Remote dried blood spot collection for inflammatory markers in older adults is feasible, reliable, and valid.

Dried blood spots (DBS) provide a minimally invasive method to assess inflammatory markers and can be collected remotely at-home or in-person in the lab. However, there is a lack of methodological information comparing these different collection methods and in older adults. We investigated the feasibility (including adherence, yield, quality, and participant preferences) and measurement properties (reliability, validity) of remotely collected DBS inflammatory markers in older adults. Participants (N = 167, mean age = 72, range: 60-96 years) collected their own DBS (finger prick on filter paper) during three remote interviews over âˆ¼ 6 months. Within 4-5 days on average of their last remote interview, a subset of 41 participants also attended an in-person lab visit that included a researcher-collected DBS sample, venous blood draw, and survey to assess participant preferences of DBS collection. DBS and venous blood were assayed for CRP, IL-6, and TNF-α. Adherence: 98% of expected DBS samples (493 out of 501) were completed and mailed back to the lab. Yield: 97% of DBS samples were sufficient for all assays. Quality: On average, 0.80 fewer optimal spots (60uL of blood that filled the entire circle) were obtained remotely vs. in-person (p = 0.013), but the number of useable or better spots (at least 30-40uL of blood) did not differ (p = 0.89). Preference: A slight majority of participants (54%) preferred in-person DBS collection. Reliability: DBS test-retest reliabilities were good: CRP (ICC = 0.74), IL-6 (ICC = 0.76), and TNF-α (ICC = 0.70). Validity: Inflammatory levels from DBS correlated strongly with levels from venous blood (r = 0.60-0.99) and correlated as expected with sociodemographic and physical health and function variables. Older adults can remotely collect their own DBS to acquire reliable and valid inflammatory data. Remote DBS collection is highly feasible and may allow for inflammatory markers to be assessed in larger, more representative samples than are possible with lab- or clinic-based research designs.

Lifespan socioeconomic context is associated with cytomegalovirus and late-differentiated CD8+ T and NK cells: Initial results in older adults.

OBJECTIVE: Lower socioeconomic status (SES) can accelerate immune aging; however, it is unknown whether and how lifespan socioeconomic context (SEC) -the relative wealth and quality of the communities an individual lives in across their lifespan- impacts immune aging. We examined the effects of childhood and adulthood SEC on late-differentiated immune cells and investigated the mediating and moderating role of cytomegalovirus (CMV), a key driver of immune aging. METHODS: Adults 60 years and older (N = 109) reported their addresses from birth to age 60, which were coded for county-level employment, education, and income to construct a latent SEC variable, averaged across ages 0-18 (childhood SEC) and 19-60 (adulthood SEC). Blood was drawn semiannually over 5 years for CMV serostatus and flow cytometry estimates of late-differentiated CD8+ T and natural killer (NK) cells. Models were adjusted for chronological age, time, gender, and individual SES (current income and education). RESULTS: Lower childhood SEC was associated with higher percentages of late-differentiated CD8+ T and NK cells via CMV seropositivity (indirect effects ps .015-.028). Additionally, an interaction between CMV serostatus and SEC on CD8+ T cell aging (p = .049) demonstrated that adulthood SEC was negatively associated with immune aging among CMV- but not CMV+ adults. CONCLUSIONS: Beyond current SES, socioeconomic context related to immune aging in distinct patterns by lifespan phase. Lower childhood SEC importantly may influence who acquires CMV, which in turn, predicts higher levels of immune aging, whereas higher adulthood SEC was protective against immune aging among CMV- older adults. These initial results need to be explored in larger samples.

Life stressors and immune aging: Protective effects of cognitive reappraisal.

