Publications by authors named "Jan Houtveen"

33 Publications

Changed dynamic symptom networks after a self-compassion training in patients with somatic symptom disorder: A multiple single-case pilot project.

J Psychosom Res 2022 Mar 17;154:110724. Epub 2022 Jan 17.

Altrecht Psychosomatic Medicine, Zeist, the Netherlands; Utrecht University, Department of Psychology, Utrecht, the Netherlands.

Objective: Pre-to-post mean group differences of intermittently assessed generic outcome variables may not capture all relevant treatment-related changes in individual patients with somatic symptom disorder (SSD). Aim of this multiple single-case observational pilot project was to find out whether the Experience Sampling Method (ESM) and dynamic symptom networks may offer new opportunities in evaluating treatment outcomes for individual patients with SSD.

Methods: Patients with SSD (N = 6 in study 1, N = 7 in study 2) received a self-compassion training in a tertiary care mental health expert center. Using a single-case pre-post treatment observational design, intensive longitudinal data were collected with ESM. A brief questionnaire was presented via the patient's smartphone three times per day for 16 weeks before, during and after the training in study 1, and for 5 weeks before and 5 weeks after the training in study 2. Eleven questions comprised somatic symptoms, functional disability, stress, self-compassion, and acceptance of affect; three personalized questions comprised self-chosen affects and an additional symptom.

Results: Sufficient observations for means and network comparison were obtained for 11 and 10 patients, respectively. After the training, self-compassion was significantly increased in 10 patients, functional disability, stress and affect improved in 6 patients, and (although not a treatment goal) somatic symptoms decreased in 6 patients. Dynamic symptom networks significantly changed in 5 patients.

Conclusion: Patient-specific changes in means and dynamic symptom networks were observed after self-compassion training. In future clinical trials, single-case ESM may offer new opportunities to evaluate treatment outcomes in patients with SSD.
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http://dx.doi.org/10.1016/j.jpsychores.2022.110724DOI Listing
March 2022

Internet and smartphone-based ecological momentary assessment and personalized advice (PROfeel) in adolescents with chronic conditions: A feasibility study.

Internet Interv 2021 Sep 20;25:100395. Epub 2021 Apr 20.

Department of Pediatrics, Wilhelmina Children's Hospital, University Medical Center Utrecht, Utrecht University, Utrecht, the Netherlands.

Objective: Growing up with a chronic disease comes with challenges, such as coping with fatigue. Many adolescents are severely fatigued, though its associated factors exhibit considerable interpersonal and longitudinal variation. We assessed whether PROfeel, a combination of a smartphone-based ecological momentary assessment (EMA) method using the internet, followed by a face-to-face dialogue and personalized advice for improvement of symptoms or tailor treatment based on a dynamic network analysis report, was feasible and useful.

Study Design: Feasibility study in fatigued outpatient adolescents 12-18 years of age with cystic fibrosis, autoimmune disease, post-cancer treatment, or with medically unexplained fatigue. Participants were assessed at baseline to personalize EMA questions. EMA was conducted via smartphone notifications five times per day for approximately six weeks. Hereby, data was collected via the internet. The EMA results were translated into a personalized report, discussed with the participant, and subsequently translated into a personalized advice. Afterwards, semi-structured interviews on feasibility and usefulness were held.

Results: Fifty-seven adolescents were assessed (mean age 16.2 y ± 1.6, 16% male). Adolescents deemed the smartphone-based EMA feasible, with the app being used for an average of 49 days. Forty-two percent of the notifications were answered and 85% of the participants would recommend the app to other adolescents. The personalized report was deemed useful and comprehensible and 95% recognized themselves in the personalized report, with 64% rating improved insight in their symptoms and subsequent steps towards an approach to reduce one's fatigue as good or very good.

Conclusions: PROfeel was found to be highly feasible and useful for fatigued adolescents with a chronic condition. This innovative method has clinical relevance through bringing a patient's daily life into the clinical conversation.
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http://dx.doi.org/10.1016/j.invent.2021.100395DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8131314PMC
September 2021

Ecological momentary assessment study of exposure to radiofrequency electromagnetic fields and non-specific physical symptoms with self-declared electrosensitives.

Environ Int 2019 10 6;131:104948. Epub 2019 Jul 6.

Centre for Sustainability, Environment and Health, National Institute for Public Health and the Environment (RIVM), PO Box 1, 3720 BA Bilthoven, the Netherlands.

The main objective of the study is to determine if non-specific physical symptoms (NSPS) in people with self-declared sensitivity to radiofrequency electromagnetic fields (RF EMF) can be explained (across subjects) by exposure to RF EMF. Furthermore, we pioneered whether analysis at the individual level or at the group level may lead to different conclusions. By our knowledge, this is the first longitudinal study exploring the data at the individual level. A group of 57 participants was equipped with a measurement set for five consecutive days. The measurement set consisted of a body worn exposimeter measuring the radiofrequency electromagnetic field in twelve frequency bands used for communication, a GPS logger, and an electronic diary giving cues at random intervals within a two to three hour interval. At every cue, a questionnaire on the most important health complaint and nine NSPS had to be filled out. We analysed the (time-lagged) associations between RF-EMF exposure in the included frequency bands and the total number of NSPS and self-rated severity of the most important health complaint. The manifestation of NSPS was studied during two different time lags - 0-1 h, and 1-4 h - after exposure and for different exposure metrics of RF EMF. The exposure was characterised by exposure metrics describing the central tendency and the intermittency of the signal, i.e. the time-weighted average exposure, the time above an exposure level or the rate of change metric. At group level, there was no statistically significant and relevant (fixed effect) association between the measured personal exposure to RF EMF and NSPS. At individual level, after correction for multiple testing and confounding, we found significant within-person associations between WiFi (the self-declared most important source) exposure metrics and the total NSPS score and severity of the most important complaint in one participant. However, it cannot be ruled out that this association is explained by residual confounding due to imperfect control for location or activities. Therefore, the outcomes have to be regarded very prudently. The significant associations were found for the short and the long time lag, but not always concurrently, so both provide complementary information. We also conclude that analyses at the individual level can lead to different findings when compared to an analysis at group level.
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http://dx.doi.org/10.1016/j.envint.2019.104948DOI Listing
October 2019

Experimental pressure-pain assessments: Test-retest reliability, convergence and dimensionality.

