Self-reported stressors, symptom complaints and psychobiological functioning I: Cardiovascular stress reactivity.

Taking into account neuroticism and lifestyle variables (smoking and alcohol consumption), cardiovascular and psychological reactions to stressful films were studied in four groups of subjects selected on self-reported levels of recent stressor load and symptom complaints (low-load/low-symptoms: low-load/high-symptoms; high-load/low-symptoms; high-load/high-symptoms). The films were known either to stimulate or to depress cardiovascular activity. The results showed that psychological reactions (distress; deactivation; openness/involvement) were associated with group membership and condition. In addition, high-symptom subjects were characterized by faster resting heart rates and smaller ECG T-wave amplitudes (TWAs), reflective of greater sympathetic tone on the myocard. Further, low-symptom subjects, in particular those labeled as stress-resistant (high-load/low-symptoms), exhibited larger myocardial responses to the cardiovascular-stimulating films than did high-symptom subjects. Low-symptom subjects showed predicted variations in physiological responses to the different films, whereas the responses by the high-symptom subjects showed lesser variation across films. It is concluded that the cardiovascular responses of low-symptom subjects more accurately followed the energetic demands of the body, whereas the high-symptom subjects were in a comparatively enduring state of arousal.

Self-reported stressors, symptom complaints and psychobiological functioning-II: Psychoneuroendocrine variables.

The present study examined resting endocrinological functioning and endocrine responsivity to new challenges as a function of self-reported stress load and symptomatology. Following a baseline period, four groups of male subjects (low-load/low-symptoms; low-load/high-symptoms; high-load/low-symptoms; high-load/high-symptoms) were exposed to stressful films, followed by a rest period. Blood samples were drawn after each film and after the rest condition, and urinary samples were collected during two nights preceding the experimental session. Neuroendocrine variables measured in plasma included adrenaline, noradrenaline, ACTH, cortisol, growth hormone, prolactin, and testosterone. The urinary samples were assayed for noradrenaline and adrenaline (in relation to creatinin). High-symptom subjects had significantly higher plasma levels of noradrenaline and overnight urinary adrenaline levels, whereas their cortisol levels tended to be lower as compared to the low-symptom group. The plasma noradrenaline/cortisol ratio was higher among the high-symptom subjects. However, upon controlling for neuroticism and life style factors (smoking and alcohol consumption), all but the effects on cortisol failed to meet significance criteria. Higher stress load was associated with higher plasma adrenaline responses during the laboratory session, irrespective of neuroticism or life-style measures. These results therefore suggest that in addition to measuring exposure to real-life stressors, it is also necessary to measure outcomes, such as symptoms, and to be aware of the effects of neuroticism and life-style when attempting to understand which specific psychosocial factors effect psychoendocrinological functioning.

Predictors for altering caffeine consumption during stress.

The present study investigated whether or not those who self-report increasing use of caffeine when under stress consume caffeine more for the drug (e.g., stimulant) effects. A three-part questionnaire assessing demographic information, caffeine use patterns, and reasons for use was completed by 182 females and 106 males (mean age, 22.4 years; range, 9 to 59). Consistent with earlier research, nearly 50% of the sample reported increasing consumption of coffee or soft drinks when under stress. Hierarchical multiple regression analyses showed drinking for relief reasons as the most consistent predictor for altering caffeine use when under stress. Understanding differences in use patterns will likely help strengthen the ability to describe the extent to which caffeine use contributes to cardiovascular and other disorders.

The effects of stress and coping on daily alcohol use in women.

To evaluate the notion that perceived stress and drinking covary over time, daily logs were periodically collected over a 6-month period from 32 middle-aged women. Results indicated that significantly less alcohol was consumed on high-stress weeks than low-stress weeks. Problem-focused (P-F) coping preference moderated this relationship, with low P-F copers consuming more alcohol per occasion than did high P-F copers but only during low-stress weeks. These findings support a model of stress and alcohol use that includes coping preference as an important moderator of women's drinking. In addition, our data are consistent with the notion that stress can influence alcohol consumption but that low P-F women regulate their use, preferring to delay their drinking until after the termination of the stressor.

Cardiovascular reactivity, mood, and task performance in deprived and nondeprived coffee drinkers.

Forty habitual, heavy coffee drinkers (M = 5.7 cups/day) participated in two experimental sessions. Participants were deprived of their morning coffee for one of the laboratory sessions, not deprived the other. During each session, subjects consumed 12 oz of caffeinated coffee, decaffeinated coffee, or caffeine-free herbal tea. Measurements of heart rate, blood pressure, mood, and catecholamine response to deprivation and consumption of the beverage, alone and in combination with challenging tasks, were made. This study found that caffeine continues to cause blood pressure increases with chronic, heavy consumption and that these effects do not appear to habituate with regular use. Subjects reacted to behavioral challenge with fewer negative mood effects if they had consumed caffeine or coffee. Mild caffeine deprivation was associated with symptoms of stress.

Issues in psychoneuroimmunology research.

Careful design of studies is crucial for meaningful progress in this area of inquiry. Along with systematic evaluation of immunologic factors, clear understanding of antecedent factors is also important. Age, sex, and other sociodemographic factors might play a major role in how an individual reacts to a given situation when compared with another individual. Assessment of the impact of these factors on the immune system might be further complicated by immunosuppressive viruses like HIV or by the use of many common medications such as beta-blockers for hypertension (Kiecolt-Glaser & Glaser, 1988). Longitudinal studies are needed to understand the process of change and the dynamic patterning of psychosocial and immunologic relationships over time. Additionally, use of multimodal measures to assess psychological events such as stress is imperative (Baum, Grunberg, & Singer, 1982). It will not serve our understanding of psychological influences on the immune system to jump to the conclusion that an event is "stressful" because it seems as if it should be. Finally, establishing a "core" battery of widely accepted immune tests will be important in establishing comparability across studies. The standardization and acceptance of specific biochemical measures will facilitate the infusion of talented clinical and basic scientists into the area of psychoneuroimmunology.