Stressful life events may accelerate aspects of immune aging, but habitual use of an adaptive emotion regulation strategy, cognitive reappraisal, may attenuate these effects. This study examined whether cognitive reappraisal moderates the associations between life stressor frequency and stressor desirability on aspects of immune aging, including late-differentiated CD8+ T and natural killer (NK) cells and inflammatory markers (IL-6, TNF-α, and CRP), both between and within people in a longitudinal sample of 149 older adults (mean age = 77.8, range: 64-92 years). Participants reported stressful life events, use of cognitive reappraisal, and provided blood semiannually for up to 5 years to assess aspects of immune aging. Multilevel models, adjusted for demographic and health covariates, tested the between-person (stable, trait-like differences) and within-person associations (dynamic fluctuations) among life stressors and reappraisal on immune aging. Experiencing more frequent life stressors than usual was associated with higher levels of late-differentiated NK cells within person, but this effect was accounted for by experiencing health-related stressors. Unexpectedly, experiencing more frequent and less desirable stressors were associated with lower average levels of TNF-α. As expected, reappraisal moderated the associations between life stressors and late-differentiated NK cells between people and IL-6 within people. Specifically, older adults who experienced less desirable stressors but also used more reappraisal had significantly lower proportions of late-differentiated NK cells on average and lower levels of IL-6 within-person. These results suggest cognitive reappraisal may play a protective role in attenuating the effects of stressful life events on aspects of innate immune aging in older adults.

Cytomegalovirus and Toxoplasma Gondii Serostatus Prospectively Correlated With Problems in Self-Regulation but not Executive Function Among Older Adults.

OBJECTIVE: Cytomegalovirus (CMV) and Toxoplasma gondii are organisms that may infect the brain and have cognitive and behavioral consequences. We hypothesized that these latent infections would be prospectively associated with poorer cognition and more problems in self-regulation among older adults. METHODS: Older adults (n = 138, mean age = 75.5 years, 59% women) had CMV and T. gondii serostatus tested, crystallized intelligence estimated (North American Adult Reading Test), and executive function (EF; e.g., Trail Making Test) and self-regulation (Behavior Regulation Inventory of Executive Function-Adult) assessed in visits occurring every 6 months (mean visits = 16). RESULTS: CMV+ people (79%) had significantly poorer self-regulation versus CMV- people (21%; behavioral regulation: γ = 0.108, 95% confidence interval [CI] = 0.009-0.206; metacognition: γ = 0.117, 95% CI = 0.005-0.229), but not intelligence or EF. T. gondii+ people (24%) were not significantly different from T. gondii- people (76%) on any outcome. However, T. gondii+ men had better self-regulation versus T. gondii- men, and the opposite was true of women (behavioral regulation interaction: γ = 0.267, 95% CI = 0.093-0.441). CONCLUSIONS: CMV latent infection was associated with more problems in self-regulation, and the magnitude of this difference was clinically significant. T. gondii latent infection was associated with more problems, but only for women. Latent infection might associate with self-regulation but not EF because of factors influencing self-regulation but not neuropsychological test performance, such as values and emotion. Efforts to link latent infection with EFs might, in the future, include the application of those functions to self-regulation in daily life.

Daily Stressors, Emotion Dynamics, and Inflammation in the MIDUS Cohort.

BACKGROUND: The current study (1) examined links between daily stressors and inflammation and (2) tested whether negative emotion dynamics (emotional variability) is one pathway through which stressors are linked to inflammation. METHOD: A cross-sectional sample of 986 adults (aged 35-86 years, 57% female) from MIDUS reported daily stressor frequency and severity and negative emotions on 8 consecutive nights. Negative emotion variability (intraindividual standard deviation), controlling for overall mean level (intraindividual mean), was the focus of the current study. Interleukin-6 (IL-6) and C-reactive protein (CRP) were assayed from blood drawn at a clinic visit. Regression models adjusted for demographics, health factors, and the time between assessments. RESULTS: More severe daily stressors were associated with higher CRP, but this effect was accounted for by covariates. More frequent daily stressors were associated with lower IL-6 and CRP. In follow-up analyses, significant interactions between stressor severity and frequency suggested that participants with lower stressor severity and higher stressor frequency had the lowest levels of IL-6 and CRP, whereas those with higher stressor severity had the highest levels of IL-6 and CRP, regardless of frequency. Daily stressor frequency and severity were positively associated with negative emotion variability, but variability was not linearly associated with inflammation and did not operate as a mediator. CONCLUSION: Among midlife and older adults, daily stressor frequency and severity may interact and synergistically associate with inflammatory markers, potentially due to these adults being advantaged in other ways related to lower inflammation, or in a pattern aligning with hormetic stress, where frequent but manageable stressors may yield physiological benefits, or both. Negative emotion variability does not operate as a mediator. Additional work is needed to reliably measure and test other emotion dynamic metrics that may contribute to inflammation.

