Cognition in Patients With Hypoglycemia, Without Diabetes

Study Overview
=================
Brief Summary
-----------------
The purpose of this study is to determine if there is a relationship between recurrent hypoglycemia (low blood sugar) and cognition (thinking) in individuals who have a history of hypoglycemia, but do not have pre-diabetes or diabetes. This study will analyze whether recurrent hypoglycemia is associated with differences in cognition (thinking), and if individuals with a history of hypoglycemia perform less well on cognitive assessments compared to individuals without known hypoglycemia.

Detailed Description
-----------------
This study will test the hypothesis that recurrent hypoglycemia is associated with differences in cognition (thinking), by analyzing results of cognitive testing in individuals with a history of hypoglycemia as compared with those without known hypoglycemia. This pilot study will identify cognitive domains of interest in participants with hypoglycemia, as well as inform the development of a future battery of assessments, which could be replicated in a larger sample. Cognitive domains which will be assessed include: memory, language, executive function, and psychomotor speed.

Official Title
-----------------
Pilot Study - Cognition in Patients With Hypoglycemia, Without Diabetes

Conditions
-----------------
Hypoglycemia, Cognition

Intervention / Treatment
-----------------
* Other: Cognitive Assessment (not diagnostic)
* Diagnostic Test: ECG


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Age 18-70 years of age, inclusive, at screening. Willingness to provide informed consent and attend one study visit. For hypoglycemia after upper GI surgery group: Males or females diagnosed with ongoing post upper GI surgery hypoglycemia, with prior episodes of neuroglycopenia, unresponsive to dietary intervention. For hypoglycemia without a history of upper gastrointestinal surgery group: Males or females diagnosed with ongoing hypoglycemia with prior episodes of neuroglycopenia, and without a history of prediabetes, diabetes, or upper GI surgery. For post-bariatric without hypoglycemia group: Males or females with history of bariatric surgery, and no history of symptomatic hypoglycemia. For non-surgical controls only: Males or females with no history of upper GI surgery and no history of hypoglycemia, prediabetes, or diabetes. Exclusion Criteria: Active treatment with any diabetes medications, except for acarbose. History of cerebrovascular accident. History of a traumatic brain injury not related to hypoglycemia. Active depression. Active alcohol abuse or substance abuse. Known insulinoma, gastrinoma or other neuroendocrine tumor. Having undergone same / similar cognitive assessments within the last calendar year. There will be no involvement of special vulnerable populations such as fetuses, neonates, pregnant women, children, prisoners, institutionalized or incarcerated individuals, or others who may be considered vulnerable populations.