Scand J Pain 2012 Jan 1;3(1):31-37. Epub 2012 Jan 1.

Department of Clinical and Health Psychology, Faculty of Social Sciences, Utrecht University, Utrecht, The Netherlands.

Introduction Experimental pain studies can provide unique insight into the dimensions of pain and into individual differences in pain responsiveness by controlling different aspects of pain-eliciting stimuli and pain measures. In experimental pain studies, pain responsiveness can be assessed as pain threshold, pain tolerance or pain ratings. The test-theoretical qualities of these different measures, however, have not yet been completely documented. In the current study, several of these qualities were investigated in a pain experiment applying different algometric techniques. The objective of the study was to investigate the reliability (test-retest) and the convergent validity (correspondence) of the different methods found in the literature of measuring pressure-pain threshold, and the interrelationship between pressure-pain threshold, pressure-pain tolerance, and pressure-pain ratings. Methods Sixty-six healthy female subjects were enrolled in the study. All pressure stimuli were applied by a trained investigator, using a digital algometer with a 1 cm2 rubber tip. Pressure-pain thresholds were assessed repeatedly on six different body points (i.e. left and right calf one third of total calf muscle length below the popliteal space), the lower back (5 cm left and right from the L3), and left and right forearm (thickest part of brachioradialis muscle). Next, pressure-pain tolerance was measured on the thumbnail of the non-dominant hand, followed by rating affective and sensory components (on visual analogue scales) of a stimulus at tolerance level. Last, affective and sensory ratings were obtained for two pressure intensities. Results With intraclass correlations above .75 for pain responses per body point, test-retest reliability was found to be good. However, values obtained from all first measurements were significantly higher as compared with the two succeeding ones. Convergent validity of pain thresholds across different body points was found to be high for all combinations assessed (Cronbach's alpha values >.80), but the highest for bilateral similar body parts (>.89). Finally, principal components analysis including measures of threshold, tolerance and pain ratings yielded a three-factor solution that explained 81.9% of the variance: Moderate-level stimulus appraisal & pain tolerance; Pain threshold; Tolerance-level stimulus appraisal. Conclusion and implications Findings of the current study were used to formulate recommendations for future algometric pain studies. Concerning pressure-pain threshold, it is recommended to exclude first measurements for every body point from further analyses, as these measurements were found to be consistently higher compared with the following measurements. Further, no more than two consecutive measurements (after the first measurement) are needed for a reliable mean threshold value per body point. When combining threshold values of several body points into one mean-aggregated threshold value, we suggest to combine bilateral similar points, as convergent validity values were highest for these combinations. The three-factor solution that was found with principal components analyses indicates that pressure-pain threshold, subjective ratings of moderate intensity stimuli, and subjective ratings of the maximum (tolerance) intensity are distinct aspects of pain responsiveness. It is therefore recommended to include a measure of each of these three dimensions of pain when assessing pressure pain responsiveness. Some limitations of our study are discussed.
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http://dx.doi.org/10.1016/j.sjpain.2011.10.003DOI Listing
January 2012

A concept mapping study on perpetuating factors of functional somatic symptoms from clinicians' perspective.

Gen Hosp Psychiatry 2017 Jan - Feb;44:51-60. Epub 2016 Oct 29.

University of Groningen, University Medical Center Groningen, Interdisciplinary Center Psychopathology and Emotion regulation, Groningen, The Netherlands.

Objective: The aim of this concept mapping study was to identify the structure and alleged importance of perpetuating factors of functional somatic symptoms (FSS) from the perspective of professionals. Further, we examined to which extent these factors have been addressed in scientific literature.

Methods: Ninety-nine perpetuating factors were sorted with respect to content using a card-sorting task by 61 experienced clinicians (62.3% psychologists, 75.4% female, mean age: 45.7 [SD: 10.6] years, mean duration of experience in treating FSS patients: 10.5 [SD: 7.6] years). These factors had been derived from in-depth interviews with 12 clinicians, with extensive experience in treating FSS. Thirty-eight clinicians rated the importance of the 99 factors on a scale ranging from 1 ('not important at all') to 10 ('extremely important').

Results: Hierarchical cluster analysis revealed three overarching domains of perpetuating factors: 'Hypochondria', 'Social and relational problems' and 'Symptom-related emotions and habits'. These domains comprised 16 clusters, which were rated on importance between 6.1, 'Adverse physical factors and counterproductive lifestyle', and 7.8, 'Frustration and despair regarding the symptoms'. All clusters have been addressed in scientific literature.

Conclusions: This study revealed an encompassing hierarchical structure of somatic, emotional, cognitive, behavioral, and social factors of importance in the perpetuation of FSS based on expert opinions. This structure will guide the development of personalized treatment of FSS.
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http://dx.doi.org/10.1016/j.genhosppsych.2016.10.008DOI Listing
December 2017

Incorporating measurement error in n = 1 psychological autoregressive modeling.

Front Psychol 2015 28;6:1038. Epub 2015 Jul 28.

Department of Methodology and Statistics, Utrecht University Utrecht, Netherlands.

Measurement error is omnipresent in psychological data. However, the vast majority of applications of autoregressive time series analyses in psychology do not take measurement error into account. Disregarding measurement error when it is present in the data results in a bias of the autoregressive parameters. We discuss two models that take measurement error into account: An autoregressive model with a white noise term (AR+WN), and an autoregressive moving average (ARMA) model. In a simulation study we compare the parameter recovery performance of these models, and compare this performance for both a Bayesian and frequentist approach. We find that overall, the AR+WN model performs better. Furthermore, we find that for realistic (i.e., small) sample sizes, psychological research would benefit from a Bayesian approach in fitting these models. Finally, we illustrate the effect of disregarding measurement error in an AR(1) model by means of an empirical application on mood data in women. We find that, depending on the person, approximately 30-50% of the total variance was due to measurement error, and that disregarding this measurement error results in a substantial underestimation of the autoregressive parameters.
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http://dx.doi.org/10.3389/fpsyg.2015.01038DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4516825PMC
August 2015

The day-to-day concurrence of bodily complaints and affect in patients with severe somatoform disorder.

