Relationship of Psychological Characteristics to Daily Life Ischemia: An Analysis From the National Heart, Lung, and Blood Institute Psychophysiological Investigations in Myocardial Ischemia

OBJECTIVE

Cardiac ischemia during daily life is associated with an increased risk of adverse outcomes. Mental stress is known to provoke cardiac ischemia and is related to psychological variables. In this multicenter cohort study, we assessed whether psychological characteristics were associated with ischemia in daily life.

METHODS

This study examined patients with clinically stable coronary artery disease (CAD) with documented cardiac ischemia during treadmill exercise (n = 196, mean [standard deviation] age = 62.64 [8.31] years; 13% women). Daily life ischemia (DLI) was assessed by 48-hour ambulatory electrocardiophic monitoring. Psychological characteristics were assessed using validated instruments to identify characteristics associated with ischemia occurring in daily life stress.

RESULTS

High scores on anger and hostility were common in this sample of patients with CAD, and DLI was documented in 83 (42%) patients. However, the presence of DLI was associated with lower anger scores (odds ratio [OR] = 2.03; 95% confidence interval [CI] = 1.12-3.69), reduced anger expressiveness (OR = 2.04; 95% CI = 1.10-3.75), and increased ratio of anger control to total anger (OR = 2.33; 95% CI = 1.27-4.17). Increased risk of DLI was also associated with lower hostile attribution (OR = 2.22; 95% CI = 1.21-4.09), hostile affect (OR = 1.92; 95% CI = 1.03-3.58), and aggressive responding (OR = 2.26; 95% CI = 1.25-4.08). We observed weak inverse correlations between DLI episode frequency and anger expressiveness, total anger, and hostility scores. DLI was not associated with depression or anxiety measures. The combination of the constructs low anger expressiveness and low hostile attribution was independently associated with DLI (OR = = 2.59; 95% CI = 1.42-4.72).

CONCLUSIONS

In clinically stable patients with CAD, the tendency to suppress angry and hostile feelings, particularly openly aggressive behavior, was associated with DLI. These findings warrant a study in larger cohorts, and intervention studies are needed to ascertain whether management strategies that modify these psychological characteristics improve outcomes.

Observation of Complement Protein Gene Expression Before and After Surgery in Opioid-Consuming and Opioid-Naive Patients

Opioids may influence inflammation. We compared genes associated with pain and inflammation in patients who consumed opioids (3-120 mg of oral morphine equivalents per day) with those who did not for differential expression. White blood cells were assayed in 20 patients presenting for total lower extremity joint replacement. We focused on messenger ribonucleic acid expression of complement proteins. We report that the expression of a complement inhibitor, complement 4 binding protein A, was reduced, and the expression of a complement activator, complement factor D, was increased in opioid-consuming patients. We conclude that opioid consumption may influence expression of complement activators and inhibitors.

Gene Variants in Hepatic Metabolism, Gamma-Aminobutyric Acid-ergic Reward, and Prostaglandin Pathways in Opioid-Consuming and Opioid-Naïve Patients Presenting for Lower Extremity Total Joint Replacement

Gene variants may contribute to individual differences in the experience of pain and the efficacy and reward of treatments. We explored gene variation in opioid-naïve and opioid-consuming patients undergoing elective lower extremity total joint replacement. We focused on 3 gene pathways including prostaglandin, gamma-aminobutyric acid (GABA)-ergic reward, and hepatic metabolism pathways. We report that for genes with possible or probable deleterious impact in these 3 pathways, opioid consumers had more gene variants than opioid-naïve patients (median 3 vs 1, P = .0092). We conclude that chronic opiate users may have genetic susceptibility to altered responses in reward/dependency and pain/inflammation pathways.

Propofol for Treatment-Resistant Depression: A Pilot Study

BACKGROUND

We hypothesized that propofol, a unique general anesthetic that engages N-methyl-D-aspartate and gamma-aminobutyric acid receptors, has antidepressant properties. This open-label trial was designed to collect preliminary data regarding the feasibility, tolerability, and efficacy of deep propofol anesthesia for treatment-resistant depression.

METHODS

Ten participants with moderate-to-severe medication-resistant depression (age 18-45 years and otherwise healthy) each received a series of 10 propofol infusions. Propofol was dosed to strongly suppress electroencephalographic activity for 15 minutes. The primary depression outcome was the 24-item Hamilton Depression Rating Scale. Self-rated depression scores were compared with a group of 20 patients who received electroconvulsive therapy.

RESULTS

Propofol treatments were well tolerated by all subjects. No serious adverse events occurred. Montreal Cognitive Assessment scores remained stable. Hamilton scores decreased by a mean of 20 points (range 0-45 points), corresponding to a mean 58% improvement from baseline (range 0-100%). Six of the 10 subjects met the criteria for response (>50% improvement). Self-rated depression improved similarly in the propofol group and electroconvulsive therapy group. Five of the 6 propofol responders remained well for at least 3 months. In posthoc analyses, electroencephalographic measures predicted clinical response to propofol.

CONCLUSIONS

These findings demonstrate that high-dose propofol treatment is feasible and well tolerated by individuals with treatment-resistant depression who are otherwise healthy. Propofol may trigger rapid, durable antidepressant effects similar to electroconvulsive therapy but with fewer side effects. Controlled studies are warranted to further evaluate propofol's antidepressant efficacy and mechanisms of action. ClinicalTrials.gov: NCT02935647.

Neural consequences of post-exertion malaise in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

Post exertion malaise is one of the most debilitating aspects of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome, yet the neurobiological consequences are largely unexplored. The objective of the study was to determine the neural consequences of acute exercise using functional brain imaging. Fifteen female Myalgic Encephalomyelitis/Chronic Fatigue Syndrome patients and 15 healthy female controls completed 30min of submaximal exercise (70% of peak heart rate) on a cycle ergometer. Symptom assessments (e.g. fatigue, pain, mood) and brain imaging data were collected one week prior to and 24h following exercise. Functional brain images were obtained during performance of: 1) a fatiguing cognitive task - the Paced Auditory Serial Addition Task, 2) a non-fatiguing cognitive task - simple number recognition, and 3) a non-fatiguing motor task - finger tapping. Symptom and exercise data were analyzed using independent samples t-tests. Cognitive performance data were analyzed using mixed-model analysis of variance with repeated measures. Brain responses to fatiguing and non-fatiguing tasks were analyzed using linear mixed effects with cluster-wise (101-voxels) alpha of 0.05. Myalgic Encephalomyelitis/Chronic Fatigue Syndrome patients reported large symptom changes compared to controls (effect size ≥0.8, p<0.05). Patients and controls had similar physiological responses to exercise (p>0.05). However, patients exercised at significantly lower Watts and reported greater exertion and leg muscle pain (p<0.05). For cognitive performance, a significant Group by Time interaction (p<0.05), demonstrated pre- to post-exercise improvements for controls and worsening for patients. Brain responses to finger tapping did not differ between groups at either time point. During number recognition, controls exhibited greater brain activity (p<0.05) in the posterior cingulate cortex, but only for the pre-exercise scan. For the Paced Serial Auditory Addition Task, there was a significant Group by Time interaction (p<0.05) with patients exhibiting increased brain activity from pre- to post-exercise compared to controls bilaterally for inferior and superior parietal and cingulate cortices. Changes in brain activity were significantly related to symptoms for patients (p<0.05). Acute exercise exacerbated symptoms, impaired cognitive performance and affected brain function in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome patients. These converging results, linking symptom exacerbation with brain function, provide objective evidence of the detrimental neurophysiological effects of post-exertion malaise.

