A test of delayed recovery following stressful stimulation in four psychosomatic disorders

Cognitive, behavioral and physiological reactivity to pain as a predictor of long-term pain in rheumatoid arthritis patients

A heightened reactivity to pain is assumed to play a significant role in the maintenance and exacerbation of pain in patients with chronic pain. In a prospective study involving 95 rheumatoid arthritis (RA) patients, the relative contribution of self-reported cognitive, behavioral and physiological components of pain reactivity were examined for a change in pain within 1 year. Regression analyses indicated that self-reported physiological reactivity predicted an increase in clinical and self-reported pain after 1 year, but not cognitive and behavioral reactivity. Neither disease activity nor neuroticism mediated or moderated the relationship of pain reactivity to long-term pain. However, structural equation modeling revealed that neuroticism directly affected physiological reactivity to pain, which in turn was the only significant predictor for subsequent pain. The results of this study underline the crucial role of physiological pain reactivity for exacerbation of pain in RA patients and are indicative for a symptom-specific pattern of physiological pain reactivity that is sustained by psychological predisposition and respondent learning processes.

A proposed psychosomatic etiologic model for rheumatoid arthritis

This model attributes rheumatoid arthritis to reduction or loss of muscle tone. It is hypothesized that tone is maintained via a neurological feedback loop consisting of a spontaneous (fusimotor) signal from the central nervous system (CNS), a return signal from the sensors and a toning signal from the CNS to the muscles. Frequency of return and toning signals are thought to be identical. Arthritis patients believed to react to psychological stress with increased fusimotor frequency (i.e. muscle tension) which over-stretches the sensing tissue. Because of this damage, the lower fusimotor frequency following the stress episode cannot elicit an adequate frequency response from the sensors and this leads to a matching decline in toning pulse frequency and hence muscle tone. Reduced vascular/cardiac tone lowers blood pressure triggering a compensatory hypervolemia. The resulting hypoxia increases vascular leakage causing tissue/lymph edema and pleural/pericardial/joint effusions. Regular ingestion of ephedrine is thought to increase fusimotor frequency and this reactivates the sensors re-establishing muscle tone.

Psychophysiological reactivity in pediatric migraine patients and healthy controls

The hypothesis that physiological responses of migraine patients are symptom-specific was evaluated in 29 children (age range 8-16 years) suffering from migraine and 10 healthy control children. The assessment included two major stress phases and a relaxation period. A standard laboratory stressor (a subtraction task) and parent-child conflict served as stressors. A total of six physiological parameters were measured: pulse amplitude at two extracranial (A. temporalis, A. supraorbitalis) and one peripheral (index finger) sites; finger temperature; heart rate; and skin-conductance level. There were no significant group differences in autonomic arousal. Moreover, extracranial and peripheral vasomotor activity was not different between groups, a finding which might be partially due to the considerable interindividual variability. The implications of the results are discussed taking into account that studying pediatric rather than adult migraine patients allows to minimize the potentially confounding impact of factors such as headache chronicity, medication, and additional nonmigraine headaches.

Pain measurement in arthritis

Objective. This paper reviews the major pain measurement methods used with adult patients with rheumatoid arthritis, osteoarthritis, and fibromyalgia. Methods and Results. The most frequently used measures are numerical and verbal rating (category) scales of pain intensity and affect. However, visual analogue scales and composite measures are preferable to category scales because they may be subjected to parametric statistical analyses and may be associated with greater sensitivity to treatment-related changes over time. Measurement of overt motor behaviors and pain threshold levels provides important information that cannot be assessed with rating scales. It also allows one to determine whether there are discrepancies between patients' ratings of their pain experiences and their behaviors. Measurement of psychophysiologic parameters are used to understand better how markers of immune system activity may mediate the relationships between psychological and environmental factors and patients' pain experiences. Conclusions. It is necessary to use multiple pain measurement methods for clinical and research purposes. These should include at least two measures of pain intensity and affect as well as a measure of pain behavior.

