Cognitive and Biological Responses in Stress

Anxiety Clinical Trial

Official title:

Pilot Study Aimed to Determine the Optimal Design for the UCLA/Danone Probiotic Intervention Study Related to Stress

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT05026333
• Other study ID #: IRB # 20-001921
• Status: Completed
• Phase: N/A
• Start date: June 25, 2021
• Est. completion date: July 15, 2022

Study information

• Verified date: October 2022
• Source: University of California, Los Angeles
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

The goal of this pilot part of the study (Step 1) is to identify the optimal population of high and low anxiety and stress individuals who will differentially respond to a laboratory stress task as measured by changes in subjective stress response (affect), cognition, attention, and biological measures (autonomic and metabolite responses). Based on experience with different study populations, the investigator's believe that a healthy, homogenous population (Caucasian, women, premenopausal) with higher levels of state anxiety and perceived stress, and with greater responsiveness to laboratory stress tasks (which can also be used in the probiotic intervention study in Step 2) will provide the highest likelihood of identifying the underlying central mechanisms of stress responsiveness in Step 1 and then for the probiotic intervention in Step 2. For this pilot study, the investigator's will look at baseline measures to determine differences in responses to four subjective (affect/cognition/attention) stress tasks (primary endpoints) and biological (secondary endpoints) measures in a high stress group and a low stress group. If for Step 1 of the study, the investigator's are able to verify the stratification of the participants into high and low stress groups based on questionnaire data and show differences between participants with high and low perceived stress in psychological characteristics, lab stress tasks and potentially in biological responses, this will help to determine the optimal cut off values, and the optimal stress tasks to be conducted in the planned probiotic intervention study of Step 2.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 100
• Est. completion date: July 15, 2022
• Est. primary completion date: July 15, 2022
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Female
• Age group: 18 Years to 45 Years

Eligibility

Inclusion Criteria:

• Caucasian
• Female
• 18-45 years of age
• For the high perceived stress group: a PSS score of 15 or higher and a STAI-S of 39 or higher
• For the low perceived stress group: a PSS score of 8 or lower and a STAI-S score of 24 or lower

Exclusion Criteria:

• Any ongoing major medical, psychological, or psychiatric conditions and recent changes (3mo) in the use of psychoactive medications or other medications that interfere with the measured outcomes.
• Medical conditions such as current neurological, cardiovascular, hepatic, renal, autoimmune diseases, diabetes, or cancer. This includes having a current or past within 1 year diagnosis of GI disorders, including but not limited to IBS, IBD, Celiac, or other nutritional deficiency/disease, current eating disorder, or past weight loss surgery.
• Psychological conditions such as anxiety and depression (I.e., without history of Diagnostic and Statistical Manual (DSM-4) psychiatric diagnosis.
• Prior/Concomitant Therapy (e.g., Recent changes in the use of psychoactive medications or other medications that interfere with the measured outcomes, as determined by the PI).
• Subject involved in any other clinical study within the preceding month or in the exclusion period after another clinical study.
• Positive test for COVID-19 infection in the past month or if presenting symptoms of COVID-19 infection in the past 2 weeks.

Diet:

• Participant who changes her dietary habits within the preceding 4 weeks.
• Participants on probiotics will be asked to wait 1 month before enrollment in the study.
• Participant with an eating disorder.
• Participant with special medicated diet (e.g., for obesity, anorexia, metabolic pathology).
• Participant under artificial nutrition in the last 1 month.
• Participant planning to modify her dietary habits during the course of the study.

Other Exclusions:

• Pregnant women or women planning to become pregnant during the study; breast-feeding women based on the interview at screen (Visit 1) and the urine test on day of stress test (Visit 2).
• Smoker with a moderate to high level of dependence to nicotine (e.g., more than 1/2 a pack of cigarettes a day).
• Participant consuming regularly more than 3 units of alcohol per day (1 unit = 10mL or 8g).
• Participants not able to answer questionnaires by writing, whatever the reason.
• Participant with loos of liberty, by administrative or judicial decision.
• Participant who is major but with a legal guardian.
• Participant on antibiotics will be asked to wait 3 months before enrollment in the study.

