Feasibility and acceptability of measuring prenatal stress in daily life using smartphone-based ecological momentary assessment and wearable physiological monitors.

High levels of stress during pregnancy can have lasting effects on maternal and offspring health, which disproportionately impacts families facing financial strain, systemic racism, and other forms of social oppression. Developing ways to monitor daily life stress during pregnancy is important for reducing stress-related health disparities. We evaluated the feasibility and acceptability of using mobile health (mHealth) technology (i.e., wearable biosensors, smartphone-based ecological momentary assessment) to measure prenatal stress in daily life. Fifty pregnant women (67% receiving public assistance; 70% Black, 6% Multiracial, 24% White) completed 10 days of ambulatory assessment, in which they answered smartphone-based surveys six times a day and wore a chest-band device (movisens EcgMove4) to monitor their heart rate, heart rate variability, and activity level. Feasibility and acceptability were evaluated using behavioral meta-data and participant feedback. Findings supported the feasibility and acceptability of mHealth methods: Participants answered approximately 75% of the surveys per day and wore the device for approximately 10 hours per day. Perceived burden was low. Notably, participants with higher reported stressors and financial strain reported lower burden associated with the protocol than participants with fewer life stressors, highlighting the feasibility of mHealth technology for monitoring prenatal stress among pregnant populations living with higher levels of contextual stressors. Findings support the use of mHealth technology to measure prenatal stress in real-world, daily life settings, which shows promise for informing scalable, technology-assisted interventions that may help to reduce health disparities by enabling more accessible and comprehensive care during pregnancy.

Just-in-time adaptive ecological momentary assessment (JITA-EMA).

Interest in just-in-time adaptive interventions (JITAI) has rapidly increased in recent years. One core challenge for JITAI is the efficient and precise measurement of tailoring variables that are used to inform the timing of momentary intervention delivery. Ecological momentary assessment (EMA) is often used for this purpose, even though EMA in its traditional form was not designed specifically to facilitate momentary interventions. In this article, we introduce just-in-time adaptive EMA (JITA-EMA) as a strategy to reduce participant response burden and decrease measurement error when EMA is used as a tailoring variable in JITAI. JITA-EMA builds on computerized adaptive testing methods developed for purposes of classification (computerized classification testing, CCT), and applies them to the classification of momentary states within individuals. The goal of JITA-EMA is to administer a small and informative selection of EMA questions needed to accurately classify an individual's current state at each measurement occasion. After illustrating the basic components of JITA-EMA (adaptively choosing the initial and subsequent items to administer, adaptively stopping item administration, accommodating dynamically tailored classification cutoffs), we present two simulation studies that explored the performance of JITA-EMA, using the example of momentary fatigue states. Compared with conventional EMA item selection methods that administered a fixed set of questions at each moment, JITA-EMA yielded more accurate momentary classification with fewer questions administered. Our results suggest that JITA-EMA has the potential to enhance some approaches to mobile health interventions by facilitating efficient and precise identification of momentary states that may inform intervention tailoring.

Testing the efficacy of real-time fMRI neurofeedback for training people who smoke daily to upregulate neural responses to nondrug rewards.

Although the use of nondrug rewards (e.g., money) to facilitate smoking cessation is widespread, recent research has found that such rewards may be least effective when people who smoke cigarettes are tempted to do so. Specifically, among people who smoke, the neural response to nondrug rewards appears blunted when access to cigarettes is anticipated, and this blunting is linked to a decrease in willingness to refrain from smoking to earn a monetary incentive. Accordingly, methods to enhance the value of nondrug rewards may be theoretically and clinically important. The current proof-of-concept study tested if real-time fMRI neurofeedback training augments the ability to upregulate responses in reward-related brain areas relative to a no-feedback control condition in people who smoke. Adults (n = 44, age range = 20-44) who reported smoking >5 cigarettes per day completed the study. Those in the intervention group (n = 22, 5 females) were trained to upregulate brain responses using feedback of ongoing striatal activity (i.e., a dynamic "thermometer" that reflected ongoing changes of fMRI signal intensity in the striatum) in a single neurofeedback session with three training runs. The control group (n = 22, 5 females) underwent a nearly identical procedure but received no neurofeedback. Those who received neurofeedback training demonstrated significantly greater increases in striatal BOLD activation while attempting to think about something rewarding compared to controls, but this effect was present only during the first training run. Future neurofeedback research with those who smoke should explore how to make neurofeedback training more effective for the self-regulation of reward-related brain activities.

