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, appraisals, and mood may be important in understanding psychological and immune responses to stress. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

How does optimism suppress immunity? Evaluation of three affective pathways.

Studies have linked optimism to poorer immunity during difficult stressors. In this study, when 1st-year law students (N = 46) relocated to attend law school, reducing conflict among curricular and extracurricular goals, optimism predicted larger delayed-type hypersensitivity responses, indicating more robust in vivo cellular immunity. However, when students did not relocate, increasing goal conflict, optimism predicted smaller responses. Although this effect has been attributed to negative affect when difficult stressors violate optimistic expectancies, distress did not mediate optimism's effects on immunity. Alternative affective mediators related to engagement--engaged affect and fatigue--likewise failed to mediate optimism's effects, although all 3 types of affect independently influenced in vivo immunity. Alternative pathways include effort or self-regulatory depletion. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The structure and health correlates of trait repetitive thought in older adults.

Repetitive thought (RT) involves frequent or prolonged thoughts about oneself and one's world, encompassing discrete forms such as trait worry, rumination, processing, and reminiscing. These forms of RT can be described using 3 basic, underlying qualities: total propensity for RT of all types, valence (positive vs. negative content), and purpose (searching or uncertainty vs. solving or certainty). The adaptiveness of discrete forms with regard to health is likely to be related to these qualities, particularly valence and total propensity. The present study confirmed the model and identified the relationship of these qualities of RT to subjective psychological, physical, and cognitive health in older adults aged 60–94 (N = 179). As predicted, more negatively valenced trait RT was associated with worse psychological, physical, and cognitive health. More total propensity for RT was associated only with worse psychological health. Searching purpose was associated only with worse cognitive health. In turn, negatively valenced RT was predicted by poorer executive functions, suggesting that such functions may be important for directing this quality of RT. The valence of older adults' RT is important insofar as it may contribute to their sense of good or ill health. However, the propensity for all kinds of RT to associate with poorer psychological health may reflect the co-occurrence of negative and positive RT, such as rumination and emotional processing. Although RT has not been extensively investigated in older adults, it appears to play an important role in their subjective health. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

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. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Psychological Stress and the Human Immune System: A Meta-Analytic Study of 30 Years of Inquiry.

The present report meta-analyzes more than 300 empirical articles describing a relationship between psychological stress and parameters of the immune system in human participants. Acute stressors (lasting minutes) were associated with potentially adaptive upregulation of some parameters of natural immunity and downregulation of some functions of specific immunity. Brief naturalistic stressors (such as exams) tended to suppress cellular immunity while preserving humoral immunity. Chronic stressors were associated with suppression of both cellular and humoral measures. Effects of event sequences varied according to the kind of event (trauma vs. loss). Subjective reports of stress generally did not associate with immune change. In some cases, physical vulnerability as a function of age or disease also increased vulnerability to immune change during stressors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cigarette mentholation increases smokers' exhaled carbon monoxide levels.

12 male smokers participated in 3 controlled-dose smoking sessions spaced 1 wk apart. In each session, Ss inhaled 1,200 cc of cigarette smoke. Menthol dosage varied across sessions, such that Ss smoked experimental cigarettes that had been injected with 0, 4, or 8 mg of menthol. Exhaled CO levels increased concomitantly with menthol dosage. There were no differences in smoking topography across the 3 conditions. The ability of menthol to increase the toxicity of cigarette smoke by raising CO levels is discussed. Results suggest that menthol cigarette preference may account for some of the racial differences in smoking behavior and smoking-related outcomes found in past literature. (PsycINFO Database Record (c) 2010 APA, all rights reserved)