Psychophysiological theories on sympathetic nervous system reactivity in the development of essential hypertension

Psychophysiological theories on the development of essential hypertension are reviewed and evaluated. Two interconnected theories that relate behavior to essential hypertension and account for individual differences in susceptibility to disease are the "hyperreactivity" theory and "the symptom specificity" theory. The "hyperreactivity" theory identifies individual differences in autonomic nervous system reactivity as the pathophysiological mechanism and the "symptom specificity" theory suggests that inflexible, stereotypical responding increases the risk to develop hypertension. Based on a literature review, these theories are examined. There exist both case/control and prospective studies on autonomic nervous system reactivity and the development of hypertension. It is concluded that a neurogenically mediated hyperreactivity to stress is a precursor and not an effect of hypertension. Tasks that call for active but not passive coping efforts are more efficient elicitors of reactivity differences between those at high and low risk to develop hypertension in case/control studies. In prospective studies, active tasks may also have a predictive advantage over passive with respect to blood pressure development. In the early phase of hypertension, an increased cardiovascular reactivity is accompanied by increased neuroendocrine activation. In the later phase, heightened reactivity is confined to the cardiovascular system. This does not prove but is consistent with the notion that transient episodes of increased cardiac output translate into essential hypertension by causing vascular hypertrophy. Case/control studies suggest that an increased "symptom specificity", with stereotypical responding across multiple stressors, is independent of cardiovascular reactivity and a precursor of hypertension. The literature lacks prospective studies on the clinical relevance of stereotypical responding. It is suggested that the presence of both hyperreactivity and symptom specificity in a single individual increases the risk to develop essential hypertension.

Analysis of the physiological stress profile: the interrupted time-series design

Most research employing physiological stress profiling procedures has relied upon statistical analyses that are flawed in two ways: These analyses typically average the physiological levels observed across a series of observations during any one phase of the profile, thereby ignoring rate of change as a relevant parameter, and the problem of autocorrelation, or the natural correlation of time-series observations of the same physiologic activity, is unaddressed. We hope to introduce the biofeedback field to the technique of interrupted time-series analysis, which effectively deals with these two flaws. Interrupted time-series analysis additionally permits statistical conclusions based upon the stress profile of a single individual, thereby providing an objective basis for decisions concerning the effectiveness of training or the timing of changes in training for a single client. We describe the application of the technique to the analysis of a stress profile of a subject diagnosed as hypertensive.

Subjective stress sensitivity and physiological responses to an aversive auditory stimulus in migraine and control subjects

Subjective stress sensitivity and physiological parameters were compared between 24 migraine subjects and 24 matched headache-free controls during a multifrequency 85-dB (A) aversive auditory stressor and during a recovery period. Measures consisted of frontalis EMG, temporal artery blood volume pulse, heart rate, a stress sensitivity questionnaire, stress reaction during the stress-expectation period, and ratings of noise aversiveness. Migraine subjects showed a higher level of general stress sensitivity, increased situational stress sensitivity, and higher ratings of noise aversiveness; this supports the general notion that migraine sufferers are psychologically more sensitive toward stress stimulation than nonheadache controls. Physiologically, the migraine subjects differed from the control group only with regard to the temporal blood volume pulse during stress stimulation; this finding is consistent with Wolff's weak-link theory.

Psychophysiological comparisons of three kinds of headache subjects during and between headache states: analysis of post-stress adaptation periods

Twenty-eight chronic headache sufferers of three headache types (migraine, tension and combined migraine-tension) selected on the basis of explicit inclusion and exclusion criteria and matched on five demographic characteristics were assessed in a headache and non-headache state on a number of psychophysiological measures (frontalis, forearm and neck EMG; cephalic vasomotor response; hand surface temperature; heart rate and skin resistance level) and a number of stimulus conditions (baseline, self-control, cognitive and physical stressors). Results indicated no significant differences between the three headache groups or headache states on any measure during baseline condition. Analyses of post-stress adaptation periods led to the area of most significant differences, with a number of findings lending support for Sternbach's inadequate homeostatic responding hypothesis of migraine, but not tension, headache. No support was found for the sustained levels of muscle tension hypothesis of the etiology of tension headache. Implications for the etiology and treatment of headache are discussed.

Stress and rheumatoid arthritis: a survey of empirical evidence in human and animal studies

Literature concerning rheumatoid arthritis (RA) was reviewed with regard to the empirical evidence for the widely held view that the onset and course of the disease are influenced by stress variables. Human studies yielded contradictory results; there are at least two large well-controlled investigations that were not able to find a preponderance of life stress variables prior to the onset of the disease in RA patients compared to other patients or healthy subjects. Findings of animal studies are inconsistent, too: Some kinds of stress seem to abrogate, whereas others may rather enhance the development of rheumatic symptoms. Possible pathogenetic models are discussed to explain the influence of stress on the disease. For further research, the use of more sophisticated methods to assess life events, and prospective longitudinal studies in RA patients are suggested to find out whether stressful events antedate relapses. Such correlations should be examined for patients with seronegative and seropositive RA separately.