It's Complicated: Marital Ambivalence on Ambulatory Blood Pressure and Daily Interpersonal Functioning

BACKGROUND

Marriage decreases cardiovascular morbidity although relationship quality matters. While some marriages contain highly positive aspects (supportive), marriages may also simultaneously contain both positive and negative aspects (ambivalent). Individuals whose spouses or own behavior is ambivalent may not experience the same cardiovascular-protective benefits of marriage.

PURPOSE

The purpose of this study is to elucidate the physiological pathways by which marital quality may influence long-term health and examine ambivalent behavior on interpersonal-functioning and ambulatory blood pressure (ABP).

METHODS

Interpersonal functioning and ABP were examined in 94 couples.

RESULTS

Spousal and own ambivalent behavior was associated with lower intimacy (ps < .01) and higher systolic ABP (ps < .01). Spousal ambivalent behavior was associated with lower ratings of partner responsiveness (p < .01) and less self- and spousal-disclosure (ps < .05). Mediational analyses indicated that own behavior mediated links between spousal ambivalent behavior and ABP.

CONCLUSIONS

Despite the positivity in relationships, individuals whose spouses' or own behavior is ambivalent may not receive cardiovascular protection from this positivity.

Gene Expression Factor Analysis to Differentiate Pathways Linked to Fibromyalgia, Chronic Fatigue Syndrome, and Depression in a Diverse Patient Sample

OBJECTIVE

To determine if independent candidate genes can be grouped into meaningful biologic factors, and whether these factors are associated with the diagnosis of chronic fatigue syndrome (CFS) and fibromyalgia syndrome (FMS), while controlling for comorbid depression, sex, and age.

METHODS

We included leukocyte messenger RNA gene expression from a total of 261 individuals, including healthy controls (n = 61), patients with FMS only (n = 15), with CFS only (n = 33), with comorbid CFS and FMS (n = 79), and with medication-resistant (n = 42) or medication-responsive (n = 31) depression. We used exploratory factor analysis (EFA) on 34 candidate genes to determine factor scores and regression analysis to examine whether these factors were associated with specific diagnoses.

RESULTS

EFA resulted in 4 independent factors with minimal overlap of genes between factors, explaining 51% of the variance. We labeled these factors by function as 1) purinergic and cellular modulators, 2) neuronal growth and immune function, 3) nociception and stress mediators, and 4) energy and mitochondrial function. Regression analysis predicting these biologic factors using FMS, CFS, depression severity, age, and sex revealed that greater expression in factors 1 and 3 was positively associated with CFS and negatively associated with depression severity (Quick Inventory for Depression Symptomatology score), but not associated with FMS.

CONCLUSION

Expression of candidate genes can be grouped into meaningful clusters, and CFS and depression are associated with the same 2 clusters, but in opposite directions, when controlling for comorbid FMS. Given high comorbid disease and interrelationships between biomarkers, EFA may help determine patient subgroups in this population based on gene expression.

Fatigue sensation and gene expression in trained cyclists following a 40 km time trial in the heat

PURPOSE

We examined the effect of race-effort cycling exercise with and without heat stress on post-exercise perceptions of fatigue and pain, as well as mRNA expression in genes related to exercise responses.

METHODS

Trained cyclists (n = 20) completed 40 km time trials during temperate (TC, 21 °C) and hot (HC, 35 °C) conditions. Blood lactates were measured 1 and 5 min post-exercise. Venous blood samples and ratings of fatigue and pain perceptions were obtained at baseline and at 0.5, 8, 24, and 48 h post-exercise. Leukocyte mRNA expression was performed for metabolite detecting, adrenergic, monoamine, and immune receptors using qPCR.

RESULTS

Significantly lower mean power (157 ± 32.3 vs 187 ± 40 W) and lactates (6.4 ± 1.7 vs 8.8 ± 3.2 and 4.2 ± 1.5 vs 6.6 ± 2.7 mmol L(-1) at 1- and 5-min post-exercise) were observed for HC versus TC, respectively (p < 0.05). Increases (p < 0.05) in physical fatigue and pain perception during TTs did not differ between TC and HC (p > 0.30). Both trials resulted in significant post-exercise decreases in metabolite detecting receptors ASIC3, P2X4, TRPV1, and TRPV4; increases in adrenergic receptors α2a, α2c, and β1; decreases in adrenergic β2, the immune receptor TLR4, and dopamine (DRD4); and increases in serotonin (HTR1D) and IL-10 (p < 0.05). Post-exercise IL-6 differed between TC and HC, with significantly greater increases observed following HC (p < 0.05).

CONCLUSIONS

Both TT performances appeared to be regulated around a specific sensory perception of fatigue and pain. Heat stress may have compensated for lower lactate during HC, thereby matching changes in metabolite detecting and other mRNAs across conditions.

Blood pressure, salivary cortisol, and inflammatory cytokine outcomes in senior female cancer survivors enrolled in a tai chi chih randomized controlled trial

PURPOSE

Older cancer survivors are a vulnerable population due to an increased risk for chronic diseases (e.g., cardiovascular disease) compounded with treatment late-effects and declines in physical functioning. Therefore, interventions that reduce chronic disease risk factors (i.e., blood pressure, chronic inflammation, and cortisol) are important in this population. Tai chi chih (TCC) is a mind-body exercise associated with reductions in chronic disease risk factors, but has not been examined with older cancer survivors. In a feasibility randomized controlled trial of TCC, we examined secondary outcomes of blood pressure, salivary cortisol, and inflammatory cytokines (interleukin (IL)-6, IL-12, tumor necrosis factor-α, IL-10, IL-4) due to their implications in chronic diseases.

METHODS

Sixty-three senior female cancer survivors (M age = 67 years, SD = 7.15) with physical functioning limitations (SF-12 physical functioning ≤80 or role-physical ≤72) were randomized to 12-weeks (60-min, three times a week) of TCC or Health Education control (HEC) classes. Resting blood pressure, 1-day salivary cortisol samples, and fasting plasma samples for cytokine multiplex assays were collected at baseline and 1-week post-intervention.

RESULTS

Controlling for baseline values, the TCC group had significantly lower systolic blood pressure (SBP, p = 0.002) and cortisol area-under-curve (AUC, p = 0.02) at post-intervention than the HEC group. There was no intervention effect on inflammatory cytokines (p's > 0.05).

CONCLUSIONS

This TCC feasibility trial was associated with significant reductions in SBP and cortisol AUC in senior female cancer survivors. Larger, definitive trials are needed to confirm these findings.

IMPLICATIONS FOR CANCER SURVIVORS

Senior survivors' have an increased risk for chronic diseases; however, TCC interventions may help reduce associated risk factors.

A cross-sectional analysis of the association between perceived network social control and telomere length

OBJECTIVE

Social control in the health domain refers to attempts by social network members to get an individual to modify their health behaviors. According to the dual effects model of social control, having one's health behavior controlled by others should be related to healthier behavioral change, but might arouse psychological distress as one may resent being controlled. Despite potential healthy behavior change, the stress of social control may thus be detrimental as interpersonal stress has been related to negative health outcomes. In the present study, the association between perceived social control and telomere length was tested to examine its association to biological outcomes.

METHOD

In this cross-sectional study, a relatively healthy community sample of 140 middle age and older adults completed measures of perceived social control, perceived stress, and health behaviors. Peripheral blood mononuclear cells were used to determine telomere length.

RESULTS

Main results showed that higher levels of perceived direct social network control were associated with shorter telomere length. These links were not influenced by statistical controls for medication use, self-rated health, trait hostility, and optimism. Perceived social control was also related to greater perceived stress but not health behaviors overall. However, neither perceived stress nor health behaviors mediated the link between social control and telomere length.