Mean affect and affect variability may interact to predict inflammation.

INTRODUCTION: Individuals with greater affect variability (i.e., moment-to-moment fluctuations possibly reflecting emotional dysregulation) are at risk for greater systemic inflammation, which is associated with cardiovascular disease. Some evidence suggests that affect variability is linked with poorer health indicators only among those with higher average levels of affect, particularly for positive affect (PA), and that associations may be non-linear. The present study sought to examine whether links between both PA and negative affect (NA) variability and inflammation are moderated by average level of affect. METHODS: Participants (N = 300, 50 % female, ages 21-70, 60 % non-Hispanic White, 19 % Hispanic, 15 % non-Hispanic Black) completed a lab assessment and provided a blood sample to measure systemic inflammation (i.e., TNF-α, IL-6, CRP). Affect was collected via a two-day ecological momentary assessment protocol where reports were collected about every 45-min during waking hours. Momentary affect ratings were averaged across both days (i.e., iM), separately for PA and NA, for each participant. Affect variability was calculated as the person-specific SD (i.e., iSD) of affect reports, separately for PA and NA. Linear and quadratic interactions were tested. Models included covariates for sex, race, and body mass index. RESULTS: There were significant interactions between NA iM and NA iSD predicting TNF-α (b = 6.54; p < 0.05) and between PA iM and PA iSD predicting IL-6 (b = 0.45; p < 0.05). Specifically, the association between these affect variability indicators and inflammatory markers were suggestive of a positive association among those with higher average affect but a negative association among those with lower average affect. There was no evidence of non-linear associations between affect and inflammation. DISCUSSION: Incorporating interactive effects between affect variability and average affect may be an important consideration in understanding affective-inflammatory associations.

Evaluation of Pressing Issues in Ecological Momentary Assessment.

The use of repeated, momentary, real-world assessment methods known as the Experience Sampling Method and Ecological Momentary Assessment (EMA) has been broadly embraced over the last few decades. These methods have extended our assessment reach beyond lengthy retrospective self-reports as they can capture everyday experiences in their immediate context, including affect, behavior, symptoms, and cognitions. In this review we evaluate nine conceptual, methodological, and psychometric issues about EMA with the goal of stimulating conversation and guiding future research on these matters: the extent to which participants are actually reporting momentary experiences, respondents' interpretation of momentary questions, the use of comparison standards in responding, efforts to increase the EMA reporting period beyond the moment to longer periods within a day, training of EMA study participants, concerns about selection bias of respondents, the impact of missing EMA assessments, the reliability of momentary data, and for which purposes EMA might be considered a gold standard for assessment. Resolution of these issues should have far-reaching implications for advancing the field.

Implementing text-messaging to support and enhance delivery of health behavior change interventions in low- to middle-income countries: case study of the Lifestyle Africa intervention.