Scand J Psychol 2015 Oct 1;56(5):553-9. Epub 2015 Jun 1.

Altrecht Psychosomatic Medicine Eikenboom, Zeist, the Netherlands.

Based on the concept of somatization, psychological distress can be experienced as symptoms of physical illness. This suggests a close-fitting intra-individual association between bodily complaints and mood in patients with somatoform disorder (SFD). The contemporaneous day-to-day complaints-mood association was investigated in patients with severe chronic SFD using an ecological momentary assessment (EMA) design. Eleven patients, who had recently received specialized tertiary care treatment for severe chronic SFD, kept an online electronic diary for four consecutive weeks. They were prompted at intervals throughout the day to complete questions on their momentary primary symptoms (pain and fatigue), and mood state (negative and positive). For each measure, day-mean aggregated values were computed and analyzed using linear multilevel (mixed model) regression analysis. Fixed factor results showed that symptoms were associated with both negative mood state (β = 0.47) and positive mood state (β = -0.59). Random results, however, indicated large inter-individual differences, with correlations varying between 0.17 and 0.99 for negative affect, and between -0.88 and 0.14 for positive affect. A substantial day-to-day contemporaneous association between symptoms and affect across subjects, as well as large inter-individual differences in this association, were demonstrated in patients with severe chronic SFD. EMA-data showing the relationship between both negative and (inverse) positive mood and complaints has potential clinical relevance: providing SFD patients with feedback consisting of their personal day-to-day concurrency graph may promote their understanding of their own complaints in a broader context than the somatic area.
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http://dx.doi.org/10.1111/sjop.12228DOI Listing
October 2015

Intensive multidisciplinary treatment of severe somatoform disorder: a prospective evaluation.

J Nerv Ment Dis 2015 Feb;203(2):141-8

*Altrecht Psychosomatic Medicine Eikenboom, Zeist; †University of Groningen, University Medical Center Groningen, Interdisciplinary Center Psychopathology and Emotion Regulation, Groningen; and ‡Department of Clinical and Health Psychology, Utrecht University, Utrecht, the Netherlands.

Chronic severe somatoform disorder (SFD) is resistant to treatment. In a prospective observational study, we evaluated an intensive multidisciplinary treatment focusing on body-related mentalization and acceptance. Patients included in the study were 183 (146 women, 37 men) of 311 eligible patients with chronic severe SFD, referred consecutively to a specialized tertiary care center between 2002 and 2009. Primary outcome measures were somatic symptoms (SCL-90) and health-related quality of life (EuroQol 5-Dimensional [EQ-5D]). These measures were assessed four times before treatment (on intake, twice during an observation period, at start of treatment) and four times after treatment (during follow-up for 2 years). Multilevel analysis was used to separate effects of time (maturation) and treatment. Results revealed significant improvements in SCL-90 somatic symptoms (d = 0.51), EQ-5D index (d = 0.27), and EQ visual analogue scale (d = 0.56). Significant reductions were also observed in SCL-90 anxiety, depression, and overall psychopathology as well as in medical consumption associated with psychiatric illness (Trimbos/iMTA Questionnaire for Costs Associated With Psychiatric Illness). Large interindividual differences were found in treatment outcome. The long-term improvement seen in many patients suggests that intensive multidisciplinary tertiary care treatment is a useful approach to chronic severe SFD.
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http://dx.doi.org/10.1097/NMD.0000000000000250DOI Listing
February 2015

Authors' reply.

Br J Psychiatry 2014 Mar;204(3):244

Jurrijn A. Koelen, University of Leuven, Tiensestraat 102, 3000 Leuven, Belgium. Email: Allan Abbass, Departments of Psychiatry and Psychology, Dalhousie University, Halifax, Canada; Jan H. Houtveen, Rinie Geenen, Department of Clinical and Health Psychology, Utrecht University, Utrecht, The Netherlands.

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http://dx.doi.org/10.1192/bjp.204.3.244DOI Listing
March 2014

Effectiveness of psychotherapy for severe somatoform disorder: meta-analysis.

Br J Psychiatry 2014 Jan;204(1):12-9

Jurrijn A. Koelen, MSc, Altrecht Psychosomatic Medicine, Zeist, The Netherlands, and Department of Psychology, University of Leuven, Leuven, Belgium; Jan H. Houtveen, PhD, Department of Clinical and Health Psychology, Utrecht University, Utrecht, The Netherlands; Allan Abbass, MD, PhD, Departments of Psychiatry and Psychology, Dalhousie University, Halifax, Canada; Patrick Luyten, PhD, Faculty of Psychology and Educational Sciences, University of Leuven, Leuven, Belgium, and Research Department of Clinical, Educational and Health Psychology, University College London, UK; Elisabeth H. M. Eurelings-Bontekoe, PhD, Department of Clinical and Health Psychology, Leiden University, Leiden; Saskia A. M. Van Broeckhuysen-Kloth, PhD, Martina E. F. Bühring, MD, PhD, Altrecht Psychosomatic Medicine, Zeist; Rinie Geenen, PhD, Department of Clinical and Health Psychology, Utrecht University, Utrecht, The Netherlands.

Background: Patients with severe somatoform disorder (in secondary and tertiary care) typically experience functional impairment associated with physical symptoms and mental distress. Although psychotherapy is the preferred treatment, its effectiveness remains to be demonstrated.

Aims: To examine the effectiveness of psychotherapy for severe somatoform disorder in secondary and tertiary care compared with treatment as usual (TAU) but not waiting-list conditions.

Method: Main inclusion criteria were presence of a somatoform disorder according to established diagnostic criteria and receiving psychotherapy for somatoform disorder in secondary and tertiary care. Both randomised and non-randomised trials were included. The evaluated outcome domains were physical symptoms, psychological symptoms (depression, anxiety, anger, general symptoms) and functional impairment (health, life satisfaction, interpersonal problems, maladaptive cognitions and behaviour).

