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Insulin Sensitivity | Subjects will undergo a clamp procedure to assess insulin sensitivity at baseline and 15% weight loss after surgery | Change from baseline in Insulin sensitivity at 15% weight loss (up to 4 months after surgery) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Beta cell function | Subjects will undergo a mixed meal tolerance test at baseline and 15% weight loss | Change from baseline to 15% weight loss (up to 4 months after surgery) |