The prevalence of non-communicable diseases, such as diabetes and cardiovascular disease, is rising in low- and middle-income countries (LMICs). Health behavior change (HBC) interventions such as the widely used Diabetes Prevention Program (DPP) are effective at reducing chronic disease risk, but have not been adapted for LMICs. Leveraging mobile health (mHealth) technology such as text messaging (SMS) to enhance reach and participant engagement with these interventions has great promise, yet we lack evidence-informed approaches to guide the integration of SMS specifically to support HBC interventions in LMIC contexts. To address this gap, we integrated guidance from the mHealth literature with expertise and first-hand experience to establish specific development steps for building and implementing SMS systems to support HBC programming in LMICs. Specifically, we provide real-world examples of each development step by describing our experience in designing and delivering an SMS system to support a culturally-adapted DPP designed for delivery in South Africa. We outline eight key SMS development steps, including: 1) determining if SMS is appropriate; 2) developing system architecture and programming; 3) developing theory-based messages; 4) developing SMS technology; 5) addressing international SMS delivery; 6) testing; 7) system training and technical support; and 8) cost considerations. We discuss lessons learned and extractable principles that may be of use to other mHealth and HBC researchers working in similar LMIC contexts.Trial registration Clinicaltrials.gov, NCT03342274 . Registered 10 November 2017.

Introversion and the frequency and intensity of daily uplifts and hassles.

OBJECTIVE: There is reason to believe that introversion may relate to different patterns of negative and positive experiences in everyday life ("hassles" and "uplifts"), but there is little evidence for this based on reports made in daily life as events occur. We thus extend the literature by using data from ecological momentary assessments to examine whether introversion is associated with either the frequency or intensity of hassles and uplifts. METHOD: Participants (N = 242) were community-dwelling adults (63% Black, 24% Hispanic; ages 25-65; 65% women) who completed baseline measures of personality and mental health, followed by reports of hassles and uplifts 5x/day for 14 days. We present associations between introversion and hassles/uplifts both with and without controlling for mood-related factors (neuroticism, recent symptoms of depression, and anxiety). RESULTS: Introversion was associated with reporting less frequent and less enjoyable uplifts, but not with overall hassle frequency or unpleasantness; exploratory analyses suggest associations with specific types of hassles. CONCLUSIONS: Our results expand understanding of the role of introversion in everyday experiences, suggesting an overall association between introversion and uplifts (but not hassles, broadly) in daily life. Better understanding of such connections may inform future research to determine mechanisms by which introversion relates to health.

Evaluation of an adapted version of the Diabetes Prevention Program for low- and middle-income countries: A cluster randomized trial to evaluate "Lifestyle Africa" in South Africa.

