Kirstin Aschbacher

University of California, San Francisco | UCSF · Department of Psychiatry

Background: Chronic psychological stress is a risk factor for cardiovascular disease and mortality. Circulating hematopoietic progenitor cells (CPCs) maintain vascular homeostasis, correlate with preclinical atherosclerosis, and prospectively predict cardiovascular events. We hypothesize that 1) chronic caregiving stress is related to reduced CPC...

Chronic psychological stress appears to accelerate biological aging, and oxidative damage is an important potential mediator of this process. However, the mechanisms by which psychological stress promotes oxidative damage are poorly understood. This study investigates the theory that cortisol increases in response to an acutely stressful event have...

Unlabelled: Cognitive and affective responses to acute stress influence pro-inflammatory cytokine reactivity, and peripheral cytokines (particularly interleukin-1 beta (IL-1β)), can act on the brain to promote depressive symptoms. It is unknown whether acute stress-induced changes in positive affect and cognitions (POS) and pro-inflammatory reacti...

Many individuals with obesity report overeating despite intentions to maintain or lose weight. Two barriers to long-term weight loss are reward-driven eating, which is characterized by a lack of control over eating, a preoccupation with food, and a lack of satiety; and psychological stress. Mindfulness training may address these barriers by promoti...

A dynamic systems model was used to generate parameters describing a phenotype of Hypothalamic-Pituitary-Adrenal (HPA) behavior in a sample of 36 patients with chronic fatigue syndrome (CFS) and/or fibromyalgia (FM) and 36 case-matched healthy controls. Altered neuroendocrine function, particularly in relation to somatic symptoms and poor sleep qua...

Purpose: Heart rate variability biofeedback (HRVB) is an efficacious treatment for depression and anxiety. However, translation to digital mental health interventions (DMHI) is hindered by the lack of normative data for real-time HRVB metrics, without which, biofeedback risks reduced engagement and efficacy. Methods: We analyzed HRVB data from 5,1...

[This corrects the article DOI: 10.3389/fendo.2022.769951.].

The prevalence of obesity is increasing around the world at an alarming rate. The interplay of the hormone leptin with the hypothalamus-pituitary-adrenal axis plays an important role in regulating energy balance, thereby contributing to obesity. This study presents a mathematical model, which describes hormonal behavior leading to an energy abnorma...

Excess alcohol use is an important determinant of death and disability. Machine learning (ML)-driven interventions leveraging smart-breathalyzer data may help reduce these harms. We developed a digital phenotype of long-term smart-breathalyzer behavior to predict individuals’ breath alcohol concentration (BrAC) levels trained on data from a smart b...

Early childhood is a developmental period characterized by significant plasticity, heterogeneity in behaviors and biological functioning. Yet, cumulative cortisol secretion, as measured by hair cortisol, has not been examined longitudinally in relation to change in behavioral problems in young children. The current study examined cross-sectional an...

Early childhood and pregnancy are two sensitive periods of heightened immune plasticity, when exposure to adversity may disproportionately increase health risks. However, we need deeper phenotyping to disentangle the impact of adversity during sensitive periods from that across the total lifespan. This study examined whether retrospective reports o...

Inflammatory pathways predict antidepressant treatment non-response among individuals with major depression; yet, this phenomenon may have broader transdiagnostic and transtherapeutic relevance. Among trauma-exposed mothers (Mage=32 years) and their young children (M=4 years), we tested whether genomic and proteomic biomarkers of pro-inflammatory i...

Background Commercially acquired wearable activity trackers such as the Fitbit provide objective, accurate measurements of physically active time and step counts, but it is unclear whether these measurements are more clinically meaningful than self-reported physical activity. Objective The aim of this study was to compare self-reported physical ac...

Elevated core temperature constitutes an important biomarker for COVID-19 infection; however, no standards currently exist to monitor fever using wearable peripheral temperature sensors. Evidence that sensors could be used to develop fever monitoring capabilities would enable large-scale health-monitoring research and provide high-temporal resoluti...

The global burden of diabetes is rapidly increasing, from 451 million people in 2019 to 693 million by 20451. The insidious onset of type 2 diabetes delays diagnosis and increases morbidity2. Given the multifactorial vascular effects of diabetes, we hypothesized that smartphone-based photoplethysmography could provide a widely accessible digital bi...

Elevated core temperature constitutes an important biomarker for COVID-19 infection; however, no standards currently exist to monitor fever using wearable peripheral temperature sensors. Evidence that sensors could be used to develop fever monitoring capabilities would enable large-scale health-monitoring research and provide high-temporal resoluti...

