Optimism, goal conflict, and stressor-related immune change.

Although optimism is usually conceptualized as a buffer against stressor-related changes in the immune system, some contradictory findings have emerged. The present research proposed that when facing conflicting goals, optimists are more likely to remain engaged with both goals and to experience higher short-term stress as a consequence. Optimists were therefore predicted to fare worse than pessimists immunologically when facing academic-social goal conflict but to fare better when not facing goal conflict. In the Study 1 sample (n = 48), optimism was associated with higher numbers of CD4+ cells among first-year law students who were less likely to have academic-social conflict and with lower numbers of CD4+ cells at midsemester among students who were more likely to have conflict. The results replicated in the Study 2 sample of law students (n = 22) using delayed-type hypersensitivity testing. Optimists may be subject to short-term physiological costs in their persistence to gain long-term rewards.

Personality and the immune system: models, methods, and mechanisms.

A relationship between personality and the immune system has been hypothesized for at least 25 years, and understanding this relationship could contribute to understanding how personality affects the onset and course of chronic diseases such as cancer and heart disease. A number of personality dimensions, including repression, optimism, hostility, attributional style, and extraversion-introversion, have been related to immune parameters or immunity. Theoretical and methodological issues in interpreting the extant literature and in planning future research include selection of personality dimensions to study, study design, and attention to potential psychosocial mediators. Past and future investigations using sophisticated theory and methodology to investigate the ongoing influence of personality on physiological systems, including the immune system, promise to advance the understanding of both.

Worry affects the immune response to phobic fear.

Worry, the cognitive enumeration and anticipation of potential future negative events, is associated with autonomic dysregulation, which may in turn have implications for the immune system. People endorsing high (n = 7) and normal levels of trait worry (n = 8) were briefly exposed to a phobic stimulus and the autonomic and immune responses and recovery were assessed. A time-matched control group (n = 6) was not exposed to any stimulus. Both worry groups showed increased heart rate and skin conductance in response to phobic fear. However, only the normal worry group showed a concomitant increase in natural killer cells in peripheral blood. Patterns of change during the follow-up period suggested that phobic fear had disrupted a normal circadian increase in natural killer cells. Adrenergic and hypothalamus-pituitary-adrenal mechanisms may be responsible for the differences between high and normal worry groups in their natural killer cell response to and recovery from phobic fear.

Relationship of worry to immune sequelae of the Northridge earthquake.

Worry is a cognitive activity in which potential problems are anticipated and enumerated in an attempt to control the future. Worry has been associated with dysregulation of the autonomic nervous system, which may extend to the immune system. The relationship between trait worry and immune parameters was investigated at three follow-up points after the Northridge earthquake in a sample of 47 hospital employees. Participants with scores above the median on a trait worry measure had fewer natural killer cells than participants with worry scores below the median and controls. This effect was not mediated by intrusive thoughts, avoidance, anxious mood, or health behavior. These results suggest that worry may have a detrimental effect on the regulation of natural killer cells during stress. This effect may be due to differences in autonomic responsiveness associated with worry.

Optimism is associated with mood, coping, and immune change in response to stress.

This study explored prospectively the effects of dispositional and situational optimism on mood (N = 90) and immune changes (N = 50) among law students in their first semester of study. Optimism was associated with better mood, higher numbers of helper T cells, and higher natural killer cell cytotoxicity. Avoidance coping partially accounted for the relationship between optimism and mood. Among the immune parameters, mood partially accounted for the optimism-helper T cell relationship, and perceived stress partially accounted for the optimism-cytotoxicity relationship. Individual differences in expectancies, appraisal, and mood may be important in understanding psychological and immune responses to stress.

Shaking up immunity: psychological and immunologic changes after a natural disaster.

OBJECTIVE: The 1994 Northridge earthquake created life disruption and psychological distress for employees of the nearby Sepulveda VA Medical Center. We were interested in the immunologic correlates of disruption and distress under these stressful circumstances. METHOD: Sixty-eight employees were examined beginning 11 days post-earthquake and were observed until about 4 months after the earthquake, during which time three psychological and immunologic assessments were done. Subjects experienced life disruption from the earthquake itself, damage to home and possessions, injury to self and others, and damage to and functional disruption of workplace. Questionnaires assessed degree of life disruption (personal and work-related), mood, earthquake-specific distress, and repression (alexithymia, coping style or "Type C", and "immunosuppression-prone" traits). Immune measures included lymphocyte subsets-total T (CD3+), helper T (CD4+), cytotoxic T (CD3 + CD8+), B (CD19+), and natural killer (NK; CD3 - CD16 + CD56+)-as well as lymphoid cell mitogenesis (PHA and PWM), and NK cell cytotoxicity. RESULTS: Along with a lessening degree of distress over time, a number of immunologic measures declined over the assessment period (CD3+, CD8+, CD16 + 56+ cells. T cell blastogenesis, and NK cell cytotoxicity). Furthermore, subjects reporting low distress had higher numbers of CD3+ and CD8+ cells and a higher proliferative response to PHA. Those with distress corresponding to life disruption had highest levels of CD3+ and CD8+ cells. Measures of repression did not relate directly to immunity. CONCLUSION: These results suggest that appropriateness of psychological reaction to the realistic degree of life stress was least disruptive of an aspect of immunity.

Causal attributions predict rate of immune decline in HIV-seropositive gay men.

Research has suggested that attributions-the perceived causes of events-may affect psychological and physical health and the immune system. The authors hypothesized that attributions reflecting negative beliefs about the self, the future, and control would affect helper T cell (CD4) decline and onset of AIDS in individuals with HIV, either directly or through associations with psychological states such as depression. HIV+ gay men (N = 86) participated in a structured interview from which causal attributions were extracted and coded. Attributing negative events to aspects of the self significantly predicted faster CD4 decline over 18 months following the interview, controlling for potential psychological, behavioral, social, and health mediators such as depression and health behavior. However, attributions did not predict AIDS diagnosis during the study period. The results support the idea that causal attributions related to beliefs about the self may have an influence on the immune system.