BACKGROUND: Low- and middle-income countries (LMICs) are experiencing major increases in diabetes and cardiovascular conditions linked to overweight and obesity. Lifestyle interventions such as the United States National Diabetes Prevention Program (DPP) developed in high-income countries require adaptation and cultural tailoring for LMICs. The objective of this study was to evaluate the efficacy of "Lifestyle Africa," an adapted version of the DPP tailored for an underresourced community in South Africa compared to usual care. METHODS AND FINDINGS: Participants were residents of a predominantly Xhosa-speaking urban township of Cape Town, South Africa characterized by high rates of poverty. Participants with body mass index (BMI) ≥ 25 kg/m2 who were members of existing social support groups or "clubs" receiving health services from local nongovernmental organizations (NGOs) were enrolled in a cluster randomized controlled trial that compared Lifestyle Africa (the intervention condition) to usual care (the control condition). The Lifestyle Africa intervention consisted of 17 video-based group sessions delivered by trained community health workers (CHWs). Clusters were randomized using a numbered list of the CHWs and their assigned clubs based on a computer-based random allocation scheme. CHWs, participants, and research team members could not be blinded to condition. Percentage weight loss (primary outcome), hemoglobin A1c (HbA1c), blood pressure, triglycerides, and low-density lipoprotein (LDL) cholesterol were assessed 7 to 9 months after enrollment. An individual-level intention-to-treat analysis was conducted adjusting for clustering within clubs and baseline values. Trial registration is at ClinicalTrials.gov (NCT03342274). Between February 2018 and May 2019, 782 individuals were screened, and 494 were enrolled. Participants were predominantly retired (57% were receiving a pension) and female (89%) with a mean age of 68 years. Participants from 28 clusters were allocated to Lifestyle Africa (15, n = 240) or usual care (13, n = 254). Fidelity assessments indicated that the intervention was generally delivered as intended. The modal number of sessions held across all clubs was 17, and the mean attendance of participants across all sessions was 61%. Outcome assessment was completed by 215 (90%) intervention and 223 (88%) control participants. Intent-to-treat analyses utilizing multilevel modeling included all randomized participants. Mean weight change (primary outcome) was -0.61% (95% confidence interval (CI) = -1.22, -0.01) in Lifestyle Africa and -0.44% (95% CI = -1.06, 0.18) in control with no significant difference (group difference = -0.17%; 95% CI = -1.04, 0.71; p = 0.71). However, HbA1c was significantly lower at follow-up in Lifestyle Africa compared to the usual care group (mean difference = -0.24, 95% CI = -0.39, -0.09, p = 0.001). None of the other secondary outcomes differed at follow-up: systolic blood pressure (group difference = -1.36; 95% CI = -6.92, 4.21; p = 0.63), diastolic blood pressure (group difference = -0.39; 95% CI = -3.25, 2.30; p = 0.78), LDL (group difference = -0.07; 95% CI = -0.19, 0.05; p = 0.26), triglycerides (group difference = -0.02; 95% CI = -0.20, 0.16; p = 0.80). There were no unanticipated problems and serious adverse events were rare, unrelated to the intervention, and similar across groups (11 in Lifestyle Africa versus 13 in usual care). Limitations of the study include the lack of a rigorous dietary intake measure and the high representation of older women. CONCLUSIONS: In this study, we found that Lifestyle Africa was feasible for CHWs to deliver and, although it had no effect on the primary outcome of weight loss or secondary outcomes of blood pressure or triglycerides, it had an apparent small significant effect on HbA1c. The study demonstrates the potential feasibility of CHWs to deliver a program without expert involvement by utilizing video-based sessions. The intervention may hold promise for addressing cardiovascular disease (CVD) and diabetes at scale in LMICs. TRIAL REGISTRATION: ClinicalTrials.gov NCT03342274.

Transdermal sensor features correlate with ecological momentary assessment drinking reports and predict alcohol-related consequences in young adults' natural settings.

BACKGROUND: Wearable transdermal alcohol concentration (TAC) sensors allow passive monitoring of alcohol concentration in natural settings and measurement of multiple features from drinking episodes, including peak intoxication level, speed of intoxication (absorption rate) and elimination, and duration. These passively collected features extend commonly used self-reported drink counts and may facilitate the prediction of alcohol-related consequences in natural settings, aiding risk stratification and prevention efforts. METHOD: A total of 222 young adults aged 21-29 (M age = 22.3, 64% female, 79% non-Hispanic white, 84% undergraduates) who regularly drink heavily participated in a 5-day study that included the ecological momentary assessment (EMA) of alcohol consumption (daily morning reports and participant-initiated episodic EMA sequences) and the wearing of TAC sensors (SCRAM-CAM anklets). The analytic sample contained 218 participants and 1274 days (including 554 self-reported drinking days). Five features-area under the curve (AUC), peak TAC, rise rate (rate of absorption), fall rate (rate of elimination), and duration-were extracted from TAC-positive trajectories for each drinking day. Day- and person-level associations of TAC features with drink counts (morning and episodic EMA) and alcohol-related consequences were tested using multilevel modeling. RESULTS: TAC features were strongly associated with morning drink reports (r = 0.6-0.7) but only moderately associated with episodic EMA drink counts (r = 0.3-0.5) at both day and person levels. Higher peaks, larger AUCs, faster rise rates, and faster fall rates were significantly predictive of day-level alcohol-related consequences after adjusting for both morning and episodic EMA drink counts in separate models. Person means of TAC features added little above daily scores to the prediction of alcohol-related consequences. CONCLUSIONS: These results support the utility of TAC sensors in studies of alcohol misuse among young adults in natural settings and outline the specific TAC features that contribute to the day-level prediction of alcohol-related consequences. TAC sensors provide a passive option for obtaining valid and unique information predictive of drinking risk in natural settings.