Perceived stress, cytomegalovirus titers, and late-differentiated T and NK cells: Between-, within-person associations in a longitudinal study of older adults.

Cytomegalovirus (CMV) and psychological stress are implicated as drivers of immunological aging. It is unknown, however, whether associations among CMV titers, stress, and immune aging are more stable or dynamic over time. The present investigation tested the between-person (stable differences) and within-person (dynamic fluctuations) associations of CMV titers and perceived stress on late-differentiated T and natural killer (NK) peripheral blood cells in a longitudinal study of older adults aged 64-92 years (N = 149). Participants reported stress levels and provided blood biannually for 2.5 years (up to 5 waves per person) to assess CMV IgG titers and composites of late-differentiated CD8 T cells (CD28- and CD57 + subsets) and CD56dim NK cells (CD57+, NKG2C+, and FcεRIγ- subsets). In multilevel models that controlled for demographic variables, higher CMV titers were associated with higher proportions and counts of aged T and NK cells between people and lower counts of aged T cells within people. Perceived stress was associated with higher counts of aged T cells between people, but was not associated with aged NK cells. A significant interaction between stress and CMV titers on T cells between people indicated that older adults with lower stress levels and lower CMV titers had the lowest proportions of late-differentiated T cells, whereas those with higher stress levels had high proportions, regardless of CMV control. Our results provide evidence for longer-term, between-person associations among CMV titers, stress, and immunological aging, rather than dynamic within-person associations. We propose that targeting factors that promote low, stable perceived stress in older adults may retard T cell differentiation and ultimately support healthy aging.

Intelligence and Interleukin-6 in Older Adults: The Role of Repetitive Thought.

OBJECTIVE: Higher intelligence quotient (IQ) correlates with lower systemic inflammation, consistent with an association between lower IQ and disease risk. The present study examined the role of repetitive thought (RT) in the relationship between IQ and interleukin (IL)-6. RT is thinking attentively, repeatedly, and frequently about oneself and one's world and is characterized by valence (positive-negative), purpose (searching-solving), and total quantity (much-little). METHODS: Estimated IQ and RT dimension scores were assessed at baseline in a sample of older adults (N = 120, mean age = 74 years), who thereafter had blood drawn up to 10 times semiannually (n = 799). Models were adjusted for body mass index, chronological age, and statin medication. RESULTS: Higher IQ was associated with lower IL-6 (γ = -0.225, SE = 0.111, p = .045). Of the RT dimensions, only more total RT predicted lower IL-6 (γ = -0.037, SE = 0.011, p = .001), an effect that was not moderated by valence or purpose. More total RT accounted for part of the effect of IQ on IL-6 (indirect effect = -0.06 [confidence interval = -0.14 to -0.002]). There was also a significant interaction between IQ and total RT (F(1,119) = 6.97, p = .009), in which more total RT was more strongly associated with lower IL-6 for people with lower IQ. CONCLUSIONS: Although some forms of RT such as worry may have negative health correlates for older adults, engaging in RT per se can be healthy insofar as it also encompasses planning, processing, and coping. Older adults with higher IQ were more likely to engage in RT, but those with average IQ benefitted the most with regard to a marker of systemic inflammation.

Cytomegalovirus serostatus, inflammation, and antibody response to influenza vaccination in older adults: The moderating effect of beta blockade.

Cytomegalovirus (CMV) has been implicated as a factor in immunosenescence, including poor antibody response to vaccination and higher immune activation and inflammation. Some people may be more or less vulnerable to the negative effects of CMV. The present investigation tested the effects of beta-blocker use and chronological age on the associations between CMV and immunity in adults aged 60-91 (N=98; 69% CMV seropositive) who were administered the trivalent influenza vaccine for up to 5years. Peak antibody response, corrected for baseline, and spring (persistent) antibody response, corrected for peak, were assessed, as well as beta-2 microglobulin (ß2µ) and interleukin-6 (IL-6). In multi-level models with years at Level 1 and people at Level 2, CMV serostatus did not predict peak antibody response, but there was a 3-way interaction between CMV serostatus, age, and beta-blockers. Age was negatively associated with peak antibody, but only among adults who were CMV seropositive and taking beta-blockers. CMV seronegative adults who were not taking beta-blockers had the highest antibody persistence. CMV serostatus was not associated with ß2µ or IL-6. Results suggest that CMV+ serostatus may negatively compromise antibody response to a greater degree than inflammatory markers in older adults. Furthermore, older adults who take beta-blockers may be more vulnerable to negative effects of age and CMV on peak antibody response, perhaps by virtue of their underlying health condition.