BACKGROUND Commercially acquired wearable activity trackers such as the Fitbit provide objective, accurate measurements of physically active time and step counts, but it is unclear whether these measurements are more clinically meaningful than self-reported physical activity. OBJECTIVE The aim of this study was to compare self-reported physical ac...

Background Atrial fibrillation (AF), a common cause of stroke, often is asymptomatic. Smartphones and smartwatches can detect AF using heart rate patterns inferred using photoplethysmography (PPG); however, enhanced accuracy is required to reduce false positives in screening populations. Objective The purpose of this study was to test the hypothes...

When is psychological stress “good” or “bad” for our health? There is no straightforward answer. In this chapter, we first address this question with a review of the best principles for the measurement of psychological distress and stressor exposures in human psychobiological studies. Next, we review the associations between psychological distress...

Self-weighing may promote attainment and maintenance of healthy weight; however, the natural temporal patterns and factors associated with self-weighing behavior are unclear. The aims of this secondary analysis were to (1) identify distinct temporal patterns of self-weighing behaviors; (2) explore factors associated with temporal self-weighing patt...

Emerging technology allows patients to measure and record their heart rate (HR) remotely by photoplethysmography (PPG) using smart devices like smartphones. However, the validity and expected distribution of such measurements are unclear, making it difficult for physicians to help patients interpret real-world, remote and on-demand HR measurements....

Objective To assess the effect of cannabis legalisation on health effects and healthcare utilisation in Colorado (CO), the first state to legalise recreational cannabis, when compared with two control states, New York (NY) and Oklahoma (OK). Design We used the 2010 to 2014 Healthcare Cost and Utilisation Project (HCUP) inpatient databases to compa...

In general, glucose consumption improves cognitive performance; however, it is unknown whether glucose specifically alters attentional food bias, and how this process may vary by BMI status. We hypothesized that glucose consumption would increase attentional food bias among individuals of obese BMI status more so than among individuals of lean BMI...

Background: Chronic caregiving stress may accelerate biological aging; however, the ability to integrate the meaning of caregiving through self-awareness, adaptation, and growth can buffer the negative effects of stress. Narrative researchers have shown that people who coherently integrate difficult experiences into their life story tend to have b...

Introduction: Heart rate (HR) is a key cardiovascular vital sign. Clinicians currently use normal values, without consideration of age, that are derived from small-scale observational studies and expert opinion. Our objective was to define age-specific resting HR values, obtained in participants' everyday life, using a smartphone app that measures...

Introduction: Heart rate (HR) is an important vital sign that can be influenced by the presence of systemic inflammation, atherosclerosis and disease. Our objective was to define the HR values based on disease state and use of chronotropic medication, measured using a smartphone app.

Posttraumatic stress disorder (PTSD) is associated with abnormalities in functional connectivity of a specific cortico-limbic network; however, less is known about white matter abnormalities providing structural connections for this network. This study investigated whether the diagnosis and symptoms of PTSD are associated with alterations in fracti...

Objectives: Anger expression is assumed to have mostly negative health effects. Yet, evidence is mixed on how anger expression influences African Americans' cardiovascular health. The present research aimed to clarify this link by examining moderating effects of chronic discrimination on the relationship between anger expression and cardiovascular...

Objective The aim of this study was to examine whether baseline chronic stress and impulsive risk‐taking synergistically predict changes in visceral fat among healthy mothers in an observational, longitudinal, 18‐month study. Methods A prospective cohort of 113 adult women (age, mean ± SD: 42.83 ± 4.70; BMI, mean ± SD: 24.86 ± 4.32; 74%, n = 84 wh...

Background Chronic life stress, such as the stress of caregiving, can promote pathophysiology, but the underlying cellular mechanisms are not well understood. Chronic stress may induce recalibrations in mitochondria leading to either changes in mitochondrial content per cell, or in mitochondrial functional capacity (i.e., quality). Methods Here we...

Inflammation is reported in post-traumatic stress disorder (PTSD). Few studies have investigated circulating blood cells that may contribute to inflammation. We assessed circulating platelets, white blood cells (WBC) and red blood cells (RBC) in PTSD and assessed their relationship to inflammation and symptom severity. One-hundred and sixty-three m...

Objectives This study aimed to evaluate the effect of a stress management intervention (SMI) on lasting return to work (RTW) among patients with work-related stress complaints. Methods Sickness benefit departments from three local municipalities referred patients on sick leave with work-related adjustment disorders or mild depression to the Departm...

Table S1. Characteristics of Patients by Quartiles of the PTSD Checklist Table S2. Brachial Artery Flow‐Mediated Vasodilation by Sample Quartiles of the PTSD Checklist Score

Background Current research in behavioral cardiology reveals a significant association between posttraumatic stress disorder (PTSD) and increased risk for cardiovascular disease and mortality; however, the underlying mechanisms remain poorly understood. We hypothesized that patients with PTSD would exhibit endothelial dysfunction, a potential mecha...