CONCLUSIONS

Although the study design precludes strong inferences, these results suggest that perceived social control may be associated with cellular aging. These data also highlight the utility of integrating biological outcomes into social control models. (PsycINFO Database Record

Cellular aging and restorative processes: subjective sleep quality and duration moderate the association between age and telomere length in a sample of middle-aged and older adults

STUDY OBJECTIVES

To examine whether subjective sleep quality and sleep duration moderate the association between age and telomere length (TL).

DESIGN

Participants completed a demographic and sleep quality questionnaire, followed by a blood draw.

SETTING

Social Neuroscience Laboratory.

PARTICIPANTS

One hundred fifty-four middle-aged to older adults (age 45-77 y) participated. Participants were excluded if they were on immunosuppressive treatment and/or had a disease with a clear immunologic (e.g., cancer) component.

INTERVENTIONS

N/A.

MEASUREMENTS AND RESULTS

Subjective sleep quality and sleep duration were assessed using the Pittsburgh Sleep Quality Index (PSQI) and TL was determined using peripheral blood mononuclear cells (PBMCs). There was a significant first-order negative association between age and TL. Age was also negatively associated with the self-reported sleep quality item and sleep duration component of the PSQI. A significant age × self-reported sleep quality interaction revealed that age was more strongly related to TL among poor sleepers, and that good sleep quality attenuated the association between age and TL. Moreover, adequate subjective sleep duration among older adults (i.e. greater than 7 h per night) was associated with TL comparable to that in middle-aged adults, whereas sleep duration was unrelated to TL for the middle-aged adults in our study.

CONCLUSIONS

The current study provides evidence for an association between sleep quality, sleep duration, and cellular aging. Among older adults, better subjective sleep quality was associated with the extent of cellular aging, suggesting that sleep duration and sleep quality may be added to a growing list of modifiable behaviors associated with the adverse effects of aging.

The stress-buffering effects of functional social support on ambulatory blood pressure

OBJECTIVE

Social support is a reliable predictor of cardiovascular health. According to the buffering hypothesis, stress is 1 mechanism by which support is able to affect physiological processes. However, most of the experimental evidence for the hypothesis comes from laboratory studies. Ambulatory blood pressure (ABP) protocols examine participants in their natural environment, where they are more likely to encounter personally relevant real-world stressors. Furthermore, prior work shows that examining support by its specific functional components reveals additional independent links to health.

METHODS

The current study aimed to examine the stress-buffering effects of functional social support on ABP. One hundred eighty-eight participants completed a 1-day ABP assessment along with measures of functional social support and both global perceived stress and momentary stress at time of reading.

RESULTS

RESULTS indicated main effects for both stress measures. Global support, emotional, tangible, and informational support only moderated the effects of momentary stress, but not global stress, in predicting ABP. Informational support was the most consistent stress-buffering predictor of ABP, predicting both ambulatory systolic and diastolic blood pressure.

CONCLUSIONS

The predicted values in ABP for informational support achieved health-relevant differences, emphasizing the value of examining functional support beyond global support alone.

Levels of fatigue and distress in senior prostate cancer survivors enrolled in a 12-week randomized controlled trial of Qigong

PURPOSE

Fatigue is a commonly reported symptom by prostate cancer survivors and is associated with significant distress and declines in quality of life. Qigong is a mind-body activity that consists of both physical activity and meditative aspects. This 12-week randomized controlled trial examined the feasibility and efficacy of a Qigong intervention for improving older prostate cancer survivors' levels of fatigue and distress.

METHODS

Forty older (median age = 72, range = 58-93), fatigued (cut-off value of ≥ 1 on the CTCAEv4.0, >20 on a fatigue grading scale), and sedentary (<150 min of moderate exercise/week) prostate cancer survivors were randomized to 12 weeks of Qigong or stretching classes. Primary outcomes were feasibility (i.e., retention and class attendance rates) and fatigue [Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-Fatigue)], and secondary outcome was distress [Brief Symptom Inventory-18 (BSI-18)].

RESULTS

Study retention rates did not significantly differ between study groups (Qigong = 80 %, stretching = 65 %, p = 0.48). The Qigong group had significantly higher class attendance than the stretching group (p = 0.04). The Qigong group had significantly greater improvements in the FACIT-Fatigue (p = 0.02) and distress (i.e., BSI-18 Somatization, Anxiety, & Global Severity Index, p's < 0.05), than the Stretching group.

CONCLUSIONS

This 12-week Qigong intervention was feasible and potentially efficacious in improving senior prostate cancer survivors' levels of fatigue and distress levels. Future, larger definitive randomized controlled trials are needed to confirm these benefits in older prostate cancer survivors and in racially and ethnically diverse populations.

IMPLICATIONS FOR CANCER SURVIVORS

Qigong may be an effective nonpharmacological intervention for the management of senior prostate cancer survivors' fatigue and distress.

Dysregulation of leukocyte gene expression in women with medication-refractory depression versus healthy non-depressed controls

BACKGROUND

Depressive Disorders (DD) are a great financial and social burden. Females display 70% higher rate of depression than males and more than 30% of these patients do not respond to conventional medications. Thus medication-refractory female patients are a large, under-served, group where new biological targets for intervention are greatly needed.

METHODS

We used real-time quantitative polymerase chain reaction (qPCR) to evaluate mRNA gene expression from peripheral blood leukocytes for 27 genes, including immune, HPA-axis, ion channels, and growth and transcription factors. Our sample included 23 females with medication refractory DD: 13 with major depressive disorder (MDD), 10 with bipolar disorder (BPD). Our comparison group was 19 healthy, non-depressed female controls. We examined differences in mRNA expression in DD vs. controls, in MDD vs. BPD, and in patients with greater vs. lesser depression severity.

RESULTS

DD patients showed increased expression for IL-10, IL-6, OXTR, P2RX7, P2RY1, and TRPV1. BPD patients showed increased APP, CREB1, NFKB1, NR3C1, and SPARC and decreased TNF expression. Depression severity was related to increased IL-10, P2RY1, P2RX1, and TRPV4 expression.

CONCLUSIONS

These results support prior findings of dysregulation in immune genes, and provide preliminary evidence of dysregulation in purinergic and other ion channels in females with medication-refractory depression, and in transcription and growth factors in those with BPD. If replicated in future research examining protein levels as well as mRNA, these pathways could potentially be used to explore biological mechanisms of depression and to develop new drug targets.

The role of oxytocin in familiarization-habituation responses to social novelty

Stress or arousal responses to novel social contexts ease off when individuals get familiar with the social context. In the present study we investigated whether oxytocin is involved in this process of familiarization-habituation as oxytocin is known to increase trust and decrease anxiety. Fifty-nine healthy female subjects took part in the same experimental procedure in two sessions separated by 4 weeks. In the first (novelty) session state trust scores were significantly positively correlated with salivary oxytocin levels while in the second (familiarity) session state trust scores were significantly negatively correlated with salivary oxytocin levels. In a path model oxytocin was associated with increased trust in the novelty session and trust was associated with decreased oxytocin levels in the familiarity session. The results are consistent with the idea that oxytocin decreases stress-to-novelty responses by promoting familiarization to novel social contexts.

