Interstitial glucose and subsequent affective and physical feeling states: A pilot study combining continuous glucose monitoring and ecological momentary assessment in adolescents

Perceived stress and associations between physical activity, sedentary time, and interstitial glucose in healthy adolescents

BACKGROUND

Less moderate to vigorous physical activity (MVPA), more sedentary time (ST), and higher perceived stress are related to type 2 diabetes mellitus (T2DM) occurrence, but observational evidence addressing the interaction of these factors is lacking in youth. This pilot study investigated momentary stress as a moderator in the acute associations of MVPA and ST with subsequent glucose in healthy adolescents.

METHODS

Participants (N=15, Mage=13.1±1.0 years, 10 girls, 5 with overweight/obesity) simultaneously wore a continuous glucose monitor (CGM), thigh-mounted accelerometer, and reported momentary stress via random ecological momentary assessments (EMA; Time T) for 7-14 days. MVPA and ST (min) were calculated for 60- and 120-minute time windows before each EMA prompt (Time T-1). Mean CGM-measured interstitial glucose (mg/dL) was calculated after each prompt (Mmin=120.0±25.4; Time T+1). Multilevel models assessed whether within-subject MVPA and ST (Time T-1) predicted mean glucose (Time T+1), with momentary stress as a moderator (Time T).

RESULTS

There were 513 time-matched EMA reports of stress, accelerometer, and CGM data. Momentary stress moderated the effects of MVPA 60 (β=-0.22, p=.001) and 120 min (β=-0.08, p=.02) before the prompt on subsequent glucose levels. When youth spent more time in MVPA than their average and when momentary stress was higher than their average, subsequent glucose was lower. Stress did not moderate associations of ST with glucose (p>.05).

CONCLUSIONS

Higher momentary stress may interact with higher MVPA to lower subsequent glucose in youth. Accelerometers, EMA, and CGMs can be integrated in future studies to further understand these associations in free-living environments.

Is your stress my stress? A standardized, randomized-controlled paradigm to study physiological stress contagion based on direct stress observation

BACKGROUND & OBJECTIVES

Existing research indicates that not only own stress leads to physiological stress reactions, but also observing stress in others. So far, a standardized paradigm to reliably induce physiological stress contagion based on direct face-to-face stress observation compared to an active placebo-stress observing control condition is lacking. Here, we tested a standardized randomized placebo-controlled experimental paradigm to investigate physiological reactivity to direct stress observation and characterized the stress contagion response of the major endocrine stress systems, including full reactivity kinetics.

METHODS

Healthy young male participants were randomly assigned to (1) undergo an adapted version of the Trier Social Stress Test ("TSST participants", n = 20), (2) observe it ("stress observers", n = 36), or (3) observe a corresponding placebo-stress control condition ("placebo-stress observers", n = 30). We repeatedly assessed heart rate, salivary alpha-amylase, salivary cortisol, and salivary aldosterone.

RESULTS

Stress observers exhibited greater physiological reactivity to stress observation as compared to placebo-stress observers to placebo-stress observation in heart rate, salivary alpha-amylase, and cortisol (p's ≤ .027), but not in aldosterone. We observed similar reactivity kinetics in TSST participants and stress observers but less pronounced in stress observers.

DISCUSSION

Extending previous literature, our findings indicate that independent of secondary effects of the observation setting, direct observation of stress in other individuals induces activation of the hypothalamus-pituitary-adrenal axis and the sympathetic-adrenal-medullary axis. Moreover, the physiological stress contagion response resembles the physiological reactivity to first-hand stress but is less pronounced. Potential implications of physiological stress contagion regarding health, cognition, or behavior, as well as modulating factors need to be further elucidated.

Glucose variability and mood in people with type 1 diabetes using ecological momentary assessment

OBJECTIVE

Mood fluctuations related to blood glucose excursions are a commonly reported source of diabetes-distress, but research is scarce. We aimed to assess the relationship between real-time glucose variability and mood in adults with type 1 diabetes (T1D) using ecological momentary assessments.

METHODS

In this prospective observational study, participants wore a masked continuous glucose monitor and received prompts on their smartphone 6 times a day to answer questions about their current mood (Profile Of Mood States (POMS)-SF (dimensions: Anxiety, Depressive symptoms, Anger, Fatigue, Vigor)) for 14 days. Mixed model analyses examined associations over time between daily Coefficient of Variation (CV) of blood glucose and mean and variability (CV) of POMS scores. Further, within-person differences in sleep and nocturnal hypoglycemia were explored.

RESULTS

18 people with T1D (10 female, mean age 44.3 years) participated. A total of 264 out of 367 days (70.2%) could be included in the analyses. No overall significant associations were found between CV of blood glucose and mean and CV of POMS scores, however, nocturnal hypoglycemia moderated the associations between CV of blood glucose and POMS scales (mean Fatigue Estimate 1.998, p < .006, mean Vigor Estimate -3.308, p < .001; CV Anger Estimate 0.731p = 0.02, CV Vigor Estimate -0.525, p = .006).

CONCLUSION

We found no overall relationship between real-time glycemic variability and mood per day. Further research into within-person differences such as sleep and nocturnal hypoglycemia is warranted.

