Note. Inflammation index is the sum of the positive indicators of systemic inflammation including high C-reactive protein (> 3.0 mg/dL), high fibrinogen (highest quartile), and low urinary albumin (≤ 3.5 μg/mL) and ranges 0–3.47 Predicted values from an ordinal logistic model are presented, adjusting for race, education, family income, marital status, obesity, alcohol use, chronic illnesses, and metabolic syndromes.
The second example further shows how differential exposures and vulnerabilities to social behavioral risk factors can contribute to sex differences in physiological determinants of health and longevity and their age variations. Using the NHANES III data, we found that the associations between social integration and physiological dysregulation differ by sex and age. Figure 3 shows that lack of religious attendance, in particular, is associated with more inflammation and higher probabilities of metabolic syndrome in men than women and in the older than the younger age group. It is also associated with higher allostatic load or more cumulative physiological dysregulation in older adults. These results are largely consistent with the observation that socially isolated older men are particularly more vulnerable to disease and mortality, and hence, suggest specific biophysiological mechanisms by which social relations are associated with health and sex and age heterogeneity therein.49 These examples suggest the interconnections between measures of 2 domains of explanatory factors, social and biological, that have been commonly examined in studies of health. They also show the value of considering age. The next step is to reveal the precise mechanisms, including the role of relevant gene activities or possible epigenetic changes, through which such interconnections translate into gender differences in health over the life course.