Exogenously applied muscle metabolites synergistically evoke sensations of muscle fatigue and pain in human subjects

NEW FINDINGS

What is the central question of this study? Can physiological concentrations of metabolite combinations evoke sensations of fatigue and pain when injected into skeletal muscle? If so, what sensations are evoked? What is the main finding and its importance? Low concentrations of protons, lactate and ATP evoked sensations related to fatigue. Higher concentrations of these metabolites evoked pain. Single metabolites evoked no sensations. This suggests that the combination of an ASIC receptor and a purinergic P2X receptor is required for signalling fatigue and pain. The results also suggest that two types of sensory neurons encode metabolites; one detects low concentrations of metabolites and signals sensations of fatigue, whereas the other detects higher levels of metabolites and signals ache and hot. The perception of fatigue is common in many disease states; however, the mechanisms of sensory muscle fatigue are not understood. In mice, rats and cats, muscle afferents signal metabolite production in skeletal muscle using a complex of ASIC, P2X and TRPV1 receptors. Endogenous muscle agonists for these receptors are combinations of protons, lactate and ATP. Here we applied physiological concentrations of these agonists to muscle interstitium in human subjects to determine whether this combination could activate sensations and, if so, to determine how the subjects described these sensations. Ten volunteers received infusions (0.2 ml over 30 s) containing protons, lactate and ATP under the fascia of a thumb muscle, abductor pollicis brevis. Infusion of individual metabolites at maximal amounts evoked no fatigue or pain. Metabolite combinations found in resting muscles (pH 7.4 + 300 nm ATP + 1 mm lactate) also evoked no sensation. The infusion of a metabolite combination found in muscle during moderate endurance exercise (pH 7.3 + 400 nm ATP + 5 mm lactate) produced significant fatigue sensations. Infusion of a metabolite combination associated with vigorous exercise (pH 7.2 + 500 nm ATP + 10 mm lactate) produced stronger sensations of fatigue and some ache. Higher levels of metabolites (as found with ischaemic exercise) caused more ache but no additional fatigue sensation. Thus, in a dose-dependent manner, intramuscular infusion of combinations of protons, lactate and ATP leads to fatigue sensation and eventually pain, probably through activation of ASIC, P2X and TRPV1 receptors. This is the first demonstration in humans that metabolites normally produced by exercise act in combination to activate sensory neurons that signal sensations of fatigue and muscle pain.

The quality of spouses' social networks contributes to each other's cardiovascular risk

OBJECTIVES

Although the quality of one's own social relationships has been related to cardiovascular morbidity and mortality, whether a partner's social network quality can similarly influence one's cardiovascular risk is unknown. In this study we tested whether the quality of a partner's social networks influenced one's own ambulatory blood pressure (ABP).

METHODS

The quality of 94 couples' social networks was determined using a comprehensive model of relationships that separates out social ties that are sources of positivity(supportive), negativity (aversive), and both positivity and negativity (ambivalent). We then utilized statistical models (actor-partner analyses) that allowed us to separate out the links between one's own social network quality on ABP (actor influences), a partner's social network quality on ABP (partner influences), and a couple's network quality combined on ABP (actor X partner interactions).

RESULTS

Independent of one's own relationship quality, results showed that an individual's ABP was lower if their spouse had more supportive ties, and higher if a spouse had more aversive and ambivalent ties. In addition, couples' networks in combination were associated with higher ABP but only if both had a low number of supportive ties, or a high number of aversive or ambivalent ties.

CONCLUSIONS

These data suggest that the social ties of those we have close relationships with may influence our cardiovascular risk and opens new opportunities to capitalize on untapped social resources or to mitigate hidden sources of social strain.

Antidepressant and neurocognitive effects of isoflurane anesthesia versus electroconvulsive therapy in refractory depression

Background

Many patients have serious depression that is nonresponsive to medications, but refuse electroconvulsive therapy (ECT). Early research suggested that isoflurane anesthesia may be an effective alternative to ECT. Subsequent studies altered drug, dose or number of treatments, and failed to replicate this success, halting research on isoflurane's antidepressant effects for a decade. Our aim was to re-examine whether isoflurane has antidepressant effects comparable to ECT, with less adverse effects on cognition.

Method

Patients with medication-refractory depression received an average of 10 treatments of bifrontal ECT (n = 20) or isoflurane (n = 8) over 3 weeks. Depression severity (Hamilton Rating Scale for Depression-24) and neurocognitive responses (anterograde and retrograde memory, processing speed and verbal fluency) were assessed at Pretreatment, Post all treatments and 4-week Follow-up.

Results

Both treatments produced significant reductions in depression scores at Post-treatment and 4-week Follow-up; however, ECT had modestly better antidepressant effect at follow-up in severity-matched patients. Immediately Post-treatment, ECT (but not isoflurane) patients showed declines in memory, fluency, and processing speed. At Follow-up, only autobiographical memory remained below Pretreatment level for ECT patients, but isoflurane patients had greater test-retest neurocognitive score improvement.

Conclusions

Our data reconfirm that isoflurane has an antidepressant effect approaching ECT with less adverse neurocognitive effects, and reinforce the need for a larger clinical trial.

Specific dimensions of perceived support and ambulatory blood pressure: which support functions appear most beneficial and for whom?

Perceived support has been related to lower cardiovascular morbidity and mortality. However, little is known about the specific functional components of support responsible for such links. We tested if emotional, informational, tangible, and belonging support predicted ambulatory blood pressure (ABP) and interpersonal interactions (e.g., responsiveness), and if such links were moderated by gender. In this study, 94 married couples underwent 12 h of ABP monitoring during daily life which included a night at home with their spouse. They completed a short-form of the interpersonal support evaluation list that provides information on total (global) support, as well as specific dimensions of support. Results revealed that global support scores did not predict ABP during daily life. However, separating out distinct support components revealed that emotional support was a significant predictor of lower ambulatory systolic and diastolic blood pressure, primarily for women. Finally, emotional support predicted greater partner responsiveness and self-disclosure, along with less perceived partner negativity although these results were not moderated by gender. These data are discussed in terms of the importance of considering specific support components and the contextual processes that might influence such links.

Feasibility and acceptability of a Tai Chi Chih randomized controlled trial in senior female cancer survivors

OBJECTIVE

The purpose of this randomized controlled trial (RCT) was to examine the feasibility and acceptability of a Tai Chi Chih (TCC) intervention in senior female cancer survivors with physical functioning limitations, and its effects on health-related quality of life (QOL).

DESIGN

This was a two-armed, parallel group, RCT with 12-weeks of Tai Chi Chih or Health Education Control.

METHODS

Sixty-three senior (M age = 67 years, SD = 7.15) female cancer survivors (83% breast cancer, stages I-III) with physical functioning limitations (SF-12 Health Survey role-physical & physical functioning subscales) were randomized to 12-weeks of TCC or Health Education control (HEC). Primary outcomes were feasibility and acceptability. Secondary outcomes included health-related QOL (SF-36 Health Survey), and participants' qualitative feedback on the intervention.

RESULTS

Retention (TCC = 91%; HEC = 81%) and class attendance (TCC = 79%; HEC = 83%) rates, and satisfaction levels for both study arms were high, but did not significantly differ from one another. At one-week post-intervention, none of the SF-36 scores differed between the TCC and HEC groups. Within-group analyses revealed significant improvements in the mental component summary score in TCC (p = 0.01), but not in HEC. Qualitative analyses indicated that the TCC group felt they received mental and physical benefits, whereas HEC group reported on social support benefits and information received.

CONCLUSION

The TCC intervention was found to be a feasible and acceptable modality for senior female cancer survivors. Future, larger definitive trials are needed to clarify TCC dosage effects on QOL in this vulnerable population.

The impact of oxytocin administration and maternal love withdrawal on event-related potential (ERP) responses to emotional faces with performance feedback

This is the first experimental study on the effect of oxytocin administration on the neural processing of facial stimuli conducted with female participants that uses event-related potentials (ERPs). Using a double-blind, placebo-controlled within-subjects design, we studied the effects of 16 IU of intranasal oxytocin on ERPs to pictures combining performance feedback with emotional facial expressions in 48 female undergraduate students. Participants also reported on the amount of love withdrawal they experienced from their mothers. Vertex positive potential (VPP) and late positive potential (LPP) amplitudes were more positive after oxytocin compared to placebo administration. This suggests that oxytocin increased attention to the feedback stimuli (LPP) and enhanced the processing of emotional faces (VPP). Oxytocin heightened processing of the happy and disgusted faces primarily for those reporting less love withdrawal. Significant associations with LPP amplitude suggest that more maternal love withdrawal relates to the allocation of attention toward the motivationally relevant combination of negative feedback with a disgusted face.

