native-born population. When older cohorts are compared, the groups reflect both selection from the original birth cohorts and differences in survival. Socioeconomic factors—education, income, wealth, occupational status, even residential neighborhood—are also important. Not only does low socioeconomic status impair health, but illness can in turn impose costs and reduce earnings and wealth. Yet the processes by which socioeconomic status affects health are not well understood. Furthermore, socioeconomic status is not always the dominant factor: for example, despite higher poverty rates, Hispanics have lower age-adjusted mortality rates than whites, and relatively low-income Vietnamese have lower mortality rates than relatively high-income Asian Indians.
Behavior risk factors—such as smoking, overeating, lack of exercise, and excessive alcohol use—clearly impair health, but their contribution to racial and ethnic differences is not always what one might expect. These risk factors are less common among Asians than whites (except for less exercise), which is consistent with better Asian health. However, they are more common among Hispanics than whites, despite lower Hispanic mortality. And because blacks generally smoke less than whites, this critical risk factor for several causes of death and illness serves to reduce differences between blacks and whites rather than increase them.
Cumulative prejudice and discrimination have been hypothesized to contribute to health differences among groups, but the processes by which they might do so are not well understood. Some evidence suggests that being discriminated against leads to psychological distress, with such negative health effects as elevated blood pressure, but not all studies support this finding.
Levels of stress, not only from experiencing discrimination but also from other pressures of life, are hypothesized to contribute to poor health, and they may vary across racial and ethnic groups. Models of the effects of stress on health such as allostatic load, cardiovascular reactivity, psychoneuroimmunology, metabolic syndrome, and neurovisceral integration may have different predictive value among older persons of different racial and ethnic groups.
Differences in health care access and quality are well documented, and they may affect health, but how much of the racial and ethnic health differences may be accounted for by such differences in health care is unclear. Quality of health care varies geographically, and some of this variation may be related to the racial and ethnic composition of an area. Stereotypes held by providers have been hypothesized to be important, but the effects of such stereotypes on health differences in older ages is unclear. Patient compliance may account for some of the observed differences, and compliance varies by socioeconomic status, yet the patterns across racial and ethnic groups are not consistent.