Results: Ten randomised and six non-randomised trials were included, comprising 890 patients receiving psychotherapy and 548 patients receiving TAU. Psychotherapy was more effective than TAU for physical symptoms (d = 0.80 v. d = 0.31, P<0.05) and functional impairment (d = 0.45 v. d = 0.15, P<0.01), but not for psychological symptoms (d = 0.75 v. d = 0.51, P = 0.21). These effects were maintained at follow-up.

Conclusions: Overall findings suggest that psychotherapy is effective in severe somatoform disorder. Future randomised controlled studies should examine specific interventions and mechanisms of change.
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http://dx.doi.org/10.1192/bjp.bp.112.121830DOI Listing
January 2014

Design of an ecological momentary assessment study of exposure to radiofrequency electromagnetic fields and non-specific physical symptoms.

BMJ Open 2013 Aug 29;3(8):e002933. Epub 2013 Aug 29.

National Institute for Public Health and the Environment, Bilthoven, The Netherlands.

Introduction: Idiopathic Environmental Intolerance (IEI) attributed to electromagnetic fields (EMF) refers to self-reported sensitivity mainly characterised by the attribution of non-specific physical symptoms to low-level EMF exposure emitted from sources such as mobile phones. Scientific studies have not provided evidence for the existence of IEI-EMF, but these studies did not resemble the real-life situation or suffered from poor exposure characterisation and biased recall of health symptoms. To improve existing methods for the study of IEI-EMF, an Ecological Momentary Assessment (EMA) study is designed.

Methods And Analysis: The study is an EMA study in which respondents carry personal exposure metres (exposimeters) that measure radiofrequency (RF) EMF, with frequent assessment of health symptoms and perceived EMF exposure through electronic diary registration during five consecutive days. Participants will be a selection from an epidemiological study who report to be sensitive to RF EMF. The exposimeters measure electric field strength in 12 frequency bands. Diary questions include the occurrence and severity of 10 non-specific physical symptoms, mood states and perceived exposure to (sources of) EMF. The relationship of actual and perceived EMF exposure and mood with non-specific physical symptoms will be analysed using multilevel regression analysis with time-shift models.

Discussion: The study has several advantages over previous studies, including assessment of personal EMF exposure and non-specific physical symptoms by an ecological method with a minimised chance of recall bias. The within-person design reduces confounding by time-stable factors (eg, personal characteristics). In the conduct of the study and the analysis and interpretation of its outcomes, some methodological issues including a high participant burden, reactivity, compliance to the study protocol and the potential of chance findings due to multiple statistical testing will be accounted for and limited as much as possible.
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http://dx.doi.org/10.1136/bmjopen-2013-002933DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3758982PMC
August 2013

Prodromal functioning of migraine patients relative to their interictal state--an ecological momentary assessment study.

PLoS One 2013 16;8(8):e72827. Epub 2013 Aug 16.

Department of Clinical and Health Psychology, Faculty of Social and Behavioral Sciences, Utrecht University, The Netherlands.

Smartphones were used in an online Ecological Momentary Assessment (EMA) design to test prodromal functioning relative to the interictal state in migraine patients. Eighty-seven participants completed an electronic diary 4 times daily during 3-6 weeks to monitor their migraine attacks. Twice daily the diary additionally included 16 multi-answer questions covering physical symptoms (30 items), cognitive-affective functioning (25 items) and external factors (25 items). Eight clustered prodromal features were identified in the current study: sensory sensitivity, pain/stiffness, fatigue, cognitive functioning, positive affect, negative affect, effort spent and stressors encountered. Per feature, individual change scores with interictal control days--excluding 24-hour post-attack recovery--were computed for six 12-hour pre-attack time windows covering three prodromal days. Linear mixed model (fixed-effect) analysis established significant increases in sensory sensitivity, pain/stiffness and fatigue, and a tendency for increased negative affect, in the 12 hours prior to the attack. Positive affect and cognitive functioning were impaired both in the 25-36 hour and--more strongly--in the 12-hour time window before the attack. No effects were found for effort spent and stressors encountered. Exploratory (random effect) analysis revealed significant individual differences in the change scores in sensory sensitivity, pain/stiffness, fatigue and negative affect. It is concluded that the prodromal change in migraine--relative to interictal functioning--predominantly exists within the last 12 hours before attack onset. Individual diversity is large, however. Future research should zoom in to identify prodrome development within the 12 pre-attack hours as well as to isolate individual patterns.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0072827PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3745475PMC
January 2015

Infection load as a predisposing factor for somatoform disorders: evidence from a Dutch General Practice Registry.

Psychosom Med 2013 Oct 19;75(8):759-64. Epub 2013 Aug 19.

Clinical and Health Psychology, Research Institute of Social and Behavioral Sciences, Utrecht University, T.E. Lacourt, Heidelberglaan 1, 3584 CS, Utrecht, the Netherlands.

Objective: Somatoform disorders (SDs) are characterized by chronic multiple functional somatic (FS) symptoms. It has been suggested that infections may be triggers for FS symptoms to occur, pointing to the immune system as a pathogenic factor in their development. The current study aimed to compare the prevalence of infections (i.e., infection load) in the history of patients with SDs with that of matched controls.

Methods: Samples (n = 185) were identified in the Psychiatric Case Register Middle Netherlands and the Julius General Practitioners Network. Patients with an SD diagnosis in the Psychiatric Case Register Middle Netherlands were compared with matched persons without somatoform complaints (controls) on their infection load in two periods before the date of the psychiatric diagnosis or a matched date for the controls (i.e., the total period for which data were available and a 3-year period). Infection load was defined as the total number of infections documented in the Julius General Practitioners Network.

Results: Patients with SD had significantly more infections than did controls in both periods (total period: mean [standard error] = 0.87 [0.10] versus 0.51 [0.06], z = -3.08, p = .002; 3-year period: 3.44 [0.47] versus 2.15 [0.50], z = -2.91, p = .004).

Conclusions: Results show that patients with SD have a higher infection load preceding their diagnosis as compared with matched controls, implicating that infection load may indeed predispose for developing FS symptoms. These findings emphasize the importance of further research on immunological mechanisms in FS symptoms. Limitations of the study are discussed.
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http://dx.doi.org/10.1097/PSY.0b013e3182a3d91fDOI Listing
October 2013

The impact of emotion-related autonomic nervous system responsiveness on pain sensitivity in female patients with fibromyalgia.