Social relationships and health: is feeling positive, negative, or both (ambivalent) about your social ties related to telomeres?

OBJECTIVES

The quality of one's personal relationships has been linked to morbidity and mortality across different diseases. As a result, it is important to examine more integrative mechanisms that might link relationships across diverse physical health outcomes. In this study, we examine associations between relationships and telomeres that predict general disease risk. These questions are pursued in the context of a more comprehensive model of relationships that highlights the importance of jointly considering positive and negative aspects of social ties.

METHOD

One hundred thirty-six individuals from a community sample (ages 48 to 77 years) completed the social relationships index, which allows a determination of relationships that differ in their positive and negative substrates (i.e., ambivalent, supportive, aversive, indifferent). Telomere length was determined from peripheral blood mononuclear cells via quantitative polymerase chain reaction.

RESULTS

Participants who had a higher number of ambivalent ties in their social networks evidenced shorter telomeres. These results were independent of other relationship types (e.g., supportive) and standard control variables (e.g., age, health behaviors, and medication use). Gender moderated the links between ambivalent ties and telomere length, with these associations seen primarily in women. Follow-up analyses revealed that the links between ambivalent ties and telomeres were primarily due to friendships, parents, and social acquaintances.

CONCLUSION

Consistent with epidemiological findings, these data highlight a novel and integrative biological mechanism by which social ties may affect health across diseases and further suggest the importance of incorporating positivity and negativity in the study of specific relationships and physical health.

Neural responses to infants linked with behavioral interactions and testosterone in fathers

Few fMRI studies have investigated the brain-behavioral basis of parenting in human fathers. Ten fathers were videotaped and gave salivary testosterone samples while interacting with their 2-4 months old infants, and viewed video clips of their own infant and an unfamiliar age-, ethnicity- and sex-matched other infant during an fMRI protocol. Infant stimuli activated a network of prefrontal and subcortical brain regions. Furthermore, a subset of these regions activated significantly more to own (OWN) than other (OTHER) infants. Finally, neural responses to OWN versus OTHER were linked with paternal sensitivity, paternal reciprocity, and testosterone. In sum, our results provide a novel perspective on the links between brain, behavior, and hormones in fathers.

Effects of couple interactions and relationship quality on plasma oxytocin and cardiovascular reactivity: empirical findings and methodological considerations

Cardiovascular reactivity is a potential mechanism underlying associations of close relationship quality with cardiovascular disease. Two models describe oxytocin as another mechanism. The "calm and connect" model posits an association between positive relationship experiences and oxytocin levels and responses, whereas the "tend and befriend" model emphasizes the effects of negative relationship experiences in evoking oxytocin release. In this study of 180 younger couples, relationship quality had a small, marginally significant inverse association with plasma oxytocin levels, and neither positive nor negative couple interactions evoked change in plasma oxytocin. Negative couple interactions evoked significant cardiovascular reactivity, especially among women. Hence, in the largest study of these issues to date, there was little support for key tenets of the "calm and connect" model, and only very modest support for the "tend and befriend" model. However, findings were consistent with the view that CVR contributes to the effects of relationship difficulties on health.

Subliminal activation of social ties moderates cardiovascular reactivity during acute stress

OBJECTIVE

The quality of one's personal relationships has been reliably linked to important physical health outcomes, perhaps through the mechanism of physiological stress responses. Most studies of this mechanism have focused on whether more conscious interpersonal transactions influence cardiovascular reactivity. However, whether such relationships can be automatically activated in memory to influence physiological processes has not been determined. The primary aims of this study were to examine whether subliminal activation of relationships could influence health-relevant physiological processes and to examine this question in the context of a more general relationship model that incorporates both positive and negative dimensions.

METHOD

We randomly assigned participants to be subliminally primed with existing relationships that varied in their underlying positivity and negativity (i.e., indifferent, supportive, aversive, ambivalent). They then performed acute psychological stressors while cardiovascular and self-report measures were assessed.

RESULTS

Priming negative relationships was associated with greater threat, lower feelings of control, and higher diastolic blood pressure reactivity during stress. Moreover, priming relationships high in positivity and negativity (ambivalent ties) was associated with the highest heart rate reactivity and greatest respiratory sinus arrhythmia decreases during stress. Exploratory analyses during the priming task itself suggested that the effects of negative primes on biological measures were prevalent across tasks, whereas the links to ambivalent ties was specific to the subsequent stressor task.

CONCLUSIONS

These data highlight novel mechanisms by which social ties may impact cardiovascular health, and further suggest the importance of incorporating both positivity and negativity in the study of relationships and physical health.

Gene expression alterations at baseline and following moderate exercise in patients with Chronic Fatigue Syndrome and Fibromyalgia Syndrome

OBJECTIVES

To determine mRNA expression differences in genes involved in signalling and modulating sensory fatigue, and muscle pain in patients with chronic fatigue syndrome (CFS) and fibromyalgia syndrome (FM) at baseline, and following moderate exercise.

DESIGN

Forty-eight patients with CFS only, or CFS with comorbid FM, 18 patients with FM that did not meet criteria for CFS, and 49 healthy controls underwent moderate exercise (25 min at 70% maximum age-predicted heart rate). Visual-analogue measures of fatigue and pain were taken before, during and after exercise. Blood samples were taken before and 0.5, 8, 24 and 48 h after exercise. Leucocytes were immediately isolated from blood, number coded for blind processing and analyses and flash frozen. Using real-time, quantitative PCR, the amount of mRNA for 13 genes (relative to control genes) involved in sensory, adrenergic and immune functions was compared between groups at baseline and following exercise. Changes in amounts of mRNA were correlated with behavioural measures and functional clinical assessments.

RESULTS

No gene expression changes occurred following exercise in controls. In 71% of patients with CFS, moderate exercise increased most sensory and adrenergic receptor's and one cytokine gene's transcription for 48 h. These postexercise increases correlated with behavioural measures of fatigue and pain. In contrast, for the other 29% of patients with CFS, adrenergic α-2A receptor's transcription was decreased at all time-points after exercise; other genes were not altered. History of orthostatic intolerance was significantly more common in the α-2A decrease subgroup. FM-only patients showed no postexercise alterations in gene expression, but their pre-exercise baseline mRNA for two sensory ion channels and one cytokine were significantly higher than controls.

CONCLUSIONS

  At least two subgroups of patients with CFS can be identified by gene expression changes following exercise. The larger subgroup showed increases in mRNA for sensory and adrenergic receptors and a cytokine. The smaller subgroup contained most of the patients with CFS with orthostatic intolerance, showed no postexercise increases in any gene and was defined by decreases in mRNA for α-2A. FM-only patients can be identified by baseline increases in three genes. Postexercise increases for four genes meet published criteria as an objective biomarker for CFS and could be useful in guiding treatment selection for different subgroups.

Salivary levels of oxytocin remain elevated for more than two hours after intranasal oxytocin administration

OBJECTIVE

This is the first study investigating whether levels of oxytocin in saliva remained elevated after intranasal oxytocin administration for the duration of an experiment (in which neurobehavioral effects of oxytocin were observed) taking more than two hours.

METHODS

Oxytocin levels were measured in saliva samples collected from 57 female participants right before (T0), approximately 1¼ h (T1), and approximately 2¼ h (T2) after intranasal administration of 16 IU of oxytocin or a placebo, using a double-blind, within-subjects design.

RESULTS

Average levels of oxytocin did not differ between conditions before use of the nasal spray, markedly increased only after oxytocin administration, and were still elevated after 2¼ h.