Intra-individual Associations of Perceived Stress, Affective Valence, and Affective Arousal with Momentary Cortisol in a Sample of Working Adults.

BACKGROUND: Research pairing ecological momentary assessment (EMA) methodology and ambulatory cortisol during daily life is still rare, as is careful testing of the within-person associations between stress, affect, and cortisol. Using a circumplex approach, we considered both valence and arousal components of affect. PURPOSE: To examine the within-person covariation of momentary cortisol with momentary perceived stress, affective valence, and affective arousal in everyday life. METHODS: 115 working adults (Mage = 41.2; 76% women; 76% white) completed six EMA surveys per day over 3 days. Each assessment included reports of perceived stress and affect (used to construct indicators of affective valence and arousal), followed by a saliva sample (from which cortisol was assessed). Multi-level models were used to examine the momentary associations between perceived stress, affective valence, affective arousal, and cortisol. RESULTS: Moments characterized by higher perceived stress were associated with higher cortisol (p = .036). Affective valence covaried with cortisol (p = .003) such that more positive valence was associated with lower cortisol and more negative valence with higher cortisol. Momentary affective arousal was not related to cortisol (p = .131). When all predictors were tested in the same model, only valence remained a significant predictor of cortisol (p = .047). CONCLUSION: Momentary perceived stress and affective valence, but not affective arousal, were associated with naturalistic cortisol. Cortisol was more robustly associated with affective valence than perceived stress or affective arousal. These findings extend our understanding of how moments of stress and particular characteristics of affective states (i.e., valence but not arousal) may "get under the skin" in daily life.

Relationships between daily stress responses in everyday life and nightly sleep.

Stress and sleep are related, but the nature and time course of this relation is not well understood. We explored the within-person associations of three components of emotional responses to everyday stressors, indexed by negative affect, reactivity (initial response to a stressor), recovery (persistence of the post-stressor response), and pile-up (accumulation of stress episodes), with sleep indicators. We conducted coordinated analyses of data in several studies employing ecological momentary assessments, which captured naturally occurring, self-reported stress and sleep. We defined proximal reactivity as the emotional response to the stressor moment in question compared to an immediate pre-stressor state, and distal reactivity as the emotional response to the stressor moment in question compared to a typical stressor-free state for that person. Results in two of three studies showed that people reported significantly lower sleep quality following days on which they experienced higher levels of distal reactivity to stressors. Days with greater distal reactivity also predicted significantly more difficulty falling asleep in one of two studies. There was no clear association between proximal reactivity and subsequent sleep. Associations of recovery or pile-up with subsequent sleep emerged only in single studies. Poorer sleep quality was significantly related to higher next day levels of negative affect in all three studies, but there were no consistent relations between sleep and next day stress reactivity, recovery, or pile-up. These exploratory analyses suggest that distal reactivity is associated with a heightened risk of experiencing poor sleep quality the following night, and as such the former may serve as a candidate for potential targets for the remediation of the negative effects of stress on sleep.

Mindfulness training reduces loneliness and increases social contact in a randomized controlled trial.