Psychosom Med 2013 Oct 6;75(8):765-73. Epub 2013 Aug 6.

Department of Medical Psychology, Radboud University Nijmegen Medical Center, PO Box 9101, 6500 HB Nijmegen, The Netherlands.

Objective: Patients with fibromyalgia have shown hyporeactive autonomic nervous system (ANS) responses to physical stressors, augmented pain to ANS changes, and heightened negative emotions, which can increase pain. This study examined ANS reactivity to negative emotions and its association with pain in fibromyalgia and control participants.

Methods: Sixty-two women with fibromyalgia and 59 women in a control group recalled neutral, and anger- and sadness-eliciting experiences while ANS activity was monitored. Clinical and experimental pain were assessed in response to each emotion.

Results: Compared with neutral recall, heart rate (p = .050), mean arterial pressure (p < .001), and high-frequency heart rate variability (p = .012) increased in response to sadness, whereas heart rate decreased (p = .002) and mean arterial pressure increased (p < .001) in response to anger; however, ANS responses did not differ between patients and control participants (all p > .29). Among patients only, decreased preejection period (anger-pain threshold: r = 0.31, p = .018) and total peripheral resistance in response to negative emotions (anger-pain tolerance: r = 0.35, p = .025; sadness-pain threshold: r = 0.51, p < .001; sadness-pain tolerance: r = 0.61, p < .001) correlated with more pain.

Conclusions: These data suggest that the ANS is not hyporesponsive to elicited emotions in fibromyalgia; however, patients with a larger pain response showed an ANS response pattern reflecting heightened β-adrenergic and reduced α-adrenergic reactivity. Future research should test whether a specific ANS response pattern to emotions is a consequence of increased pain or whether it amplifies pain.
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http://dx.doi.org/10.1097/PSY.0b013e3182a03973DOI Listing
October 2013

[Not Available].

Authors:
Jan Houtveen

Tijdschr Psychiatr 2013 ;55(3):224-6

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May 2013

"Functional somatic syndromes, one or many?" An answer by cluster analysis.

J Psychosom Res 2013 Jan 6;74(1):6-11. Epub 2012 Oct 6.

Clinical and Health Psychology, Utrecht University, The Netherlands.

Objective: The aim of the present study was to address the lumper-splitter discussion on functional somatic syndromes by applying k-means cluster analyses on a heterogeneous sample of persons with unexplained somatic complaints. In favor of the lumper-side of the debate, clusters should differ only on the overall severity of the somatic complaints that were assessed. According to the splitters view, clusters should differ in symptom-specific patterns.

Methods: Three-hundred ninety four subjects with functional somatic symptoms were clustered based on their scores on 47 somatic symptoms. Three cluster solutions (k=2,3, and 4 clusters) were compared on overall symptom severity, symptom patterns, and psychological distress.

Results: Results showed that in all three solutions the clusters were defined by increasing total symptom scores and increasing psychological distress. Cluster-specific symptom patterns where evident only when more clusters (three or four) were allowed. The best fit index was found for a 2-cluster solution.

Conclusion: The finding of symptom specific patterns in clusters which could not be differentiated on overall symptom severity is in favor of the splitters' view. The finding that all other clusters could be discriminated on overall symptom severity and that the 2-cluster solution had the best fit is in favor of the lumpers' view.
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http://dx.doi.org/10.1016/j.jpsychores.2012.09.013DOI Listing
January 2013

EMDR and mindfulness. Eye movements and attentional breathing tax working memory and reduce vividness and emotionality of aversive ideation.

J Behav Ther Exp Psychiatry 2011 Dec 12;42(4):423-31. Epub 2011 Apr 12.

Clinical and Health Psychology, Utrecht University, PO Box 80140, 3508 TC Utrecht, The Netherlands.

Background And Objectives: Eye Movement Desensitization and Reprocessing (EMDR) and Mindfulness-Based Cognitive Therapy (MBCT) are effective in reducing the subjective impact of negative ideation. In both treatments, patients are encouraged to engage in a dual-task (eye movements (EM) in the case of EMDR and attentional breathing (AB) in the case of MBCT) while they experience negative thoughts or images. Working memory theory explains the effects of EM by suggesting that it taxes limited working memory resources, thus rendering the image less vivid and emotional. It was hypothesized that both AB and EM tax working memory and that both reduce vividness and emotionality of negative memories.

Methods: Working memory taxation by EM and AB was assessed in healthy volunteers by slowing down of reaction times. In a later session, participants retrieved negative memories during recall only, recall + EM and recall + AB (study 1). Under improved conditions the study was replicated (study 2).

Results: In both studies and to the same degree, attentional breathing and eye movements taxed working memory. Both interventions reduced emotionality of memory in study 1 but not in study 2 and reduced vividness in study 2 but not in study 1.

Limitations: EMDR is more than EM and MBCT is more than AB. Memory effects were assessed by self reports.

Conclusions: EMDR and MBCT may (partly) derive their beneficial effects from taxing working memory during recall of negative ideation.
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http://dx.doi.org/10.1016/j.jbtep.2011.03.004DOI Listing
December 2011

Using multilevel path analysis in analyzing 24-h ambulatory physiological recordings applied to medically unexplained symptoms.

Psychophysiology 2010 May 22;47(3):570-8. Epub 2009 Dec 22.

Department of Clinical and Health Psychology, Faculty of Social Sciences, Utrecht University, 3508 TC Utrecht, The Netherlands.