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 70 Years

Sexes Eligible for Study
-----------------
All

Study Plan
=================
How is the study designed?
-----------------

Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Hypoglycemia after upper gastrointestinal (GI) surgery<br>Participants with hypoglycemia after upper GI surgery, recruited from the Joslin Hypoglycemia Clinic and from other hypoglycemia studies at Joslin. | Other: Cognitive Assessment (not diagnostic)<br>* Cognitive testing will assess working memory and attention, verbal memory and delayed memory, executive function, and psychomotor speed.<br>Diagnostic Test: ECG<br>* ECG will take place during screening visit.<br>* Other names: Electrocardiogram (ECG);|
| Asymptomatic post-bariatric participants<br>Participants with a history of bariatric surgery, but without a diagnosis of hypoglycemia, or symptoms of hypoglycemia. They will be recruited by advertisement flyers at postoperative surgical clinics at local hospitals (e.g. Brigham and Women's and Beth Israel Deaconess Hospitals) and from other hypoglycemia studies at Joslin. | Other: Cognitive Assessment (not diagnostic)<br>* Cognitive testing will assess working memory and attention, verbal memory and delayed memory, executive function, and psychomotor speed.<br>Diagnostic Test: ECG<br>* ECG will take place during screening visit.<br>* Other names: Electrocardiogram (ECG);|
| Hypoglycemia no upper GI surgery & no diabetes (DM) or pre-DM<br>Participants with hypoglycemia and no history of upper gastrointestinal surgery, and NO current diagnosis of diabetes or pre-diabetes, recruited from the Joslin Hypoglycemia Clinic, or from other hypoglycemia studies at Joslin. | Other: Cognitive Assessment (not diagnostic)<br>* Cognitive testing will assess working memory and attention, verbal memory and delayed memory, executive function, and psychomotor speed.<br>Diagnostic Test: ECG<br>* ECG will take place during screening visit.<br>* Other names: Electrocardiogram (ECG);|
| Controls, no hypoglycemia or history of upper GI surgery<br>Participants without hypoglycemia or upper gastrointestinal surgery (controls), recruited by local advertisement. Some participants may be recruited from other hypoglycemia studies at Joslin. | Other: Cognitive Assessment (not diagnostic)<br>* Cognitive testing will assess working memory and attention, verbal memory and delayed memory, executive function, and psychomotor speed.<br>Diagnostic Test: ECG<br>* ECG will take place during screening visit.<br>* Other names: Electrocardiogram (ECG);|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Assessment of verbal memory | Rey Auditory Verbal Learning Test (RAVLT) immediate recall accuracy scores will be used to measure verbal memory. Scores will be compared between groups. Distributions of relevant variables will be examined for outliers and to determine appropriate statistics for use. Chi-square, Kruskal-Wallis, and analysis of variance (ANOVA) will be used to examine differences between groups. Linear models may be constructed to adjust for covariates and for effect modification. | March 2025 | 
| Assessment of delayed memory | RAVLT 20 minute recall accuracy scores, will be used to measure delayed memory and will be compared between groups. Distributions of relevant variables will be examined for outliers and to determine appropriate statistics for use. Chi-square, Kruskal-Wallis, and analysis of variance (ANOVA) will be used to examine differences between groups. Linear models may be constructed to adjust for covariates and for effect modification. | March 2025 | 
| Assessment of working memory | Letter-Number Sequencing subtest from the Wechsler Memory Scale III scores will be used to measure working memory and will be compared between groups. Distributions of relevant variables will be examined for outliers and to determine appropriate statistics for use. Chi-square, Kruskal-Wallis, and analysis of variance (ANOVA) will be used to examine differences between groups. Linear models may be constructed to adjust for covariates and for effect modification. | March 2025 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Assessment of cognitive flexibility using trail making tasks | Delis-Kaplan Executive Function System (DKEFS),Trail Making Task scores will be used to assess the cognitive flexibility component of executive function. Scores are derived from time to complete the task plus errors. Distributions of relevant variables will be examined for outliers and to determine appropriate statistics for use. Chi-squared, Kruskal-Wallis, and ANOVA tests will be used to examine differences between groups. Linear models may be constructed to adjust for covariates and for effect modification. | March 2025 | 
| Assessment of multitasking | DKEFS Trail Making Task scores will be used to assess the multitasking component of executive function. Scores are derived from time to complete the task, plus errors. Distributions of relevant variables will be examined for outliers and to determine appropriate statistics for use. Chi-squared, Kruskal-Wallis, and ANOVA tests will be used to examine differences between groups. Linear models may be constructed to adjust for covariates and for effect modification. | March 2025 | 
| Assessment of cognitive flexibility using color-word inference test | DKEFS Color-Word Interference Test (CWIT) scores will be used to measure the cognitive flexibility component of executive function. The CWIT is scored by time to complete plus errors. Distributions of relevant variables will be examined for outliers and to determine appropriate statistics for use. Chi-squared, Kruskal-Wallis, and ANOVA tests will be used to examine differences between groups. Linear models may be constructed to adjust for covariates and for effect modification. | March 2025 | 
| Assessment of inhibition | DKEFS CWIT scores will be used to measure the inhibition component of executive function. The CWIT is scored by time to complete plus errors. Distributions of relevant variables will be examined for outliers and to determine appropriate statistics for use. Chi-squared, Kruskal-Wallis, and ANOVA tests will be used to examine differences between groups. Linear models may be constructed to adjust for covariates and for effect modification. | March 2025 | 
| Assessment of verbal ability cognitive control | DKEFS Verbal Fluency Task will be used to assess the verbal functioning cognitive control ability component of executive function. Scores are derived from the number of unique, correct words. Distributions of relevant variables will be examined for outliers and to determine appropriate statistics for use. Chi-squared, Kruskal-Wallis, and ANOVA tests will be used to examine differences between groups. Linear models may be constructed to adjust for covariates and for effect modification. | March 2025 | 
| Assessment of psychomotor speed | The Grooved Peg Board test will be used to assess psychomotor speed. It is scored according to time for completion combined with the number of dropped pegs. Distributions of relevant variables will be examined for outliers and to determine appropriate statistics for use. Chi-squared, Kruskal-Wallis, and ANOVA tests will be used to examine differences between groups. Linear models may be constructed to adjust for covariates and for effect modification. | March 2025 | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Executive Function, Memory, Post-Bariatric Hypoglycemia