Loneliness and social isolation are a growing public health concern, yet there are few evidence-based interventions for mitigating these social risk factors. Accumulating evidence suggests that mindfulness interventions can improve social-relationship processes. However, the active ingredients of mindfulness training underlying these improvements are unclear. Developing mindfulness-specific skills-namely, (i) monitoring present-moment experiences with (ii) an orientation of acceptance-may change the way people perceive and relate toward others. We predicted that developing openness and acceptance toward present experiences is critical for reducing loneliness and increasing social contact and that removing acceptance-skills training from a mindfulness intervention would eliminate these benefits. In this dismantling trial, 153 community adults were randomly assigned to a 14-lesson smartphone-based intervention: (i) training in both monitoring and acceptance (Monitor+Accept), (ii) training in monitoring only (Monitor Only), or (iii) active control training. For 3 d before and after the intervention, ambulatory assessments were used to measure loneliness and social contact in daily life. Consistent with predictions, Monitor+Accept training reduced daily-life loneliness by 22% (d = 0.44, P = 0.0001) and increased social contact by two more interactions each day (d = 0.47, P = 0.001) and one more person each day (d = 0.39, P = 0.004), compared with both Monitor Only and control trainings. These findings describe a behavioral therapeutic target for improving social-relationship functioning; by fostering equanimity with feelings of loneliness and social disconnect, acceptance-skills training may allow loneliness to dissipate and encourage greater engagement with others in daily life.

A Preliminary Investigation of the Underlying Mechanism Associating Daily Sleep Continuity Disturbance and Prescription Opioid Use Among Individuals With Sickle Cell Disease.

BACKGROUND: There are emerging data indicating that sleep disturbance may be linked with an increase in opioid use. The majority of sickle cell disease (SCD) patients experience sleep disturbances, which can elevate pain severity and pain catastrophizing, both of which are important predictors of opioid consumption. PURPOSE: We conducted a preliminary investigation on the association between previous night sleep disturbance and short-acting opioid use, as well as the potential mediating roles of pain severity and pain catastrophizing. Because sex is associated with sleep disturbance, pain-related experiences, and opioid use, we also explored the potential moderating role of sex. METHODS: Participants were 45 SCD patients who were prescribed opioids. For 3 months, sleep diaries were collected immediately upon participants' awakening. Daily pain severity, pain catastrophizing, and prescription opioid use measures were collected before bedtime. RESULTS: Multilevel structural equation modeling revealed that wake time after sleep onset (WASO) during the previous night (Time 1) predicted greater short-acting opioid use during the next day (Time 2). Pain severity and pain catastrophizing measured during the next day (Time 2) also mediated the association between the two. Sex moderation analysis showed that the positive association between WASO and pain severity was largely driven by women. CONCLUSION: These findings provide some preliminary evidence as to the mechanism linking sleep continuity disturbance and opioid requirement in SCD patients. Future studies should replicate and extend these findings with clearer temporal information and employing more refined measures of sleep continuity and prescription opioid use in a larger sample.

Sex Moderates Treatment Effects of Integrated Collaborative Care for Comorbid Obesity and Depression: The RAINBOW RCT.

BACKGROUND: Sex influences health and related behaviors due to biological and psychosocial/socioeconomic factors. Assessing sex-specific responses to integrated treatment for comorbid obesity and depression could inform intervention targeting. PURPOSE: To test (a) whether sex moderates the effects of integrated collaborative care on weight and depression outcomes through 24 months and (b) whether treatment response at 6 months predicts 12 and 24 month outcomes by sex. METHODS: Secondary data analyses on weight and depression severity (SCL-20) measured over 24 months among 409 adults with obesity and depression in the Research Aimed at Improving Both Mood and Weight trial. RESULTS: Men achieved significantly greater weight reductions in intervention versus usual care than women, whereas women achieved significantly greater percentage reductions in SCL-20 than men at both 12 and 24 months. In logistic models, at 80% specificity for correctly identifying participants not achieving clinically significant long-term outcomes, women who lost <3.0% weight and men who lost <4.1% weight at 6 months had ≥84% probability of not meeting 5% weight loss at 24 months. Similarly, at 80% specificity, women who reduced SCL-20 by <39.5% and men who reduced by <53.0% at 6 months had ≥82% probability of not meeting 50% decrease in SCL-20 at 24 months. CONCLUSIONS: Sex modified the integrated treatment effects for obesity and depression. Sex-specific responses at 6 months predicted clinically significant weight loss and depression outcomes through 24 months. Based on early responses, interventions may need to be tailored to address sex-specific barriers and facilitators to achieving healthy weight and depression outcomes at later time points. CLINICAL TRIAL REGISTRATION: NCT02246413 (https://clinicaltrials.gov/ct2/show/NCT02246413).