A non-clinical group high on heterogeneous medically unexplained symptoms (MUS; n=97) was compared with healthy controls (n=66) on the within-subject relationships between physiological measures using multilevel path analysis. Momentary experienced somatic complaints, mood (tension and depression), cardiac autonomic activity (inter-beat intervals, pre-ejection period (PEP), and respiratory sinus arrhythmia (RSA)) and respiration (rate and partial pressure of CO(2) at the end of a normal expiration) were monitored for 24 h using electronic diary and ambulatory devices. Relationships between measures were controlled for diurnal variation and individual means. Only subtle group differences were found in the diurnal rhythm and in the within-subject relationships between physiological measures. For participants high on MUS, within-subject changes in bodily symptoms were related to changes in mood, but only marginally to the physiological measures. Results of the current path analysis confirm the subordinate role of cardiac autonomic and respiratory parameters in MUS.
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http://dx.doi.org/10.1111/j.1469-8986.2009.00951.xDOI Listing
May 2010

Comparing low frequency heart rate variability and preejection period: two sides of a different coin.

Psychophysiology 2008 Nov 24;45(6):1086-90. Epub 2008 Sep 24.

Department of Biological Psychology, VU University Amsterdam, Amsterdam, The Netherlands.

It has been hypothesized that the ratio of heart rate variability in the low- (LF) and high- (HF) frequency bands may capture variation in cardiac sympathetic control. Here we tested the temporal stability of the LF/HF ratio in 24-h ambulatory recordings and compared this ratio to the preejection period (PEP), an established measure of cardiac sympathetic control. Good temporal stability was found across a period of 3.3 years (.46
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http://dx.doi.org/10.1111/j.1469-8986.2008.00710.xDOI Listing
November 2008

Negative affect and 24-hour ambulatory physiological recordings as predictors of spontaneous improvement of medically unexplained symptoms.

Scand J Psychol 2008 Dec 2;49(6):591-601. Epub 2008 Sep 2.

Department of Clinical and Health Psychology, Utrecht University, Utrecht, The Netherlands.

The predictive value for spontaneous improvement in individuals suffering from medically unexplained symptoms (MUS) was explored of (1) anxiety and depression obtained from questionnaires, (2) negative affective states obtained from experience-sampling, and (3) ambulatory-assessed real-life physiological recordings. Sixty-seven individuals with MUS and 61 healthy controls were included. Twenty-four hour ambulatory recordings of cardiac autonomic activity, respiration, end-tidal CO(2) and saliva cortisol were combined with experience-sampling of somatic complaints and mood. Complaints were assessed again after one year. Although a reduction in symptoms (25%) was found, this could not be predicted from initial anxiety and depression. Improvement was somewhat related to relatively low diary reports of fatigue, especially in the late-afternoon and evening (3% variance explained). From the physiological measures only relatively high PetCO(2) values in the morning predicted improvement (5% explained). It was concluded that spontaneous recovery from MUS is hard to predict from self-reported distress and ambulatory physiological recordings.
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http://dx.doi.org/10.1111/j.1467-9450.2008.00684.xDOI Listing
December 2008

Mobile Web-based monitoring and coaching: feasibility in chronic migraine.

J Med Internet Res 2007 Dec 31;9(5):e38. Epub 2007 Dec 31.

Department of Clinical and Health Psychology, Utrecht University, PO Box 80.140, 3508 TC Utrecht, The Netherlands.

Background: The Internet can facilitate diary monitoring (experience sampling, ecological momentary assessment) and behavioral coaching. Online digital assistance (ODA) is a generic tool for mobile Web-based use, intended as an adjuvant to face-to-face or Internet-based cognitive behavioral treatment based. A current ODA application was designed to support home-based training of behavioral attack prevention in chronic migraine, focusing on the identification of attack precursors and the support of preventive health behaviour.

Objective: The aim was to establish feasibility of the ODA approach in terms of technical problems and participant compliance, and ODA acceptability on the basis of ratings of user-friendliness, potential burden, and perceived support of the training for behavioral attack prevention in migraine.

Methods: ODA combines mobile electronic diary monitoring with direct human online coaching of health behavior according to the information from the diary. The diary contains three parts covering the following: (1) migraine headache and medication use, (2) attack precursors, and (3) self-relaxation and other preventive behavior; in addition, menstruation (assessed in the evening diary) and disturbed sleep (assessed in the morning diary) is monitored. The pilot study consisted of two runs conducted with a total of five women with chronic migraine without aura. ODA was tested for 8.5 days (range 4-12 days) per participant. The first test run with three participants tested 4-5 diary prompts per day. The second run with another three participants (including one subject who participated in both runs) tested a reduced prompting scheme (2-3 prompts per day) and minor adaptations to the diary. Online coaching was executed twice daily on workdays.

Results: ODA feasibility was established on the basis of acceptable data loss (1.2% due to the personal digital assistant; 5.6% due to failing Internet transmission) and good participant compliance (86.8% in the second run). Run 1 revealed some annoyance with the number of prompts per day. Overall ODA acceptability was evident by the positive participant responses concerning user-friendliness, absence of burden, and perceived support of migraine attack prevention. The software was adapted to further increase the flexibility of the application.

Conclusions: ODA is feasible and well accepted. Tolerability is a sensitive issue, and the balance between benefit and burden must be considered with care. ODA offers a generic tool to combine mobile coaching with diary monitoring,independently of time and space. ODA effects on improvement of migraine remain to be established.
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http://dx.doi.org/10.2196/jmir.9.5.e38DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2270417PMC
December 2007

Medically unexplained symptoms and between-group differences in 24-h ambulatory recording of stress physiology.

Biol Psychol 2007 Oct 30;76(3):239-49. Epub 2007 Aug 30.

Department of Clinical and Health Psychology, Utrecht University, Utrecht, The Netherlands. [email protected]/nl

People with medically unexplained symptoms (MUS) often have a comorbid history of stress and negative affect. Although the verbal-cognitive and (peripheral) physiological stress systems have shown a great degree of independence, at the same time it is claimed that chronic stress and negative affect can result in a disregulated physiological stress system, which may lead to MUS. Previous studies could not demonstrate a straightforward between subject relationship between MUS and stress physiology, supporting the view of independence. The aim of the current study was to further explore this relationship using an improved methodology based on ecologically valid 24-h real-life ambulatory recordings. Seventy-four participants (19 male; 55 female) with heterogeneous MUS were compared with 71 healthy controls (26 male; 45 females). Momentary experienced somatic complaints and mood, heart rate, cardiac autonomic activity, respiration and saliva cortisol were monitored using electronic diary and ambulatory registration devices. Participants with MUS reported much more momentary complaints and negative affect as compared to controls. Although MUS seemed to be associated with elevated heart rate and reduced low and very-low frequency heart period variability, these effects disappeared after controlling for differences in sports behaviour. No group differences were found for cardiac autonomic activity, respiration, end-tidal CO(2) and saliva cortisol. Our 24-h real-life ambulatory study did not support the existence of a connection between MUS and disregulated peripheral stress physiology. Future studies may instead focus on central measures to reveal potential abnormalities such as deviant central processing of visceral signals in MUS patients.
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http://dx.doi.org/10.1016/j.biopsycho.2007.08.005DOI Listing
October 2007

Heterogeneous medically unexplained symptoms and immune function.