Emotional acceptance, inflammation, and sickness symptoms across the first two years following breast cancer diagnosis.

PURPOSE: Breast cancer diagnosis and treatment are associated with increased inflammatory activity, which can induce sickness symptoms. We examined whether emotional acceptance moderates the association between proinflammatory cytokines and self-reported sickness symptoms in women recently diagnosed with breast cancer. METHODS: Women (N=136) diagnosed with stage 0-III breast cancer within the previous 6months provided plasma samples and completed the FACT: Physical Well-Being Scale, as well as the Acceptance of Emotion Scale every 3months for 2years. At each time point, we quantified interleukin (IL)-6, IL-8, IL-10, and tumor necrosis factor (TNF)-α using a high sensitivity multiplex assay. RESULTS: Higher within-subject mean TNF-α across all time-points predicted higher mean sickness symptoms. At individual time-points, higher IL-6 and IL-8 levels were associated with higher sickness symptoms. Mean emotional acceptance across all time-points moderated the relationship between mean IL-8 and sickness symptoms, with sickness symptoms remaining persistently high in women with low emotional acceptance even when IL-8 levels were low. At individual time-points, emotional acceptance positively moderated the correlations of IL-8 and TNF-α with sickness symptoms, such that the associations between higher levels of these proinflammatory cytokines and higher sickness symptoms were attenuated when emotional acceptance was high. CONCLUSION: Emotional acceptance was shown for the first time to moderate the associations of cytokines with sickness symptoms in breast cancer patients over time following diagnosis and treatment. The association between emotional acceptance and sickness symptoms was significantly different from zero but relatively small in comparison to the range of sickness symptoms. Results suggest that targeting emotion regulation may help to break the cycle between inflammation and sickness symptoms in women with breast cancer.

Psychological stress and the longitudinal progression of subclinical atherosclerosis.

OBJECTIVE: In a midlife sample of adults, the present study tested the extent to which changes in psychological stress relate to the progression of subclinical cardiovascular disease over multiple years and explored the potential moderating role of cardiometabolic risk. METHOD: Participants were screened to exclude those with clinical cardiovascular, respiratory, metabolic, and other chronic illnesses, as well as those taking psychotropic, cardiovascular, lipid, and glucose control medications. At baseline (N = 331) and then again at follow-up an average of 3 years later (N = 260), participants completed the 10-item Perceived Stress Scale, underwent assessments of their cardiometabolic risk, and underwent ultrasonography to measure carotid artery intima-media thickness (IMT), which is a surrogate indicator of subclinical atherosclerosis. RESULTS: Regression models showed that the change in psychological stress from baseline to follow-up was positively associated with the corresponding change in IMT, with covariate control for age at baseline, sex at birth, and variability in length of follow-up across participants. Cardiometabolic risk factors did not statistically moderate this longitudinal association. In exploratory analyses, cardiometabolic risk factors also did not statistically mediate this association. CONCLUSION: These longitudinal findings suggest that increases in psychological stress in midlife relate to corresponding increases in subclinical atherosclerosis. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Childhood trauma and hair cortisol response over the year following onset of a chronic life event stressor.