Adaptive mHealth Intervention for Adolescent Physical Activity Promotion.

OBJECTIVE: The present nonrandomized controlled trial aimed to evaluate feasibility, acceptability, and preliminary efficacy of a tailored text message intervention for increasing adolescent physical activity, as compared with passive monitoring. METHODS: Forty adolescents (13-18 years old) received either a tailored text messaging intervention (Network Underwritten Dynamic Goals Engine [NUDGE]; N = 20), or participated in an attention-control condition (N = 20), for 20 days. Physical activity was measured for all participants via continuous accelerometry. Frequency analyses were conducted on program usage and satisfaction ratings to evaluate feasibility and acceptability, and multilevel models were used to evaluate the efficacy hypotheses. RESULTS: The vast majority of participants (90%) reported being very or mostly satisfied with the NUDGE program and rated their enjoyment as above average. The intervention group was estimated to spend an average of 20.84 more minutes per day in moderate-to-vigorous physical activity relative to the attention-control group (ß = 20.84, SE = 8.19). Exploratory analyses revealed that the intervention group also engaged in 82 fewer minutes of sedentary time per day on average, although this effect was not significant due to the large variability in sedentary time (ß = -81.98, SE = 46.86). CONCLUSIONS: The NUDGE tailored text messaging intervention was feasible, acceptable, and efficacious in increasing physical activity in this sample. Findings warrant additional evaluation of NUDGE as both a standalone physical activity intervention or as part of a multicomponent package.

Relations between social comparisons and physical activity among women in midlife with elevated risk for cardiovascular disease: an ecological momentary assessment study.

Women in midlife (ages 40-60) show decreases in physical activity (PA) that exacerbate risk for cardiovascular disease. Social comparisons (i.e., self-evaluations relative to others) are known to influence PA in other groups, but their association in this population is unknown. The present study used ecological momentary assessment to examine this relation among women in midlife with hypertension or another CVD risk condition (N = 75, MBMI = 34.0 kg/m2). Participants completed 5 surveys per day and wore tri-axial accelerometers for 10 days. PA engagement was lower after women reported more comparisons than were typical for them (7-14% reductions in PA for each additional comparison). These relations varied across days of observation and relations were positive on 34-58% of days. Findings call for careful consideration of how best to harness any potential benefits of social comparison for promoting PA in this and other groups.

Bidirectional Associations of Momentary Affect with Physical Activity and Sedentary Behaviors in Working Adults.

BACKGROUND: Affective experiences and movement-based behaviors form a system that has been shown to influence exercise adherence and mental health outcomes. Little is known about the naturalistic dynamics of the reciprocal associations in this system. PURPOSE: We examined the time intervals at which momentary affect precedes and follows movement-based behaviors in everyday life. METHODS: A community sample of working adults (n = 111) completed ecological momentary assessments (EMA) asking about current affect states (sad, happy, tired, and interested) six times a day for three consecutive days. Ratings were used to generate scores for momentary affective arousal and valence. Participants also wore an activity monitor. Total activity counts and sedentary duration in the shorter to longer time intervals (5-120 min) before or after EMA were used as indicators of movement-based behaviors. RESULTS: Multilevel modeling showed that current affective arousal predicted higher subsequent activity counts in the longer time intervals (120 min) and less subsequent sedentary behavior in the shorter to longer time intervals (5, 60, and 120 min). For the reversed sequence, neither movement-based behavior predicted subsequent momentary arousal or valence. Affective valence was unrelated to movement-based behaviors in either temporal direction. CONCLUSIONS: Some naturally occurring affective experiences (i.e., arousal) might precede, rather than follow, movement-based behaviors. Understanding affective arousal may contribute to improved management of subsequent movement-based behaviors in everyday life.

