A Binational Study to Understand Dementia Risk and Disparities of Mexican Americans: The Role of Migration and Social Determinants

总结 墨西哥裔美国人占美国人口的大多数， (US)拉丁裔。与非拉丁美洲人相比，墨西哥裔美国人经历了大量的社会劣势 美国的白人，包括较低的教育，较低的社会经济地位，和移民相关的压力。 尽管持续的劣势，有限的可用证据表明，墨西哥裔美国人表现出 痴呆症发病率与非拉丁裔白人相似。墨西哥裔美国人意想不到的健康优势 还观察到许多其他健康结果。选择性移民，来自墨西哥的健康人 美国和不健康的成年人返回墨西哥的移民，是墨西哥人的主要解释。 美国健康优势几个已知的痴呆症风险因素也是从老年人迁移到老年人的预测因素。 墨西哥到美国。然而，没有任何工作量化了选择性移民及其对移民的偏见。 墨西哥裔美国人和非拉丁裔白人在痴呆症风险方面的比较。因此有 不知道在校正选择性痴呆后，墨西哥裔美国人是否存在痴呆风险差异。 迁移在这项研究中，我们建议将来自两个协调的、具有全国代表性的队列的联合收割机数据结合起来， 50岁以上的成年人：美国健康和退休研究（HRS，n = 26，690，包括2，452名墨西哥裔美国人） 墨西哥健康与老龄化研究（MHAS，n = 13，798）。这些队列包括统一的纵向 与痴呆风险密切相关的认知指标。选择性迁移的原因几乎 不可能只有美国的数据。结合来自墨西哥和美国队列的数据，我们包括了 移民和非移民，使我们能够测试痴呆症风险和主要因素是否存在差异 在解释了移民模式后，墨西哥裔美国人的痴呆风险增加。这项两国研究将 允许我们（目标1）量化从墨西哥到美国的选择性移民和返回墨西哥的移民， 已确定的儿童和成人痴呆症风险因素可能影响移民模式。我们将 然后创建"迁移倾向"评分。这个分数将采用新的方法来评估贡献 社会因素对选择性移民偏见的影响，基于对墨西哥国内相对社会地位的评估， 在墨西哥出生的美国人、在美国出生的墨西哥裔美国人和在美国出生的非拉丁裔白人，而不是直接 比较具有相同绝对社会地位的人。使用这个分数来解释选择偏差，我们将 显示了墨西哥裔美国人与美国非拉丁裔人相比痴呆风险的（目标2）差异幅度 与移民到美国的人相比， 留在墨西哥。社会经济因素与墨西哥裔美国人健康之间的联系尚不确定， 我们将（目标4）确定教育、家庭和邻里劣势以及歧视对 墨西哥裔美国人的痴呆风险，占选择性移民。这项研究将提供关键的 关于痴呆症的风险在这个不断增长的美国人口和其他弱势群体或移民群体的信息。

Summary Little is known about dementia disparities for Mexican Americans, who comprise the majority of United States (US) Latinos. Mexican Americans experience substantial social disadvantages compared with non-Latino whites in the US, including lower education, lower socioeconomic status, and migration-related stressors. Despite sustained disadvantage, the limited available evidence suggests that Mexican Americans exhibit similar rates of dementia as non-Latino whites. Unexpected health advantages of Mexican Americans have also been observed for many other health outcomes. Selective migration, both of healthy people from Mexico to the US and return migration of unhealthy adults back to Mexico, is a leading explanation for the Mexican American health advantage. Several known risk factors for dementia are also predictors of migration from Mexico to the US. However, no work has quantified selective migration and the bias it introduces to the comparison between Mexican American and non-Latino whites with respect to dementia risk. Therefore, it is unknown whether a dementia risk disparity exists for Mexican Americans after correcting for selective migration. In this study, we propose to combine data from two harmonized, nationally representative cohorts of adults aged 50+: the US Health and Retirement Study (HRS, n=26,690, including 2,452 Mexican Americans) and the Mexican Health and Aging Study (MHAS, n=13,798). These cohorts include harmonized longitudinal cognitive measures that are robustly linked to dementia risk. Accounting for selective migration is almost impossible with US-only data. Combining data from a Mexico- and a US- based cohort, we include both migrants and non-migrants, allowing us to test whether there are disparities in dementia risk and major factors driving dementia risk in Mexican Americans after accounting for migration patterns. This binational study will allow us to (Aim 1) quantify selective migration from Mexico to the US and return migration to Mexico as a function of established childhood and adult dementia risk factors that may influence migration patterns. We will then create a “propensity to migrate” score. This score will adopt a new approach to evaluating the contribution of social factors to selective migration bias, based on evaluating relative social position within Mexican Americans born in Mexico, US-born Mexican Americans, and US-born non-Latino whites, rather than directly comparing people with the same absolute social position. Using this score to account for selection bias, we will show the magnitude of (Aim 2) differences in dementia risk comparing Mexican Americans to US non-Latino whites and (Aim 3) differences in dementia risk associated with migration to the US, compared to people who remained in Mexico. The link between socioeconomic factors and health in Mexican Americans is uncertain, so we will (Aim 4) identify effects of education, household and neighborhood disadvantage, and discrimination on dementia risk of Mexican Americans, accounting for selective migration. This study will provide critical information about dementia risk in this growing US population and other disadvantaged or immigrant groups.