Emotion-Diet Interactions in Pregnancy

Study Overview
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Brief Summary
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This study will investigate how maternal emotional state following a controlled stress exposure in pregnancy influences blood glucose and insulin levels after eating a standardized meal, and whether the effects of emotional state on blood glucose and insulin is different after eating a healthy meal (low GI) compared to a less healthy meal (high GI).

Detailed Description
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Maternal glucose-insulin homeostasis in pregnancy represents one of the most important physiological processes for maternal and child health outcomes. Although maternal diet is a key regulator of this process, its effects vary widely across individuals. Maternal stress could represent a moderator of considerable importance in this regard, yet little is known about the effects of stress on glycemic control in pregnancy and whether the effects of stress may vary as a function of diet quality. This project will investigate the effects of acute psychosocial stress exposure on the postprandial metabolic response to a meal of varying glycemic index (GI) among women with overweight/obesity in mid-pregnancy.

Official Title
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Postprandial Response to Emotion-Diet Interactions in Pregnancy

Conditions
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Pregnancy Related, Stress, Psychological, Glucose Intolerance During Pregnancy, Emotional Stress, Postprandial Hyperglycemia, Insulin Sensitivity/Resistance

Intervention / Treatment
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* Behavioral: Psychosocial stress
* Behavioral: Control non-stress


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: English and/or Spanish speaking 18-22 week's gestation Pre-pregnancy BMI 25.0-39.9 kg/m2 Singleton, intrauterine pregnancy Non-smoker Non-diabetic and normal result on a random peripheral blood glucose test at the screening visit (<200 mg/dl) Exclusion Criteria: Non-fluency in English or Spanish BMI <25.0 or ≥40.0 kg/m2 >22 week's gestation multiple pregnancy current smoker present/prior obstetric conditions (preeclampsia, infections, placental abnormalities, uterine anomalies, congenital malformations, fetal chromosomal abnormalities) presence of any conditions that may dysregulate neuroendocrine, metabolic or cardiovascular function, such as diabetes, hepatic, renal, or autoimmune disorders current psychiatric disorders or undergoing treatment/taking psychiatric medications use of systemic/frequent corticosteroids or thyroid, lipid-lowering or anti-diabetic medications gestational diabetes mellitus or raised glucose result detected on the screening visit unwilling to eat the standard breakfast meal at each laboratory visit

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 40 Years

Sexes Eligible for Study
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Female

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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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Crossover Assignment
Interventional Model Description: Participants will be first randomized in a parallel design to meal type (low vs high GI). Within the meal arms, participants will be randomized in a cross-over design to undergo the lab-based stress and non-stress tasks.
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Psychosocial stress<br>Participants will complete the Trier Social Stress Test (TSST) immediately following consumption of their assigned meal type (low or high GI). | Behavioral: Psychosocial stress<br>* The TSST is a 15 minute standardized lab-based challenge task that involves speech preparation, speech delivery while being evaluated by strangers and video taped, and complex mental arithmetic with critiques if errors are made.<br>|
| Active Comparator: Control non-stress<br>Participants will complete a non-stress relaxed task immediately following consumption of their assigned meal type (low or high GI). | Behavioral: Control non-stress<br>* Participants will have a relaxed 15 minute conversation with a familiar research team member.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Postprandial glycemic response | Intra-individual glycemic response (area-under-the-curve of glucose) to the standardized meal following exposure to either the psychosocial stress (TSST) or non-stress (control) task | 2 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Postprandial lipid response | Intra-individual lipid response (area-under-the-curve of triglycerides and free fatty acids) to the standardized meal following exposure to either the psychosocial stress (TSST) or non-stress (control) task | 2 weeks | 
| Postprandial inflammatory response | Intra-individual lipid response (area-under-the-curve of inflammatory cytokines) to the standardized meal following exposure to either the psychosocial stress (TSST) or non-stress (control) task | 2 weeks | 
| Postprandial metabolic response to stress by meal type | Inter-individual difference in the glycemic/lipid/inflammatory AUC in response to the TSST between participants consuming the low GI compared to the high GI meal type | 3 hours |