OBJECTIVE: Childhood trauma may contribute to poor lifelong health in part through programming of the HPA-axis response to future life stressors. To date, empirical evidence shows an association of childhood trauma with dysregulation of the HPA-axis and blunted cortisol reactivity to acute stressors. Here, we conduct an initial examination of childhood trauma as a moderator of changes over time in perceived stress levels and HPA-axis response to a major chronic stressor in adulthood. METHODS: Participants were 83 maternal caregivers of children newly diagnosed with cancer who completed the Childhood Trauma Questionnaire (CTQ), and who, over the year following their child's cancer diagnosis, had hair samples collected up to 7 times for the assessment of cortisol and completed monthly measures of perceived stress. RESULTS: CTQ scores were in the expected range for a community sample and associated with changes in perceived stress and cortisol concentration over time (γ =.003, p =.002; γ = -.0004, p =.008, respectively) independently of age, education, treatment intensity and randomization to stress management intervention. Maternal caregivers who endorsed lower childhood trauma showed a steeper decline in perceived stress and a larger increase in cortisol levels across the year than caregivers who recalled more childhood trauma. CONCLUSIONS: Findings extend animal models and studies that examine cortisol reactivity to acute stressors and suggest that childhood trauma may program a phenotype that is more psychologically reactive but shows a blunted HPA-axis response to chronic stress. While adaptive in the short-term, this early life programming may incur long-term costs for health. Further work is warranted to examine this possibility.

Global positioning system watches for estimating energy expenditure.

Global positioning system (GPS) watches have been introduced commercially, converting frequent measurements of time, location, speed (pace), and elevation into energy expenditure (EE) estimates. The purpose of this study was to compare EE estimates of 4 different GPS watches (Forerunner, Suunto, Polar, Adeo), at various walking speeds, with EE estimate from a triaxial accelerometer (RT3), which was used as a reference measure in this study. Sixteen healthy young adults completed the study. Participants wore 4 different GPS watches and an RT3 accelerometer and walked at 6-minute intervals on an outdoor track at 3 speeds (3, 5, and 7 km/hr). The statistical significance of differences in EE between the 3 watches was assessed using linear contrasts of the coefficients from the overall model. Reliability across trials for a given device was assessed using intraclass correlation coefficients as estimated in the mixed model. The GPS watches demonstrated lower reliability (intraclass correlation coefficient) across trials when compared with the RT3, particularly at the higher speed, 7 km/hr. Three GPS watches (Forerunner, Polar, and Suunto) significantly and consistently underestimated EE compared with the reference EE given by the RT3 accelerometer (average mean difference: Garmin, -50.5%; Polar, -41.7%; and Suunto, -41.7%; all p < 0.001). Results suggested that caution should be exercised when using commercial GPS watches to estimate EE in athletes during field-based testing and training.

Positive social factors prospectively predict younger epigenetic age: Findings from the Health and Retirement Study.

OBJECTIVES: Positive social factors may slow biological aging, but this has yet to be rigorously tested. This study investigated whether baseline levels or changes over time in social support and contact frequency prospectively predicted epigenetic age. METHOD: Health and Retirement Study participants (N = 1912, 46.3 % male, aged 42-87 at baseline) reported longitudinal social support and contact frequency data up to 3 times between 2006 and 2016 and provided blood in 2016. Baseline levels (intercepts) and changes over time (slopes) in social support from and contact frequency with spouses, children, friends, and other family were outputted from multilevel models and used to predict epigenetic age, estimated from Horvath, Hannum, GrimAge, PhenoAge, and Dunedin Pace of Aging. RESULTS: In models adjusted for demographic and health characteristics, higher baseline levels of support from and contact frequency with friends were prospectively associated with a slower Pace of Aging (support: p = .002; contact: p = 0.009) and a lower GrimAge (contact: p = .001). In addition, higher contact frequency with children at baseline was prospectively associated with a lower GrimAge (p < .001), and higher contact frequency with family at baseline and an increase in family contact over time was associated with a lower Hannum age (baseline: p = .005; slope: p = .015). CONCLUSIONS: Perceived support from and contact with close others, particularly friends, may have implications for healthy biological aging. Notably, the effect sizes for friends were comparable to the effect of body mass index on epigenetic age. Positive social factors were generally associated with second- and third-generation clocks, which may be more sensitive to psychosocial factors than first-generation clocks.

Resources and lymphocyte terminal maturity among older adults.