Emotional Responses to Stressors in Everyday Life Predict Long-Term Trajectories of Depressive Symptoms.

BACKGROUND: Individuals' emotional responses to stressors in everyday life are associated with long-term physical and mental health. Among many possible risk factors, the stressor-related emotional responses may play an important role in future development of depressive symptoms. PURPOSE: The current study examined how individuals' positive and negative emotional responses to everyday stressors predicted their subsequent changes in depressive symptoms over 18 months. METHODS: Using an ecological momentary assessment approach, participants (n = 176) reported stressor exposure, positive affect (PA), and negative affect (NA) five times a day for 1 week (n = 5,483 observations) and provided longitudinal reports of depressive symptoms over the subsequent 18 months. A multivariate multilevel latent growth curve model was used to directly link the fluctuations in emotions in response to momentary stressors in everyday life with the long-term trajectory of depressive symptoms. RESULTS: Adults who demonstrated a greater difference in stressor-related PA (i.e., relatively lower PA on stressor vs. nonstressor moments) reported larger increases in depressive symptoms over 18 months. Those with greater NA responses to everyday stressors (i.e., relatively higher NA on stressor vs. nonstressor moments), however, did not exhibit differential long-term changes in depressive symptoms. CONCLUSIONS: Adults showed a pattern consistent with both PA and NA responses to stressors in everyday life, but only the stressor-related changes in PA (but not in NA) predicted the growth of depressive symptoms over time. These findings highlight the important-but often overlooked-role of positive emotional responses to everyday stressors in long-term mental health.

Everyday stress components and physical activity: examining reactivity, recovery and pileup.

The experience of naturally-occurring stress in daily life has been linked with lower physical activity levels. However, most of this evidence comes from general and static reports of stress. Less is known how different temporal components of everyday stress interfere with physical activity. In a coordinated secondary analysis of data from two studies of adults, we used intensive, micro-longitudinal assessments (ecological momentary assessments, EMA) to investigate how distinct components of everyday stress, that is, reactivity to stressor events, recovery from stressor events, and pileup of stressor events and responses predict physical activity. Results showed that components of everyday stress predicted subsequent physical activity especially for indicators of stress pileup. In both studies, the accumulation of stress responses over the previous 12 h was more predictive of subsequent physical activity than current stress reactivity or recovery responses. Results are compared to the effects of general measures of perceived stress that showed an opposite pattern of results. The novel everyday stress approach used here may be fruitful for generating new insights into physical activity specifically and health behaviors in general.

Positive and Negative Affect and Salivary Markers of Inflammation Among Young Adults.

BACKGROUND: Emerging evidence suggests that higher circulating levels of inflammatory biomarkers in blood are associated with higher negative affect (NA) and lower positive affect (PA). To our knowledge, the unique associations between NA and PA in daily life and salivary biomarkers of inflammation have not been examined. This study examined these associations in young adults. METHODS: Measures of NA and PA were created from aggregated daily measures of affect (morning and evening ratings averaged across 14 days). We investigated associations between these measures and salivary C-reactive protein (CRP) and interleukin (IL)-6 in a sample of 108 young adults (60% female, mean age = 20.45 ± 1.47), a subset of whom had self-reported chronic back pain (n = 49). CRP and IL-6 were determined from saliva obtained at the end of the daily diary period. RESULTS: After covarying for age, gender, body mass index, chronic pain status, salivary flow rate, and NA, higher PA was associated with lower salivary CRP (ß = - 0.02, 95% CI (- 0.03, - 0.00) sr2 = .06, p = .01) but not IL-6; removing NA from this model did not change results. In a model with the same covariates (and PA), NA was not significantly related to CRP or IL-6. Chronic back pain status and gender did not moderate results. CONCLUSIONS: Findings suggest that higher PA may be associated with lower salivary CRP in young adults, even after accounting for NA and demographic characteristics. Findings highlight the utility of assessing emotional states in relation to salivary markers of inflammation in future biobehavioral research.