Real-time Assessment of the Bidirectional Relationship Between Affective States and Glucose: Protocol for a 14-Day Observational Study

BACKGROUND

Glucose variability increases cardiometabolic disease risk. While many factors can influence glucose levels, postprandial glucose response is the primary driver of glucose variability. Furthermore, affect may directly and indirectly impact glucose variability through its effect on eating behavior. Continuous glucose monitors (CGMs) facilitate the real-time evaluation of blood glucose, and ecological momentary assessment (EMA) can be used to assess affect in real time. Together, data collected from these sources provide the opportunity to further understand the role of affect in glucose levels.

OBJECTIVE

This paper presents the protocol for a study that aims to (1) evaluate the feasibility and acceptability of using CGMs along with EMA in nondiabetic populations and (2) examine the bidirectional relationship between affect and glucose in nondiabetic adults with overweight or obesity using a CGM and EMA.

METHODS

Eligibility criteria for the study include participants (1) aged 18 to 65 years old, (2) with a BMI of ≥25 kg/m², (3) who are able to read and write in English, and (4) who own a smartphone. Individuals will be excluded if they (1) have type 1 or 2 diabetes or have any other condition that requires glucose monitoring, (2) are pregnant, (3) use any medications that have the potential to alter blood glucose levels or interfere with the glucose sensing process, or (4) have a diagnosed gastrointestinal condition or eating disorder. In a 14-day observational study, participants will wear a FreeStyle Libre Pro CGM sensor (Abbott) and will receive mobile phone-based EMA prompts 6 times per day (randomly within six 2-hour windows between 8 AM and 8 PM) to assess positive and negative affect. Participants will also wear a Fitbit Inspire 2 (Fitbit) to continuously monitor physical activity and sleep, which will be included as covariates in the analysis. Multilevel linear regression models will be used to evaluate the acute relationship between glucose level and affect.

RESULTS

Recruitment started in October 2022 and is expected to be completed in March 2023. We will aim to recruit 100 participants. As of December 12, 2022, a total of 39 participants have been enrolled.

CONCLUSIONS

The results of this study will further elucidate the role of affect in glucose variability. By identifying affective states that may lead to glucose excursions, our findings could inform just-in-time behavioral interventions by indicating opportunities for intervention delivery.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/45104.

Time-Varying Associations Between Device-Based and Ecological Momentary Assessment-Reported Sedentary Behaviors and the Concurrent Affective States Among Adolescents: Proof-of-Concept Study

BACKGROUND

Previous studies on affective state-sedentary behavior (SB) associations have not accounted for their potentially time-varying nature and have used inconsistent SB measurement modalities. We investigated whether the strength of the associations between affective states and SB varied as a function of the time of day and by SB measurement modality (device-measured SB vs ecological momentary assessment-reported screen-based SB) in youth.

OBJECTIVE

This study aimed to establish a proof of concept that SB-affective state associations may not be static during the day. In addition, we aimed to inform the methodology of future work, which may need to model associations as functions of the time of day and carefully consider how SB is operationalized or measured.

METHODS

A total of 15 adolescents (age: mean 13.07, SD 1.03 years; 10/15, 67% female; 6/15, 40% Hispanic; 10/15, 67% healthy weight) wore thigh-mounted activPAL accelerometers and simultaneously reported their screen-based SBs and concurrent positive and negative affective states via ecological momentary assessment for 7 to 14 days (N=636 occasions). Time-varying effect models (varying slopes) examined how each measure of SB was associated with concurrent affective states from 7 AM to 8 PM.

RESULTS

Time-varying effect model plots revealed that these associations varied in strength throughout the day. Specifically, device-based SB was related to greater concurrent negative affect only after approximately 5 PM and was unrelated to concurrent positive affect. Screen-based SB was related to greater concurrent negative affect only from 7 AM to approximately 9 AM. This was also related to greater concurrent positive affect from 7 AM to approximately 9:30 AM and from approximately 3 PM to approximately 7 PM.

CONCLUSIONS

We provide preliminary evidence to suggest that future confirmatory studies investigating the SB-affective state relationship should consider the time-varying nature of these associations and SB measurement modality. There may be critical time windows when specific types of SBs co-occur with affect, suggesting that interventions may need tailoring to the time of day and type of SB if future studies using similar methodologies can replicate our findings.

Momentary intentions and perceived behavioral control are within-person predictors of sedentary leisure time: preliminary findings from an ecological momentary assessment study in adolescents

Previous studies among adolescents conceptualize behavioral cognitions [e.g., intentions and perceived behavioral control (PBC)] as stable trait-like factors despite evidence suggesting they vary momentarily. We examined whether intentions and PBC momentarily relate to subsequent sedentary time during non-school periods. Healthy adolescents (N = 15, ages 11-15) reported their intentions and PBC regarding sedentary leisure behaviors via ecological momentary assessment (EMA) up to seven times/day for 14 days. Sedentary time in the two hours following each EMA prompt was measured by ActivPAL accelerometers. When participants reported greater sedentary intentions (within-person β = 1.1, 95% CI 0.2, 2.1, p = 0.0213) and sedentary PBC (within-person β = 1.7, 95% CI 0.6, 2.8, p = 0.0029), they accumulated greater sedentary time. This demonstrates that sedentary intentions and PBC are acutely associated with sedentary time among adolescents. Our findings highlight the potential for implementing just-in-time activity interventions among adolescents during at-risk periods within the day, characterized by deviations from one's usual intentions and PBC levels.