CONCLUSION

Salivary levels of oxytocin remained persistently elevated over the course of our experiment, i.e. for more than two hours after intranasal oxytocin administration and over a time-period in which neurobehavioral effects of oxytocin are commonly observed. This suggests that salivary concentrations may be a valuable biomarker for oxytocin, and may help to explain its effects on brain activity, information processing, and behavior.

The influence of depressive symptomatology and perceived stress on plasma and salivary oxytocin before, during and after a support enhancement intervention

Oxytocin (OT) activity increases in response to stress as well as to warm social contact. Subclinical depression is associated with higher stress but less reward from social contacts. The present investigation was intended to examine whether husbands and wives with high depressive symptomatology scores have increased plasma and salivary OT that may be mediated partly by higher perceived stress, and also to assess whether an intervention to convey partner support through "warm touch" may reduce effects of depressive symptoms on OT. In this study, 34 healthy married couples (n=68) ages 20-39 provided self reports of depressive symptoms (CESD) and stress (Perceived Stress Scale) before being randomly assigned to a 4-week intervention study enhancing partner support through "warm touch", or to a "behavior monitoring" control group. Plasma oxytocin levels were obtained pre- and post-intervention, while salivary oxytocin was taken at home during week 1 and week 4. Results revealed that subjects with higher depressive symptoms scores had higher plasma OT levels at pre-intervention, and higher salivary OT levels at home during week 1 (p<.05). Plasma OT results were moderated by gender such that plasma OT levels were highest among females high in depressive symptomology. Higher perceived stress was also linked to both higher depressive symptomatology (r=+65, p<.0001) and plasma OT (p< .05) and a significant mediator. During the intervention, salivary OT remained elevated among subjects high in depressive symptomatology in the control group but not the intervention group. At post-intervention, plasma OT levels in subjects with vs. without depressive symptomatology no longer differed. Results indicate that subclinical depression is associated with elevated plasma and salivary OT levels, which may be mediated in part by increased stress. OT differences linked to subclinical depression were minimized by the warm touch intervention.

Plasma oxytocin is related to lower cardiovascular and sympathetic reactivity to stress

In addition to known reproductive and social affiliation functions, oxytocin (OT) has been identified as a cardiovascular hormone. OT synthesis and receptors are found in cardiac and vascular tissue. Animal studies suggest that OT activates an 'anti-stress' response that reduces cardiovascular and neuroendocrine stress reactivity. We tested 28 early postpartum mothers, obtaining multiple blood samples for OT, the sympathetic marker, norepinephrine (NE), and the lactation hormone, prolactin, while monitoring their cardiovascular responses to two stressors: public speaking and forehead cold pressor. Although plasma OT did not increase reliably from pre-stress levels during stressors, greater overall OT level was related to greater vasodilation and cardiac stroke volume responses to both tasks, to reduction in heart rate to the cold pressor, as well as to lower plasma NE and higher prolactin levels. In contrast, higher NE was linked to increases in heart rate and decreases in stroke volume. These data support a cardioprotective role for OT, which may influence the magnitude and hemodynamic determinants of cardiovascular stress responses.

Severity of symptom flare after moderate exercise is linked to cytokine activity in chronic fatigue syndrome

Chronic fatigue syndrome (CFS) patients often report symptom flare (SF) for >24 h after moderate exercise (post-ex). We hypothesized that SF is linked to increases in circulating cytokines and CD40 Ligand (CD40L). In 19 CFS patients and 17 controls, mental and physical fatigue and pain symptom ratings were obtained together with serum for 11 cytokines and CD40L before and at 0.5, 8, 24, and 48 h post-ex. Before exercise, CFS had lower CD40L (p<.05) but similar cytokines versus controls. In subgroups based on SF at 48 h, high SF patients (n=11) increased in IL-1beta, IL-12, IL-6, IL-8, IL-10, and IL-13 (p<.05) 8 h post-ex. Low SF patients (n=8) showed post-ex decreases in IL-10, IL-13, and CD40L, and controls decreased in IL-10, CD40L, and TNFalpha (p<.05). Thus, in CFS, cytokine activity may vary directly with SF, which may explain prior inconsistent findings.

An investigation of plasma and salivary oxytocin responses in breast- and formula-feeding mothers of infants

Oxytocin (OT) is a peptide increasingly studied in relation to human social interactions, affiliation, and clinical disorders. Studies are constrained by use of invasive blood draws and would benefit from a reliable salivary OT assay. Our goals were to examine feasibility of salivary OT measurement, compare salivary to plasma OT responses in 12 breast- and 8 formula-feeding mothers, and assess the degree of correlation between plasma and salivary OT. Using a commercial EIA kit, we measured OT in 5 saliva and 7 plasma samples in a protocol designed to elicit changes in OT (Rest, Infant Interaction, Stress, Feeding). Breast-feeders had higher OT levels than formula-feeders across all conditions in plasma (+36%) and saliva (+23%). OT levels and ranges were similar in saliva and plasma, with slightly greater variance in saliva. Concurrently sampled plasma and salivary OT were correlated at end of Baseline Rest (r=+.59, p=.022) and Post-Stress Recovery (r=+.59, p=.025). These data suggest that salivary OT assay is feasible, and will be of value where plasma samples are not possible. Validation with larger samples is needed.

Moderate exercise increases expression for sensory, adrenergic, and immune genes in chronic fatigue syndrome patients but not in normal subjects

Chronic fatigue syndrome (CFS) is characterized by debilitating fatigue, often accompanied by widespread muscle pain that meets criteria for fibromyalgia syndrome (FMS). Symptoms become markedly worse after exercise. Previous studies implicated dysregulation of the sympathetic nervous system (SNS), and immune system (IS) in CFS and FMS. We recently demonstrated that acid sensing ion channel (probably ASIC3), purinergic type 2X receptors (probably P2X4 and P2X5) and the transient receptor potential vanilloid type 1 (TRPV1) are molecular receptors in mouse sensory neurons detecting metabolites that cause acute muscle pain and possibly muscle fatigue. These molecular receptors are found on human leukocytes along with SNS and IS genes. Real-time, quantitative PCR showed that 19 CFS patients had lower expression of beta-2 adrenergic receptors but otherwise did not differ from 16 control subjects before exercise. After a sustained moderate exercise test, CFS patients showed greater increases than control subjects in gene expression for metabolite detecting receptors ASIC3, P2X4, and P2X5, for SNS receptors alpha-2A, beta-1, beta-2, and COMT and IS genes for IL10 and TLR4 lasting from 0.5 to 48 hours (P < .05). These increases were also seen in the CFS subgroup with comorbid FMS and were highly correlated with symptoms of physical fatigue, mental fatigue, and pain. These new findings suggest dysregulation of metabolite detecting receptors as well as SNS and IS in CFS and CFS-FMS.

PERSPECTIVE

Muscle fatigue and pain are major symptoms of CFS. After moderate exercise, CFS and CFS-FMS patients show enhanced gene expression for receptors detecting muscle metabolites and for SNS and IS, which correlate with these symptoms. These findings suggest possible new causes, points for intervention, and objective biomarkers for these disorders.

Adrenergic dysregulation and pain with and without acute beta-blockade in women with fibromyalgia and temporomandibular disorder

In patients with fibromyalgia syndrome (FMS) and temporomandibular disorder (TMD), stress and pain may chronically enhance sympathetic activity, altering cardiovascular responses and worsening pain. This study examined cardiovascular, epinephrine (EPI), norepinephrine (NE), cortisol and clinical pain responses in 54 female patients with these disorders and 34 controls. In a subsample of 10 FMS, 10 TMD patients and 16 controls, using a counterbalanced, double-blind, crossover design, the same responses were assessed after intravenous administration of low dose propranolol vs placebo. Testing included baseline, postural, speech and ischemic pain stressors. FMS patients showed lesser heart rate (HR) increases to posture challenge but greater blood pressure (BP) increases to postural and speech tasks than controls, as well as higher overall BP and greater total vascular resistance (TVR) than TMDs or controls. TMDs showed higher overall cardiac output and lower TVR than controls. Both FMS and TMD groups showed lower baseline NE than controls, and TMDs showed lower overall EPI and NE levels. Group differences in HR, EPI and NE were abolished after propranolol although BP, CO and TVR differences persisted. In both FMS and TMD, the number of painful body sites and ratings of total clinical pain obtained 4 times during each session were significantly lower after beta-blockade vs placebo.

