INS NYC 2024 Program

Poster	Poster Session 08 Program Schedule 02/16/2024 01:45 pm - 03:00 pm Room: Shubert Complex (Posters 1-60) Poster Session 08: Cognition \| Cognitive Reserve Variables Final Abstract #36 Gastrointestinal dysbiosis and cognition in Parkinson’s Disease Kayla Julio, The Mind Research Network, Albuquerque, United States Stephanie Nitschke, The Mind Research Network, Albuquerque, United States Sephira Ryman, The Mind Research Network, Albuquerque, United States Andrei Vakhtin, The Mind Research Networkl, Albuquerque, United States Henry Lin, New Mexico VA Health Care Stystem, Albuquerque, United States Aleksandr Birg, New Mexico VA Health Care System, Albuquerque, United States Nicholas Shaff, The Mind Research Network, Albuquerque, United States Erik Erhardt, University of New Mexico, Albuquerque, United States Yvette Matos, The Mind Research Network, Albuquerque, United States Kimberly Barnhart, The Mind Research Network, Albuquerque, United States Andrew Mayer, The Mind Research Network, Albuquerque, United States Gerson Suarez Cedeno, Nene and Jamie Koch Comprehensive Movement Disorder Center, Department of Neurology, University of New Mexico, Albuquerque, United States Amanda Deligtisch, Nene and Jamie Koch Comprehensive Movement Disorder Center, Department of Neurology, University of New Mexico, Albuquerque, United States Sarah Pirio Richardson, Nene and Jamie Koch Comprehensive Movement Disorder Center, Department of Neurology, University of New Mexico, Albuquerque, United States Category: Movement and Movement Disorders Keyword 1: Parkinson's disease Keyword 2: neuropsychological assessment Keyword 3: cognitive functioning Objective: Gastrointestinal dysfunction occurs early in the course of PD, with evidence that it develops up to 20 years prior to a diagnosis. This has led to increased interest in how a perturbed gut microbiome (dysbiosis) may contribute to disease initiation or progression in PD. PD patients exhibit elevated rates of small intestinal bacterial overgrowth (SIBO), a specific type of dysbiosis that causes malabsorption, which is clinically detected using a lactulose breath test to quantify H₂ and/or CH₄in exhaled breath following the ingestion of lactulose. Recent evidence suggests a bloom in sulfate-reducing bacteria (SRB) may be particularly important to PD disease pathogenesis, which can also be detected via exhaled H₂S during the lactulose breath test, though it has never been evaluated in PD. Participants and Methods: 17 PD and 17 matched HC underwent a comprehensive neuropsychological evaluation, motor assessments, and a lactulose breath testing that included H₂, CH₄, and H₂S measurements. SIBO positive results were determined based on a methane value ≥ 10ppm over baseline over three hours and a hydrogen value ≥ 20ppm over baseline within 90 minutes. H₂S positivity was determined as any value greater than baseline. Mean and maximum H₂, CH₄ and H₂S levels were calculated for each participant. Chi-squared tests evaluated whether PD patients exhibited higher rates of SIBO or H₂S positivity relative to HC. Bootstrap analyses were used to evaluate whether PD patients exhibited increased mean and max H₂, CH₄ and H₂S levels relative to HC accounting for age and sex. Finally, Spearman correlation analyses were used to evaluate the associations between H₂, CH₄ and H₂S levels and clinical outcomes (age of onset and cognitive domain scores). Results: PD patients reported significantly more gastrointestinal symptoms relative to HC, including: more severe frequency and levels of current constipation (p < 0.001), lifetime frequency of stools (p = 0.048), and severity of stool strain (p = 0.006). PD and HC groups each had elevated rates of SIBO (SIBO Positive: 70.59% PD; 70.59% HC). 62.5% of the PD patients exhibited positive H₂S, whereas only 29.41% of the HC exhibited positive H₂S, though did not significantly differ based on chi-squared tests (p = 0.12) and group differences in the mean (p = 0.12) and max H₂S (p = 0.16) were not significantly different. However, mean and max H₂S were inversely associated with both age of first PD symptom (mean: rho = -0.36, p = 0.03; max: rho = -0.36, p = 0.03) and visuospatial functioning (mean: rho = -0.39, p = 0.03; max: rho = -0.40, p = 0.02). Conclusions: Our results highlight elevated gastrointestinal symptoms in PD, despite identical high rates of SIBO. A bloom in SRB may also contribute to earlier disease onset and worse visuospatial functioning. Future work in larger cohorts is necessary to further understand if a bloom in SRB is present early in the disease course and if it progresses with cognitive symptoms.