Brain Behav Immun 2007 Nov 5;21(8):1075-82. Epub 2007 Jun 5.

Department of Clinical and Health Psychology, Utrecht University, Faculty of Social and Behavioural Sciences, P.O. Box 80.140, 3508 TC Utrecht, The Netherlands.

It has been suggested that dysregulation of immune-to-brain communication plays a role in the biopsychological process underlying medically unexplained symptoms (MUS). Immune and non-immune stressors can both be involved in the activation of the central sickness-behavioural-system leading to complaints like malaise, pain and fatigue. We hypothesized increased pro-inflammatory and/or reduced anti-inflammatory cytokine activity to exist in MUS patients. Twenty-seven participants (4 male; 23 female) with heterogeneous MUS were compared with 27 healthy controls (6 male; 21 females). Blood samples were analysed for leukocyte subset cell counts, in vitro T-cell mitogen-stimulated cytokine production (IL-2, IL-4, IL-5, IL-6, IL-10, TNF-alpha and IFN-gamma) and in vitro monocyte cytokine release (IL-1beta, IL-6, IL-8, IL-10 and TNF-alpha) in response to increasing concentrations of LPS. No significant group differences were found for any of the cytokines measured. One unexpected exception was an elevation in the number of circulating B and NK-cells in participants high on MUS. Nonetheless, no support was found for the hypothesized immunological dysregulation in peripheral blood leukocyte function of MUS patients.
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http://dx.doi.org/10.1016/j.bbi.2007.04.008DOI Listing
November 2007

Exhaustion and endocrine functioning in clinical burnout: an in-depth study using the experience sampling method.

Biol Psychol 2007 May 20;75(2):176-84. Epub 2007 Feb 20.

Utrecht University, Faculty of Social Sciences, Department of Clinical and Health Psychology, P.O. Box 80140, 3508 TC Utrecht, The Netherlands.

The current study investigates the relationship between HPA-axis functioning and burnout symptoms by employing an electronic symptom diary. This diary method circumvents the retrospection bias induced by symptom questionnaires and allows to study relationships within-in addition to between-subjects. Forty two clinically burned-out participants completed the exhaustion subscale of the Maslach burnout inventory and kept an electronic diary for 2 weeks to assess momentary exhaustion and daily recovery through sleep. On 3 consecutive weekdays within the diary period, saliva was sampled to determine the cortisol awakening response (CAR), levels of dehydroepiandrosterone-sulphate (DHEAS) on the first 2 weekdays, and to conduct the dexamethasone suppression test (DST) on the third weekday. We found significant relationships between endocrine values and general momentary symptom severity as assessed with the diary, but not with the retrospective questionnaire-assessed burnout symptoms. Simultaneous assessments of endocrine values and burnout symptoms assessed with the diary after awakening rendered significant associations between persons, and a trend within persons. More severe burnout symptoms were consistently associated with a lower level and smaller increase of CAR, higher DHEAS levels, smaller cortisol/DHEAS ratios and a stronger suppression after DST. Burnout symptoms were significantly related to endocrine functioning in clinical burnout under the best possible conditions of symptom measurement. This adds support to the view that severity of burnout symptoms is associated with HPA-axis functioning.
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http://dx.doi.org/10.1016/j.biopsycho.2007.02.001DOI Listing
May 2007

Comparison of time and frequency domain measures of RSA in ambulatory recordings.

Psychophysiology 2007 Mar;44(2):203-15

Department of Biological Psychology, Vrije Universiteit Amsterdam, The Netherlands.

The extent to which various measures of ambulatory respiratory sinus arrhythmia (RSA) capture the same information across conditions in different subjects remains unclear. In this study the root mean square of successive differences (RMSSD), peak valley RSA (pvRSA), and high frequency power (HF power) were assessed during ambulatory recording in 84 subjects, of which 64 were retested after about 3 years. We used covariance structure modeling to test the equality of the correlations among three RSA measures over two test days and three conditions (daytime sitting or walking and nighttime sleep) and in groups with low, medium, and high mean heart rate (HR), or low, medium, and high mean respiration rate (RR). Results showed that ambulatory RMSSD, pvRSA, and HF power are highly correlated and that their correlation is stable across time, ambulatory conditions, and a wide range of resting HR and RR values. RMSSD appears to be the most cost-efficient measure of RSA.
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http://dx.doi.org/10.1111/j.1469-8986.2006.00490.xDOI Listing
March 2007

Recall bias in reporting medically unexplained symptoms comes from semantic memory.

J Psychosom Res 2007 Mar;62(3):277-82

Clinical and Health Psychology, Utrecht University, Utrecht, The Netherlands.

Objective: When people report somatic complaints retrospectively, they depend on their memory. Therefore, retrospective reports can be influenced by general beliefs on sickness and health from semantic memory. We hypothesized that individuals with medically unexplained symptoms (MUS) would have recall biases stronger than those of people without complaints when reporting symptoms retrospectively, and that this effect would be a function of time between symptom experience and report.

Methods: To compare two time frames, 37 participants who were high and low on MUS reported momentary symptoms combined by daily recall and weekly recall using an electronic diary.

Results: Both groups reported more symptoms when recalling the entire week than what could be expected from average momentary reports. However, participants high on MUS also reported more symptoms when recalling a week than when recalling a day. For this group, recall bias was not associated with peak heuristic or symptoms variability.