OBJECTIVE: Women's financial resources were associated with more terminal maturity in natural killer lymphocytes, generally associated with loss of proliferative potential, during the "Great Recession". This preregistered analysis expanded on that finding in a longitudinal design including both genders and examining the role of cytomegalovirus (CMV) serostatus. METHOD: Older adults (N = 138, 57% women) were assessed longitudinally during 2012-2017; including self-reported psychological, social, financial, and status-skill resources, CMV antibody titers and serostatus, and assessment of T and natural killer lymphocyte terminal maturity (LTM). RESULTS: Neither total nor financial resources were associated with LTM. Adjusting only for age, more psychological resources (e.g., meaning, hope, humor) were associated with lower T LTM (percent: γ = -1.11 [-1.78, -.44]; number: γ = -.99 [-1.70, -.27]). There were no significant interactions with age, gender, or CMV serostatus; however, additionally adjusting for serostatus reduced the effect of psychological resources (percent: γ = -.41 [-93, .12]; number: (γ = -.40 [-.94, .13]). CONCLUSIONS: Outside the context of the "Great Recession", psychological resources but not financial resources were associated with terminal maturity in T cells, a relationship related to CMV serostatus. Further studies in different and more diverse samples, and in different eras, are needed to understand what resources are most protective against immunological aging, when, and for whom. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Does an Online Positive Psychological Intervention Improve Positive Affect in Young Adults During the COVID-19 Pandemic?

Meta-analyses indicate that positive psychological interventions are effective at increasing positive affect, as well as reducing anxiety and depression; however, it is unclear how well these effects generalize during periods of high stress. Therefore, the current study tested whether a 2-week online positive psychological intervention delivered during the COVID-19 pandemic, a naturalistic stressor, (1) increased positive affect; (2) improved psychological well-being, optimism, life satisfaction, perceived social support, and loneliness; (3) and reduced negative affect in college students, a group known to have high pandemic distress. Participants (N = 250; 76.9% female) ages 18-45 were recruited from the University of Pittsburgh undergraduate subject pool between September and November of 2020. Participants were randomized to the online positive psychological intervention or active control condition and stratified by trait positive affect, sex, and year in college. Participants in both conditions completed one writing activity every other day for two consecutive weeks. Control participants documented their activities for that day (e.g., meals, going to gym). Intervention participants chose from six positive psychology activities. All outcome variables were assessed pre- and post-intervention by validated questionnaires. Across both conditions, positive and negative affect decreased from pre- to post-intervention. No other psychological factor differed by condition, time, or their interaction. The current null findings are in line with a more recent meta-analysis indicating that positive psychological interventions may have smaller effects on psychological well-being and depressive symptoms than was reported pre-pandemic. Study findings may suggest reduced efficacy of virtual positive psychological interventions under highly stressful circumstances. Supplementary Information: The online version contains supplementary material available at 10.1007/s42761-022-00148-z.

DNA methylation-based measures of biological aging and cognitive decline over 16-years: preliminary longitudinal findings in midlife.

DNA methylation-based (DNAm) measures of biological aging associate with increased risk of morbidity and mortality, but their links with cognitive decline are less established. This study examined changes over a 16-year interval in epigenetic clocks (the traditional and principal components [PC]-based Horvath, Hannum, PhenoAge, GrimAge) and pace of aging measures (Dunedin PoAm, Dunedin PACE) in 48 midlife adults enrolled in the longitudinal arm of the Adult Health and Behavior project (56% Female, baseline AgeM = 44.7 years), selected for discrepant cognitive trajectories. Cognitive Decliners (N = 24) were selected based on declines in a composite score derived from neuropsychological tests and matched with participants who did not show any decline, Maintainers (N = 24). Multilevel models with repeated DNAm measures within person tested the main effects of time, group, and group by time interactions. DNAm measures significantly increased over time generally consistent with elapsed time between study visits. There were also group differences: overall, Cognitive Decliners had an older PC-GrimAge and faster pace of aging (Dunedin PoAm, Dunedin PACE) than Cognitive Maintainers. There were no significant group by time interactions, suggesting accelerated epigenetic aging in Decliners remained constant over time. Older PC-GrimAge and faster pace of aging may be particularly sensitive to cognitive decline in midlife.

An online Trier social stress paradigm to evoke affective and cardiovascular responses.

