摘要：Objectives. We examined changes in socioeconomic status (SES) and Black to White inequalities in HIV/AIDS mortality in the United States before and after the introduction of highly active antiretroviral therapy (HAART). Methods. Taking a fundamental cause perspective, we used negative binomial regression to analyze trends in county-level gender-, race-, and age-specific HIV/AIDS mortality rates among those aged 15 to 64 years during the period 1987–2005. Results. Although HIV/AIDS mortality rates decreased once HAART became available, the declines were not uniformly distributed among population groups. The associations between SES and HIV/AIDS mortality and between race and HIV/AIDS mortality, although present in the pre-HAART period, were significantly greater in the peri- and post-HAART periods, with higher SES and White race associated with the greatest declines in mortality during the post-HAART period. Conclusions. Our findings support the fundamental cause hypothesis, as the introduction of a life-extending treatment exacerbated inequalities in HIV/AIDS mortality by SES and by race. In addition to a strong focus on factors that improve overall population health, more effective public health interventions and policies would facilitate an equitable distribution of health-enhancing innovations. As evidenced by the goals explicitly stated in Healthy People 2010 , the sizeable and persistent health disparities in the United States are an area of tremendous concern. 1 In 2005, all-cause age-adjusted mortality among persons aged 25 to 64 years with fewer than 12 years of education was 215% higher than it was among those in the same age group with 13 or more years of education. 2 In 2005, all-cause age-adjusted mortality rates of Blacks in the United States exceeded those of Whites by 29%. 2 In the context of these broader disparities, HIV/AIDS disproportionately affects disadvantaged individuals and racial minorities. In 2005, the age-adjusted HIV/AIDS mortality rate per 100 000 population was 782% greater among Blacks (19.4) than it was among Whites (2.2). 3 As defined by Braveman, a health inequality or disparity is a difference in which disadvantaged social groups—such as the poor, racial/ethnic minorities, women, or other groups who have persistently experienced social disadvantage or discrimination—systematically experience worse health or greater health risks than more advantaged social groups. 4 (p167) Identifying health inequalities and understanding their root causes are essential prerequisites for eliminating disproportionate disease burdens and achieving health equity across disparate groups. Although the presence of health inequalities across socioeconomic status (SES) and racial/ethnic divisions in the United States is widely acknowledged, further research is needed to identify ways to prevent their occurrence and ameliorate them once entrenched. 3 We examined the extent to which SES and racial inequalities in HIV/AIDS mortality in the United States have emerged over time and explore the fundamental cause hypothesis as a contributing explanation for such trends. 5 The fundamental social causes theory was developed to explain why social conditions like SES are so reliably associated with mortality across time and place. The association was present in Mulhouse, France, in the early 1800s; Rhode Island in 1865; Chicago, Illinois, in the 1930s; and it occurs in Europe and the United States today. 6 – 10 Given the vast differences in life expectancy, risk factors, diseases, and health care systems characterizing these places and times, the persistence of the SES–mortality association is remarkable. According to fundamental cause theory, mortality follows the SES gradient in a predictable pattern under dissimilar circumstances because SES embodies access to resources—knowledge, money, power, prestige, and beneficial social connections—that can be used in different places and at different times to confer a significant health advantage. The flexible utility of these resources enables the SES–mortality association to emerge in situations with disparate health conditions. For a more complete exposition of the conceptual approach, see Phelan et al. 11 and Link and Phelan. 5 Fundamental social cause theory asserts that as we learn more about how to prevent or treat diseases, the benefits of this new knowledge are not distributed equally throughout the population but are harnessed more securely by those who are less likely to be exposed to discrimination and who have greater access to knowledge, money, power, prestige, and beneficial social connections. This triggers the formation or exacerbation of health inequalities along typical social cleavages such as SES and race. 5 Fundamental social cause theory makes a specific prediction about social inequalities in HIV/AIDS mortality before and after the development and dissemination of highly active antiretroviral therapy (HAART). SES-related resources and racial discrimination are likely to be important at multiple stages in the procurement of life-saving antiretroviral medications. Examples of mechanisms through which SES and race may affect HIV/AIDS mortality are knowing about treatment, living near a location where treatment is provided, having access to health care, receiving the correct diagnosis and optimal treatment upon consulting medical professionals, gaining support to follow through with treatment, and being encouraged by medical teams that interact with people of lower social status equitably and respectfully. We examined SES and racial inequalities in HIV/AIDS mortality in light of major advances in the capacity to delay death, primarily because of the introduction of HAART following the approval of protease inhibitors by the US Food and Drug Administration in December 1995 12 and March 1996. 13 , 14 Use of HAART has specifically been linked to declines in morbidity and mortality among persons with HIV/AIDS. 15 The fundamental cause hypothesis suggests that these improvements, although they benefit all groups, will benefit persons of high SES and Whites more than they will persons of low SES and Blacks, thereby creating or exacerbating health inequalities over time. To test the fundamental cause hypothesis, we analyzed trends in county-level HIV/AIDS-specific mortality rates among Black men, White men, Black women, and White women over a 20-year period before, during, and after the introduction of HAART from late 1995 through early 1996. We hypothesized that (1) the association between time and HIV/AIDS mortality would be nonlinear, rising before the introduction of HAART and dropping precipitously after its introduction; (2) the association between SES and HIV/AIDS mortality would be significantly greater during the peri- and post-HAART periods than during the pre-HAART period; and (3) the association between race and HIV/AIDS mortality would be significantly greater during the peri- and post-HAART periods than during the pre-HAART period.