PERSPECTIVE

These findings support the hypothesis that both FMS and TMD may frequently involve dysregulation of beta-adrenergic activity that contributes to altered cardiovascular and catecholamine responses and to severity of clinical pain. Acute treatment with low-dose propranolol led to short-term improvement in all these domains.

Brain activation in multiple sclerosis: a BOLD fMRI study of the effects of fatiguing hand exercise

Background

Multiple sclerosis (MS) patients experience fatigue as a chronic symptom that decreases quality of life. Commonly, fatigue in MS patients is manifested as decreased motor function during or after physical activity and is associated with changes in brain metabolism.

Objective

To determine brain activation patterns in MS patients and healthy controls during a simple motor task before and after fatiguing hand-grip exercise.

Methods

Functional magnetic resonance imaging (fMRI) scans were conducted on 10 MS patients and 13 healthy controls during 4-finger flexion and extension in rested and fatigued states.

Results

Before the fatigue protocol, MS patients had greater activation in the contralateral primary motor cortex, insula, and cingulate gyrus than controls. Following fatiguing exercise, controls showed increased activation of precentral gyrus and insula while patients did not show any activation increases and actually decreased activity to the insula.

Conclusion

Results indicate that before fatiguing exercise, MS patients marshaled more brain activation compared to controls, which may represent functionally adaptive changes in response to demyelination. This increased activation may suggest that patients require more effort to perform even simple motor tasks, possibly because peripheral or central signals for fatigue are chronically enhanced. When fatigued further by muscle contraction, brain activation cannot be further increased.

Stress and placental resistance measured by Doppler ultrasound in early and mid-pregnancy

OBJECTIVES

To examine the association between self reports and biomarkers of stress and placental resistance (measured by Doppler ultrasound of the uterine and umbilical arteries), to determine if restriction of blood flow to the placenta is a mechanism by which stress might affect health during pregnancy.

METHODS

Eight hundred and seventy-two women had ultrasound examinations of the uterine artery at 15-19 weeks' gestation and the uterine and umbilical arteries at 24-29 weeks, and resistance and pulsatility indices were calculated. Psychosocial stress was measured by telephone interview and self-administered questionnaire using several validated tools twice during the pregnancy. Cortisol and corticotropin-releasing hormone (CRH) were measured twice during the pregnancy. Linear and hierarchical models were used to examine the relationships among reported stress, stress hormones and placental Doppler indices.

RESULTS

The umbilical artery resistance index was higher in younger women, those with less education, those who were single and those who smoked. The uterine artery pulsatility index was higher in women with pre-eclampsia, those living alone, those with high body mass index, and those who gained the least weight during pregnancy. A higher CRH level was associated with small increases in uterine artery pulsatility and umbilical artery resistance indices. Psychosocial measures of stress were not consistently associated with higher placental resistance.

CONCLUSIONS

Increased CRH levels may be associated with increased placental resistance. Otherwise, these findings do not support the hypothesis that restriction of blood flow to the fetus is a major mechanism by which stress affects infant health.

Ethnicity is associated with alterations in oxytocin relationships to pain sensitivity in women

It is well established that African Americans (AA) experience greater pain associated with a variety of clinical conditions, and greater pain sensitivity to experimental pain tasks relative to non-Hispanic Whites (W). Notably, African Americans do not show the same relationships involving endogenous pain regulatory mechanisms and pain sensitivity documented in Caucasians, including positive associations between blood pressure, norepinephrine, cortisol and greater pain tolerance.

OBJECTIVES

The purpose of this study was to examine the relationship between plasma oxytocin (OT) and pain sensitivity and to explore the relation of OT to other factors known to influence pain perception.

DESIGN

OT concentration and sensitivity to ischemic, cold pressor, and thermal pain tasks were assessed in African American (n=25) and non-Hispanic White (n=23) pre-menopausal women.

RESULTS

African American women demonstrated significantly lower pain tolerance across tasks compared with Whites (F(1,46)=6.31, p=0.0156) and also exhibited lower plasma OT levels (AA: 3.90, W: 7.05 pg/mL; p=0.0014). Greater OT levels were correlated with greater tolerance to ischemic pain (r=0.36, p=0.013) and accounted for a marginally significant portion of the ethnic difference in ischemic pain tolerance (B=+0.29, p=0.06). Greater OT was also correlated with greater tolerance of cold pressor pain (r=0.31, p=0.03); however, this association was no longer seen after the variance due to ethnicity was accounted for.

CONCLUSION

These data suggest that reduced oxytocinergic function may be one of multiple biological factors contributing to the greater sensitivity to experimental ischemic pain, and to the greater burden of some types of clinical pain experienced by African Americans compared with Whites.

Persistent alterations in biological profiles in women with abuse histories: influence of premenstrual dysphoric disorder

OBJECTIVE

To examine dysregulation in biological measures associated with histories of abuse in women and whether women with premenstrual dysphoric disorder (PMDD) differ in their dysregulation.

DESIGN

Twenty-five women meeting prospective criteria for PMDD and 42 non-PMDD controls underwent structured interview to determine abuse histories and lifetime Axis I diagnoses, excluding those with current Axis I disorders or using medications.

MAJOR OUTCOME MEASURES

Plasma cortisol and norepinephrine (NE), heart rate (HR), blood pressure (BP), and vascular resistance index (VRI) were assessed at rest and in response to mental stress.

RESULTS

A greater proportion of PMDD women had prior abuse compared with non-PMDD women. Regardless of PMDD status, all abused women had lower plasma NE and higher HRs and tended to have lower plasma cortisol at rest and during stress. Abused women also reported more severe daily emotional and physical symptoms. Greater VRI and BP at rest and during stress were seen only in PMDD women with abuse.

CONCLUSION

There is persistent dysregulation in stress-responsive systems in all abused women that cannot be accounted for by current psychiatric illness or medications, and PMDD women may be differentially more vulnerable to the impact of abuse on measures reflecting alpha-adrenergic receptor function.

Associations of abdominal fat with perceived racism and passive emotional responses to racism in African American women

OBJECTIVES

An excess in abdominal fat may predispose African American women to chronic health conditions such as diabetes and cardiovascular disease. Because stress may increase body fat in the center-body region, we used the waist-to-hip ratio (WHR) to examine associations between excess abdominal fat and perceived racism (a chronic stressor) and daily stress. Passive emotional responses to perceived racism, hypothesized to have particularly adverse effects, were also examined.

METHODS

We controlled for body mass index in multiple logistic regression models among 447 African American women who completed a telephone interview on perceived racism.

RESULTS

Passive emotional responses were not related to WHR (odds ratio [OR]=1.4; 95% confidence interval [CI]=0.8, 2.4). High perceived racism was associated with a low WHR in this population (OR=0.4; 95% CI=0.3, 0.8). However, high daily stress was related to a high WHR (OR=2.7; 95% CI=1.1, 6.7).

CONCLUSIONS

Findings support an association between daily stress and WHR but do not support our hypothesis that passive emotional responses to perceived racism increase abdominal fat. Further study of the stress physiology of perceived racism in African American women is warranted.

