UCLA

Background: The present four studies aimed to develop comprehensive, succinct measures of psychosocial resources and system-wide physiological dysregulation (allostatic load) and integrate these into a conceptual model, a modified form of the Reserve Capacity Model (Gallo & Matthews, 2003), to characterize how socioeconomic status, stress, psychosocial factors, mood, physiology, and health behaviors contribute to health outcomes.

Methods: Identification of factors underlying psychosocial resources was conducted in four independent samples in which a range of psychological and social resources were measured. A systematic review of psychosocial resources and allostatic load was conducted by retrieving all articles with "allostasis" or "allostatic load" in the title, abstract, or keywords from major databases. An allostatic load factor was examined using data from the large Midlife in the United States (MIDUS) study, which was also used for the final study linking SES, psychosocial resources, health behaviors, allostatic load, and a health outcome.

Results: In the first study, two factors, psychological and social resources, provided the best fit to all the psychosocial resources assessed. In Study 2, evidence of a common factor, allostatic load, underlying 23 biomarkers in MIDUS emerged, although there was also evidence of unique system-specific factors. In the systematic review of psychosocial resources and AL, results were mixed, with some studies finding null effects, and others finding significant positive or negative effects of psychosocial resources on allostatic load. In a fourth study testing the modified Reserve Capacity Model, results largely supported the model's predictions. SES was associated with better health outcomes indirectly via lower allostatic load, lower negative mood, and higher physical activity. These associations were themselves linked to SES via psychological resources and major stressful life events. Psychological resources were associated with higher physical activity, but not directly to allostatic load or health outcomes, and social resources had no association independent of psychological resources.

Conclusions: Psychological resources, social resources, and allostatic load form coherent constructs. Psychosocial resources appear more strongly associated with health behaviors than directly to allostatic load or health outcomes. Results generally supported the modified Reserve Capacity Model, suggesting it is a useful conceptual framework to guide future research.