Introduction: Post-traumatic stress disorder (PTSD) has been associated with immune disturbances, including a higher incidence of infections and autoimmune diseases as well as a net pro-inflammatory state. Natural killer (NK) cells, a key component of the innate immune system, have been less well-studied in PTSD despite their importance in immunit...

Background Circulating angiogenic cells (CACs) are peripheral blood cells whose functional capacity inversely correlates with cardiovascular risk and that have therapeutic benefits in animal models of cardiovascular disease. However, donor age and disease state influence the efficacy of autologous cell therapy. We sought to determine whether age or...

Telomeres, the protective DNA-protein complexes at the ends of linear chromosomes, are important for genome stability. Leukocyte or peripheral blood mononuclear cell (PBMC) telomere length is a potential biomarker for human aging that integrates genetic, environmental, and lifestyle factors and is associated with mortality and risks for major disea...

Table S1 provides the means and SD's of telomere length and telomerase activity for the 39 subjects with longitudinal telomere length data (N=39). Table S2 provides the means and SD's of telomere length and telomerase activity of the entire cohort at base visit. Table S3 compares telomere length of different cell types from the same individual at b...

Introduction: Treatment of myocardial infarction (MI) with bone marrow cells (BMCs) or cell-free BMC lysate substantially improves post-MI cardiac function in rodent experiments. However, clinical trials of BMC therapy have been less successful. While most mouse experiments use young healthy BMC donors, MI patients undergoing autologous cell therap...

Background Circulating hematopoietic progenitor cells (PCs; CD34+ and CD34+/KDR+) facilitate neurogenesis and neovascularization, promoting increased cortical thickness and white matter integrity in animal models. However, it unknown whether low PCs are associated with trauma symptoms or neurovascular health among veterans. Objectives Determine whe...

Glucocorticoids contribute to obesity and metabolic syndrome; however, the mechanisms are unclear, and prognostic measures are unavailable. A systems level understanding of the hypothalamic-pituitary-adrenal (HPA)-leptin axis may reveal novel insights. Eighteen obese premenopausal women provided blood samples every 10 min over 24 h, which were assa...

Social connections moderate the effects of high negative affect on health. Affective states (anger, fear, and anxiety) predict interleukin-6 (IL-6) reactivity to acute stress; in turn, this reactivity predicts risk of cardiovascular disease progression. Here, we examined whether perceived social support mitigates the relationship between negative a...

We sought to determine the effects of brief exposures to low concentrations of tobacco secondhand smoke (SHS) on arterial flow-mediated dilation (FMD, a nitric oxide-dependent measure of vascular endothelial function), in a controlled animal model never before exposed to smoke. In humans, SHS exposure for 30min impairs FMD. It is important to gain...

With improvements in medical care, individuals are living longer than any time in human history. However, with age comes increasing susceptibility to a cadre of age-related illnesses, including cardiovascular disease, diabetes, arthritis, and cancer. While chronological age remains the best predictor of disease onset, the rates at which these disea...

With improvements in medical care, individuals are living longer than any time in human history. However, with age comes increasing susceptibility to a cadre of age-related illnesses, including cardiovascular disease, diabetes, arthritis, and cancer. While chronological age remains the best predictor of disease onset, the rates at which these disea...

Current studies suggest that A-allele carriers of the OXTR SNP rs53576 have greater social stress vulnerability. The biological sensitivity to context theory (Boyce and Ellis) suggests that high-reactivity phenotypes exhibit risk-augmenting or risk-protective responses depending on social context. We examined rs53576 allele variation on affective a...

Rationale : Chronic stress has been related to lower telomerase, an enzyme that helps preserve the integrity of DNA and slow immunological aging. However, it is unknown whether daily psychological processes reflecting healthy emotion regulation protect against stress-related immune-aging. Methods : We examined basal telomerase activity in a sample...

Chronic or severe acute elevations in plasma glucose are associated with decreases in the number and function of circulating angiogenic cells (CACs). However, less is known about whether fasting plasma glucose levels (FPG) within the normal or pre-diabetic range among healthy individuals are associated with decreased CAC function. Establishing this...

Background / Purpose: Cognitive and affective responses to acute stress influence pro-inflammatory cytokine reactivity, and peripheral cytokines can act on the brain to promote depressive symptoms. However, it is unknown whether acute stress-induced changes in positive affect and cognitions (POS) and pro-inflammatory reactivity predict future lev...