Ethnic differences in allopregnanolone concentrations in women during rest and following mental stress

The neuroactive steroid allopregnanolone (ALLO) is stress sensitive, negatively modulates the HPA axis, and has been implicated in mood disorders. We examined ethnic differences in plasma ALLO at rest and following mental stress in African American (AA) men (n = 21) and women (n = 24) and non-Hispanic White men (n = 24) and women (n = 25). Overall, AA women had lower ALLO concentrations than non-Hispanic White women (p < .05), especially following mental stress (p < .01). Only 20% of AA women showed the expected stress-induced increase in ALLO compared with 59% of non-Hispanic White women (p < .01). No ethnic differences were seen in men. For both ethnic groups, poststress ALLO was negatively correlated with poststress cortisol (p < .05). Results are interpreted to reflect dysregulation in ALLO mechanisms in AA women and may have implications for ethnic differences in mood disorders.

Associations of histories of depression and PMDD diagnosis with allopregnanolone concentrations following the oral administration of micronized progesterone

Twenty-three women with premenstrual dysphoric disorder (PMDD) and 29 non-PMDD controls were compared for plasma progesterone (P) and its neuroactive steroid metabolite allopregnanolone (ALLO), as well as the ALLO/P ratio following the double-blind, placebo controlled administration of 300 mg oral micronized progesterone. Approximately half of each group had prior depression (DEP) (13 PMDD, 12 non-PMDD), though all were free of current depression. Progesterone and ALLO were sampled 160, 190, 225, and 255 min after progesterone administration. Changes over time in plasma concentrations and the ALLO/P ratio were assessed using area under the curve analyses. Women with prior DEP had lower ALLO levels (p=0.05) and marginally lower P levels (p<0.07) following progesterone administration compared to never depressed women, and this was especially evident in the non-PMDD women (p<0.01). PMDD women with no prior DEP had higher pre-progesterone ALLO/P ratios than all other groups (Ps<0.05) and higher ratios than the never depressed, non-PMDD women following oral progesterone (p<0.05). Results could not be accounted for by group differences in steroid hormone binding protein concentrations. For all women, progesterone administration was associated with increased confusion, fatigue, and with reduced confidence (Ps<0.01), even after controlling for placebo-associated mood change. These results suggest a persistent effect of prior DEP on P and ALLO concentrations following oral progesterone and that PMDD women, especially those with no prior DEP, may have alterations in the metabolic pathways underlying the conversion of P to ALLO.

Patterns of salivary cortisol secretion in pregnancy and implications for assessment protocols

Cortisol is used in research as a biomarker of psychological stress. Logistical considerations argue for collecting as few samples as possible, balanced against diurnal rhythms and intra-individual variations. 100 pregnant women gave five saliva samples a day for 3 days, at waking, 30 min after waking, and 11:00 a.m., 5:00 p.m., and 9:00 p.m. Timing of collection was confirmed by monitors. Another sample was taken during a clinic visit. Using the 15 measures as the gold standard, correlations and mean area under the curve (AUC) were compared with subsets and the single clinic sample to evaluate alternate collection protocols. Five samples in 1 day, or protocols involving morning and night samples, had the highest correlations with mean AUC (correlation coefficient ranging from 0.82 to 0.88). Standardizing the clinic measurement to a single time of day did not substantially improve correlations with mean AUC. Correlations with measures of reported stress were also not strong.

Orthostatic hypotension predicts mortality in middle-aged adults: the Atherosclerosis Risk In Communities (ARIC) Study

BACKGROUND

An association between orthostatic hypotension (OH) and mortality has been reported, but studies are limited to older adults or high-risk populations.

METHODS AND RESULTS

We investigated the association between OH (a decrease of 20 mm Hg in systolic blood pressure or a decrease of 10 mm Hg in diastolic blood pressure on standing) and 13-year mortality among middle-aged black and white men and women from the Atherosclerosis Risk in Communities Study (1987-1989). At baseline, 674 participants (5%) had OH. All-cause mortality was higher among those with (13.7%) than without (4.2%) OH. After we controlled for ethnicity, gender, and age, the hazard ratio (HR) for OH for all-cause mortality was 2.4 (95% confidence interval [CI], 2.1 to 2.8). Adjustment for risk factors for cardiovascular disease and mortality and selected health conditions at baseline attenuated but did not completely explain this association (HR = 1.7; 95% CI, 1.4 to 2.0). This association persisted among subsets that (1) excluded those who died within the first 2 years of follow-up and (2) were limited to those without coronary heart disease, cancer, stroke, diabetes, hypertension, or fair/poor perceived health status at baseline. In analyses by causes of death, a significant increased hazard of death among those with versus without OH persisted after adjustment for risk factors for cardiovascular disease (HR = 2.0; 95% CI, 1.6 to 2.7) and other deaths (HR = 2.1; 95% CI, 1.6 to 2.8) but not for cancer (odds ratio = 1.1; 95% CI, 0.8 to 1.6).

CONCLUSIONS

OH predicts mortality in middle-aged adults. This association is only partly explained by traditional risk factors for cardiovascular disease and overall mortality.

Dietary sodium restriction alters postprandial ghrelin: implications for race differences in obesity

OBJECTIVES

To examine the effect of sodium restriction on the appetite-stimulating hormone, ghrelin, as a function of race, salt sensitivity, and obesity.

DESIGN

PARTICIPANTS completed two 4-day outpatient dietary interventions (moderate vs low sodium), and blood samples were drawn two hours after a controlled test meal under both conditions.

SETTING

A university research laboratory and affiliated General Clinical Research Center.

PARTICIPANTS

37 women (18 Black, 19 White) and 18 men (9 Black, 9 White), aged 36-63 years.

MEASURES

Cardiovascular function (blood pressure, heart rate, impedance-derived indices of cardiac output and peripheral resistance) was measured after a 20-minute rest before each test meal. Blood was drawn by intravenous forearm catheter two hours after each test meal and later assayed for ghrelin, leptin, and norepinephrine.

RESULTS

After four days of sodium restriction, postprandial ghrelin increased in White men and women and Black men but decreased in Black women. Salt sensitivity, but not obesity, was also related to ghrelin response during sodium restriction; postprandial ghrelin tended to increase among salt-sensitive subjects during salt restriction but decrease among salt-resistant subjects during salt restriction.

CONCLUSIONS

Satiety hormone dysregulation may play a role in: 1) the heightened obesity-related morbidity among Black women, in particular; 2) adherence to sodium-restricted diets; and 3) race differences in behavioral weight-loss interventions that include sodium restriction.

Social correlates of the chronic stress of perceived racism among Black women

OBJECTIVES

This study describes the perceptions of racism, passive and active responses to this psychosocial stressor, and it examines socioeconomic correlates of perceived racism in an economically diverse population of Black women.

METHODS

The Telephone-Administered Perceived Racism Scale was administered to 476 Black women, aged 36 to 53 years, who were randomly selected from a large health plan.

RESULTS

The percentage of respondents who reported personally experiencing racism in the past five years ranged from 66% to 93%, depending on the specific item asked. When respondents were asked about racism toward Blacks as a group, perceptions of racism were even higher. For example, 68% "agreed" or "strongly agreed" that they had personally experienced being followed or watched while shopping because of their race, and 93% reported that Blacks in general experience this form of discrimination. Strong emotional responses to racism were often reported, and though more respondents (41%) reported experiencing very strong active emotions including anger, a substantial group (16%) reported experiencing very strong passive emotions such as powerlessness. Higher education was associated with higher perceived racism, while growing up in a middle-income or well-off family was associated with lower perceived racism and reduced likelihood of passive responses to racism.

CONCLUSIONS

The high prevalence of perceived racism in this study population warrants further examination of this stressor as a potential determinant of racial health disparities. Higher education and income do not appear to protect women from experiencing racism and feeling hopeless or powerless in response.