Medications not Authorized:

• Opiates/Narcotics
• Chronic/Daily use of analgesics
• Anti-seizure meds
• Antidepressants (5HT3's / Tricyclics etc.) are allowed as long as it's been a stable dose for 3 months
• Medications for ADD/ADHD (I.e., Adderall)
• Any medication for appetite suppression
• Chronic use of laxative/antidiarrheals/medications affecting GI motility
• Insulin
• Bile acid sequestrants
• Use of centrally acting medications that will interfere with CNS testing

Related Conditions & MeSH terms

• Anxiety
• Stress, Psychological

Intervention

Other:
• Cognitive Stress Testing
Cognitive and stress study with no product intervention and noninvasive. The high stress/anxiety group will be compared to the low stress/anxiety group in terms of changes from baseline to after the cognitive and stress tests (i.e., 4 laboratory tasks) and metabolite measures.

Locations

Country	Name	City	State
United States	University of California, Los Angeles	Los Angeles	California

Sponsors (2)

Lead Sponsor	Collaborator
University of California, Los Angeles	Danone Nutricia Research

Country where clinical trial is conducted

United States, 

References & Publications (62)

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* Note: There are 62 references in all — Click here to view all references

Outcome

Type	Measure	Description	Time frame	Safety issue
Other	Changes in Stress-Related Plasma Metabolite Concentrations as measured via a blood sample and processed by Ixcela for targeted stress-related metabolites.	Between and within group differences in pre- and post- laboratory stress tasks in targeted stress-related metabolite concentrations assessed with the Ixcela Panel and analyzed using a Welch's two-sample t-test to identify overall metabolite changes. Extensive literature details the role of metabolites in modulation of the brain, and widespread effects on excitatory neurotransmission and neuroinflammation. (Metabolites Targeted will include the following pathways: Tryptophan, Purine, Serotonin, Kynurenine, Hypoxanthine, Xanthosine, Xanthine, Guanosine, Guanine, Uric Acid, Methionine, 4-Hydroxy 3-Methoxy Phenylacetic Acid, DL 4-Hydroxy, 3-Methoxy Mandelic Acid, Methoxy Hydroxyphenyl, Glycol, 4HPLA, 2HPAC, 4HPAC).	Pre and Post laboratory testing during the in-clinic visit lasting 2-4 hours.
Primary	Differences in Subjective Stress Response	Between group differences in pre-and post- of the "overall" negative and positive affect subscale scores from the Positive Affect and Negative Affect Scale (PANAS) administered at baseline immediately before and after the 4 brief and well validated laboratory stress tasks. PANAS scores can range from 10-50 for both the positive and negative affect, with the lower scores representing lower levels of positive/negative affect, and higher scores representing higher levels of positive/negative affect.	Pre and Post laboratory testing during the in-clinic visit lasting 2-4 hours.
Secondary	Differences in Attention/Executive Function	Between and within group differences on the time it takes to complete the Color Stroop attention/executive function lab stress task.	Throughout the Color Stroop laboratory test at the in-clinic visit lasting approximately 30 minutes.
Secondary	Differences in Emotional Arousal System	Between and within group differences in valence and emotional arousal ratings during the IAPS task.	Throughout the IAPS laboratory test during the in-clinic visit lasting approximately 30 minutes.
Secondary	Differences in Subjective Stress Response	Between and within group differences on the negative affect subscale from the Brief Positive Affect and Negative Affect Scale (PANAS) before and after the arithmetic task. PANAS scores can range from 10-50 for both the positive and negative affect, with the lower scores representing lower levels of positive/negative affect, and higher scores representing higher levels of positive/negative affect.	Pre and Post the arithmetic stress task during the in-clinic visit lasting approximately 30 minutes.
Secondary	Changes in Autonomic Measures - Heart Rate Variability	Between and within group differences in overall average change in heart rate variability pre and post each laboratory stress task.	Throughout each laboratory test during the in-clinic visit lasting 2-4 hours.
Secondary	Differences in Attention/Executive Function	Between and within group differences on the time it takes to complete the Trails A and B attention/executive function lab stress task.	Throughout the Trails A & B laboratory tests at the in-clinic visit lasting approximately 30 minutes.
Secondary	Changes in Autonomic Measures - diastolic and systolic blood pressure	Between and within group differences in overall average change in both diastolic and systolic blood pressure pre and post each laboratory stress task.	Throughout each laboratory test during the in-clinic visit lasting 2-4 hours.
Secondary	Changes in Autonomic Measures - Skin Conductance	Between and within group differences in overall average change in skin conductance pre and post each laboratory stress task.	Throughout each laboratory test during the in-clinic visit lasting 2-4 hours.