In response to the COVID-19 pandemic, prior studies have modified the Trier Social Stress Test to be conducted remotely. The current study aimed to extend these studies to test whether a remote Trier Social Stress Test (rTSST) can elicit (a) affective, (b) blood pressure, and (c) heart rate responses relative to a control condition and whether these responses were reliable when assessed 1 week later. Participants (N = 99, 19.7 ± 3.5 years, 55% female) were randomized to a control or stress condition. Participants received blood pressure monitors in person. Controls completed easier versions of the tasks with a single, friendly researcher. Stress participants performed more difficult versions of the task in front of two judges who participants believed were rating their performance. Blood pressure and heart rate were measured every 2 min throughout, while affect was assessed at baseline, after the final task, and following recovery. The rTSST was feasible to administer with minimal technical issues reported. Participants reported lower positive affect and higher negative affect during the tasks in the stress condition relative to controls. Similarly, stress participants had higher cardiovascular responses during the tasks relative to controls, except that blood pressure was not elevated during mental arithmetic in stress participants relative to controls. Cardiovascular responses demonstrated good test-retest reliability when assessed 1 week later, especially when computed using area under the curve methods. Overall, a rTSST can be used to elicit affective and cardiovascular reactivity and provides an opportunity to increase the accessibility of research participation among diverse populations.

The role of late-differentiated T cells, a proxy for IFN-γ-production, in older adults' social networks.

Interferon-γ (IFN-γ), an inflammatory biomarker that promotes antiviral immunity, may be a prerequisite for sociability. IFN-γ production in older adulthood is driven by late-differentiated CD8+ T cells, particularly CD28-and CD57+ subsets, which increase with age, reduce immune response, and increase chronic disease risk. The present study investigated the relationship between late-differentiated T cells (LDTC) and sociability in a longitudinal study of healthy aging. 139 older adults (Mage = 77.95, range 65-93; 58% female, 57% college educated, and 94% Caucasian) provided data at up to 10 occasions (M = 7). Social network size and diversity and cytomegalovirus (CMV) status were collected at every wave. Percentage of LDTC was measured at up to 4 waves and averaged for each participant. There were no significant main effects of LDTC or interactions between LDTC and time on social network size or diversity. Adjustment for baseline age, gender, and sensitivity analyses including CMV and imputed data did not change results. IFN-γ may not play a role in dictating social behavior in older adults. Alternately, LDTC may not have accurately represented circulating levels of IFN-γ. Future work should continue exploring IFN-γ and social behavior, particularly as it relates to age-related changes. The role of IFN-γ-producing, late-differentiated T cells in older adults' social networks.

Eudaemonic Well-Being in Midlife Women: Change in and Correspondence Between Concurrent and Retrospective Reports.

Concurrent and retrospective reports correspond for personality, affect, and coping. The present study described how autonomy, competence, and relatedness components of eudaemonic well-being (EWB) change over days and months and tested correspondences of daily and retrospective reports between and within people. Midlife and older (50-75 years) women (N = 200) completed online diaries daily for 1 week for 9 bursts over 2 years and answered questionnaires at the end of each burst (burst n = 1,529). Multilevel models partialed levels of variance and tested correspondence. Women varied in their daily experiences of EWB but did not vary substantially between bursts. Burst-level diary means and questionnaire responses corresponded between people, but changes within people were less strongly related. The daily, but not monthly, time scale of change is important for capturing within-person changes in EWB. Finding EWB change over months to years may depend on measurement designed to capture medium-term change.

Mitochondrial phenotypes in purified human immune cell subtypes and cell mixtures.

Using a high-throughput mitochondrial phenotyping platform to quantify multiple mitochondrial features among molecularly defined immune cell subtypes, we quantify the natural variation in mitochondrial DNA copy number (mtDNAcn), citrate synthase, and respiratory chain enzymatic activities in human neutrophils, monocytes, B cells, and naïve and memory T lymphocyte subtypes. In mixed peripheral blood mononuclear cells (PBMCs) from the same individuals, we show to what extent mitochondrial measures are confounded by both cell type distributions and contaminating platelets. Cell subtype-specific measures among women and men spanning four decades of life indicate potential age- and sex-related differences, including an age-related elevation in mtDNAcn, which are masked or blunted in mixed PBMCs. Finally, a proof-of-concept, repeated-measures study in a single individual validates cell type differences and also reveals week-to-week changes in mitochondrial activities. Larger studies are required to validate and mechanistically extend these findings. These mitochondrial phenotyping data build upon established immunometabolic differences among leukocyte subpopulations, and provide foundational quantitative knowledge to develop interpretable blood-based assays of mitochondrial health.