Poster

02/16/2024
01:45 pm - 03:00 pm
Room: Shubert Complex (Posters 1-60)

Poster Session 08: Cognition | Cognitive Reserve Variables

Final Abstract #36

Gastrointestinal dysbiosis and cognition in Parkinson’s Disease

Kayla Julio, The Mind Research Network, Albuquerque, United States
Stephanie Nitschke, The Mind Research Network, Albuquerque, United States
Sephira Ryman, The Mind Research Network, Albuquerque, United States
Andrei Vakhtin, The Mind Research Networkl, Albuquerque, United States
Henry Lin, New Mexico VA Health Care Stystem, Albuquerque, United States
Aleksandr Birg, New Mexico VA Health Care System, Albuquerque, United States
Nicholas Shaff, The Mind Research Network, Albuquerque, United States
Erik Erhardt, University of New Mexico, Albuquerque, United States
Yvette Matos, The Mind Research Network, Albuquerque, United States
Kimberly Barnhart, The Mind Research Network, Albuquerque, United States
Andrew Mayer, The Mind Research Network, Albuquerque, United States
Gerson Suarez Cedeno, Nene and Jamie Koch Comprehensive Movement Disorder Center, Department of Neurology, University of New Mexico, Albuquerque, United States
Amanda Deligtisch, Nene and Jamie Koch Comprehensive Movement Disorder Center, Department of Neurology, University of New Mexico, Albuquerque, United States
Sarah Pirio Richardson, Nene and Jamie Koch Comprehensive Movement Disorder Center, Department of Neurology, University of New Mexico, Albuquerque, United States

Category: Movement and Movement Disorders

Keyword 1: Parkinson's disease
Keyword 2: neuropsychological assessment
Keyword 3: cognitive functioning

Objective:

Gastrointestinal dysfunction occurs early in the course of PD, with evidence that it develops up to 20 years prior to a diagnosis. This has led to increased interest in how a perturbed gut microbiome (dysbiosis) may contribute to disease initiation or progression in PD. PD patients exhibit elevated rates of small intestinal bacterial overgrowth (SIBO), a specific type of dysbiosis that causes malabsorption, which is clinically detected using a lactulose breath test to quantify H₂ and/or CH₄in exhaled breath following the ingestion of lactulose. Recent evidence suggests a bloom in sulfate-reducing bacteria (SRB) may be particularly important to PD disease pathogenesis, which can also be detected via exhaled H₂S during the lactulose breath test, though it has never been evaluated in PD.

Participants and Methods:

17 PD and 17 matched HC underwent a comprehensive neuropsychological evaluation, motor assessments, and a lactulose breath testing that included H₂, CH₄, and H₂S measurements. SIBO positive results were determined based on a methane value ≥ 10ppm over baseline over three hours and a hydrogen value ≥ 20ppm over baseline within 90 minutes. H₂S positivity was determined as any value greater than baseline. Mean and maximum H₂, CH₄ and H₂S levels were calculated for each participant. Chi-squared tests evaluated whether PD patients exhibited higher rates of SIBO or H₂S positivity relative to HC. Bootstrap analyses were used to evaluate whether PD patients exhibited increased mean and max H₂, CH₄ and H₂S levels relative to HC accounting for age and sex. Finally, Spearman correlation analyses were used to evaluate the associations between H₂, CH₄ and H₂S levels and clinical outcomes (age of onset and cognitive domain scores).

Results:

PD patients reported significantly more gastrointestinal symptoms relative to HC, including: more severe frequency and levels of current constipation (p < 0.001), lifetime frequency of stools (p = 0.048), and severity of stool strain (p = 0.006). PD and HC groups each had elevated rates of SIBO (SIBO Positive: 70.59% PD; 70.59% HC). 62.5% of the PD patients exhibited positive H₂S, whereas only 29.41% of the HC exhibited positive H₂S, though did not significantly differ based on chi-squared tests (p = 0.12) and group differences in the mean (p = 0.12) and max H₂S (p = 0.16) were not significantly different. However, mean and max H₂S were inversely associated with both age of first PD symptom (mean: rho = -0.36, p = 0.03; max: rho = -0.36, p = 0.03) and visuospatial functioning (mean: rho = -0.39, p = 0.03; max: rho = -0.40, p = 0.02).

Conclusions:

Our results highlight elevated gastrointestinal symptoms in PD, despite identical high rates of SIBO. A bloom in SRB may also contribute to earlier disease onset and worse visuospatial functioning. Future work in larger cohorts is necessary to further understand if a bloom in SRB is present early in the disease course and if it progresses with cognitive symptoms.