Conclusion: Symptom reports in people high on MUS increases as time passes by, probably as a results of a shift in memory retrieval strategy from using episodic knowledge to using semantic beliefs.
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http://dx.doi.org/10.1016/j.jpsychores.2006.11.006DOI Listing
March 2007

Effects of variation in posture and respiration on RSA and pre-ejection period.

Psychophysiology 2005 Nov;42(6):713-9

Department of Health Psychology, Utrecht University, Utrecht, The Netherlands.

The extent to which variation in posture and respiration can confound pre-ejection period and respiratory sinus arrhythmia (RSA) as indices of cardiac sympatho-vagal activity was examined. Within-subjects changes in these measures were assessed in 36 subjects during different postures and (paced) respiratory frequencies. Changes from supine to sitting to standing led to reduced RSA values and longer pre-ejection periods, reflecting the known decrease in vagal but not the increase of sympathetic activity. Multilevel path analysis showed that within-subjects changes in sympatho-vagal balance were faithfully reflected by changes in interbeat interval, but imperfectly by changes in RSA and pre-ejection period. It was concluded that pre-ejection period should be stratified for posture and RSA for respiratory frequency to reliably index changes in sympatho-vagal balance when these factors are prone to change (e.g., during 24-h ambulatory recording).
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http://dx.doi.org/10.1111/j.1469-8986.2005.00363.xDOI Listing
November 2005

Validation of the thoracic impedance derived respiratory signal using multilevel analysis.

Int J Psychophysiol 2006 Feb;59(2):97-106

Department of Health Psychology, Utrecht University, P.O. Box 80140, 3508 TC Utrecht, The Netherlands.

The purpose of the current study was to validate the change in thoracic impedance (dZ) derived respiratory signal obtained from four spot electrodes against incidental spirometry. Additionally, a similar validation was performed for a dual respiratory belts signal to compare the relative merit of both methods. Participants were 38 healthy adult subjects (half male, half female). Cross-method comparisons were performed at three (paced) respiration frequencies in sitting, supine and standing postures. Multilevel regression was used to examine the within- and between-subjects structure of the relationship between spirometric volume and the respiratory amplitude signals obtained from either dZ or respiratory belts. Both dZ derived respiratory rate and dual belts derived respiratory rate accurately reflected the pacing frequencies. For both methods, fixed factors indicated acceptable but posture-specific regression on spirometric volume. However, random factors indicated large individual differences, which was supported by variability of gain analyses. It was concluded that both the dZ and dual belts methods can be used for measurement of respiratory rate and within-subjects, posture-specific, changes in respiratory volume. The need for frequent subject-specific and posture-specific calibration combined with relatively large measurement errors may strongly limit the usefulness of both methods to assess absolute tidal volume and minute ventilation in ambulatory designs.
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http://dx.doi.org/10.1016/j.ijpsycho.2005.02.003DOI Listing
February 2006

Circadian variation in base rate measures of cardiac autonomic activity.

Eur J Appl Physiol 2004 Oct 8;93(1-2):39-46. Epub 2004 Jul 8.

Department of Psychology, University of Amsterdam, Roetersstraat 15, 1018 WB, Amsterdam, The Netherlands.

To investigate the role of the circadian pacemaker in autonomic modulation of base rate cardiac activity, 29 healthy subjects participated in a constant routine protocol. They were randomly divided into two groups in order to manipulate prior wakefulness. Group 1 started at 0900 hours immediately after a monitored sleep period, while group 2 started 12 h later. Measures of interbeat intervals (IBIs), respiratory sinus arrhythmia (RSA, an estimate of parasympathetic activity), pre-ejection period (PEP, an estimate of sympathetic activity), and core body temperature (CBT) were recorded continuously. Multilevel regression analyses (across-subjects) revealed significant 24- and/or 12-h sinusoidal circadian variation for CBT, IBI, and RSA, but not for PEP. Subject-specific 24+12 h sinusoidal fits demonstrated a convergence of phase distribution for IBI and RSA of group 1 similar to CBT, while PEP showed a relatively large (i.e. random) distribution of phase. In group 2, all cardiac measures showed large distributions of phase. Unexpected results in the cardiac measures were found in group 2, probably caused by group differences in prior activation. Also, effects of sleep deprivation were observed for IBI and RSA in group 2. Consequently, all cardiac measures revealed significant sinusoidal x group interactions, a result not shown in CBT. These findings were interpreted as an indication for circadian endogenous parasympathetic modulation of cardiac activity that is mainly confounded by prior wakefulness that extends 24 h, while the sympathetic modulation is relatively uncoupled from the endogenous circadian drive and mainly influenced by prior activation.
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http://dx.doi.org/10.1007/s00421-004-1158-6DOI Listing
October 2004

Circadian variation in cardiac autonomic activity: reactivity measurements to different types of stressors.

Chronobiol Int 2004 Jan;21(1):107-29

Department of Psychology, University of Amsterdam, The Netherlands.

The role of endogenous circadian rhythmicity in autonomic cardiac reactivity to different stressors was investigated. A constant routine protocol was used with repeated exposure to a dual task and a cold pressor test. The 29 subjects were randomly divided into two groups in order to manipulate prior wakefulness. Group 1 started at 09:00 h immediately after a monitored sleep period, whereas group 2 started 12 h later. Measures of interbeat intervals (IBI), respiratory sinus arrythmia (RSA, a measure of parasympathetic activity), pre-ejection period (PEP, a measure of sympathetic activity), as well as core body temperature (CBT) were recorded continuously. Multilevel regression analyses (across-subjects) revealed significant (mainly 24 h) sinusoidal circadian variation in the response to both stressors for IBI and RSA, but not for PEP. Individual 24 + 12 h cosine fits demonstrated a relatively large interindividual variation of the phases of the IBI and RSA rhythms, as compared to that of the CBT rhythm. Sinusoidal by group interactions were found for IBI and PEP, but not for RSA. These findings were interpreted as an indication for endogenous circadian and exogenous parasympathetic (vagal) modulation of cardiac reactivity, while sympathetic reactivity is relatively unaffected by the endogenous circadian drive and mainly influenced by exogenous factors.
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http://dx.doi.org/10.1081/cbi-120027983DOI Listing
January 2004
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