Abstract: The effect of parameter perturbations on the trajectories of dynamical systems has been extensively studied in the literature. The effect of parameter values on the number and type of rest-points in a dynamical system has received less attention. For systems that exhibit input multiplicities, the sensitivity of system trajectories to para...

This study aimed to determine if Alzheimer caregivers have increased allostatic load compared to non-caregivers. Potential psychological moderators (mastery, depression, and role overload) of the relationship between caregiving status and allostatic load were also explored. Eighty-seven caregivers and 43 non-caregivers underwent biological assessme...

The identifiability and estimability properties of dynamical systems have been extensively studied in the literature. However, such approaches often focus on the sensitivity of system trajectories to perturbations in parameter values about some nominal parameter value. Relying on parameter sensitivity to assess parameter estimability can be mislead...

Platelet reactivity to acute stress is associated with increased cardiovascular disease risk; however, little research exists to provide systematic methodological foundations needed to generate strong longitudinal research designs. Study objectives were: 1) to evaluate whether markers of platelet function increase in response to an acute psychologi...

A substantial proportion of chronically-stressed spousal dementia caregivers report fatigue. The objective of this study was to examine whether personal mastery moderates the relationship between caregiving status (caregiver/non-caregiver) and multiple dimensions of fatigue. Seventy-three elderly Alzheimer's caregivers and 41 elderly non-caregivers...

Previous research among HIV-infected individuals suggests that spiritual well-being is inversely related to psychological distress and rates of disease progression. Use of a mantram, a spiritual word or phrase repeated frequently and silently throughout the day, has been associated with decreased psychological distress and increased spiritual well-...

Depressive symptoms and caregiving stress may contribute to cardiovascular disease (CVD) via chronic platelet activation; however, it remains unclear whether this elevated activation constitutes a trait or state marker. The primary objective was to investigate whether persistent depressive symptoms would relate to elevated platelet activation in re...

Chronic back pain affects a large proportion of both the general population and of military veterans. Although numerous therapies exist for treating chronic back pain, they can be costly and tend to have limited effectiveness. Thus, demonstrating the efficacy and cost-effectiveness of additional treatment alternatives is important. The purpose of o...

Caring for a spouse with Alzheimer's disease (AD) is associated with overall health decline and impaired cardiovascular functioning. This morbidity may be related to the effects of caregiving stress and impaired coping on beta(2)-adrenergic receptors, which mediate hemodynamic and vascular responses and are important for peripheral blood mononuclea...

Being a caregiver for a spouse with Alzheimer's disease is associated with increased risk for cardiovascular illness, particularly for males. This study examined the effects of caregiver gender and severity of the spouse's dementia on sleep, coagulation, and inflammation in the caregiver. Eighty-one male and female spousal caregivers and 41 non-car...

Spousal caregivers of Alzheimer's disease patients are at increased risk for cardiovascular disease, possibly via sympathetic response to stressors and subsequent catecholamine surge. Personal mastery (i.e., belief that one can manage life's obstacles) may decrease psychological and physiological response to stressors. This study examines the relat...

Caring for a spouse with Alzheimer's disease is associated with increased psychological distress, impaired immunity, and heightened cardiovascular risk. Hyperreactivity of sympathetic and platelet activation responses to acute psychological stress, or the failure to recover quickly from stressful events, may constitute an important pathway linking...

This study tested whether feelings of personal control over one's life circumstances (i.e., personal mastery) would attenuate the relations between stress (i.e., negative life events and caregiving distress) and Plasminogen Activator Inhibitor (PAI)-1 antigen, an inhibitor of fibrinolysis implicated in the development of cardiovascular disease. Sev...

Elderly individuals who provide care to a spouse suffering from dementia bear an increased risk of coronary heart disease (CHD). To test the hypothesis that the Framingham CHD Risk Score would be higher in dementia caregivers relative to non-caregiving controls. We investigated 64 caregivers providing in-home care for their spouse with Alzheimer's...

To investigate the combined effects of caregiving and hormone replacement therapy (HRT) on platelet hyperactivity to acute psychological stress. Both HRT and the chronic stress of caregiving have been associated with increased cardiovascular risk, potentially through a mechanism of platelet hyperactivity. A total of 78 elderly postmenopausal women...

To determine if caregivers of spouses with Alzheimer's disease demonstrate greater increase in tissue plasminogen activator (t-PA) antigen relative to noncaregiving controls. Caring for a spouse with Alzheimer's disease has been associated with increased mortality and reduced time to developing cardiovascular disease (CVD), possibly due to impaired...

A growing body of literature suggests that caregiving burden is associated with impaired immune system functioning, which may contribute to elevated morbidity and mortality risk among dementia caregivers. However, potential mechanisms linking these relationships are not well understood. The purpose of this study was to investigate whether stress-re...