Regional Epidemiology Unit, ASL TO3 Piedmont Region, Via Sabaudia 164, 10095 Grugliasco, Turin, Italy.
Soc Sci Med. 2012 Mar;74(6):897-906. doi: 10.1016/j.socscimed.2011.10.045. Epub 2012 Jan 17.
North-western Italy has a long history of domestic influx, however little is known on how migrant mortality compares to mortality at the local level. While geographic mortality gradients may play a role, conceptualizations developed for international migration may also be relevant. Using this theoretical framework, the study investigated immigrant-native differentials in the north-western city of Turin through a 34-year follow-up that was facilitated by the Turin Longitudinal Study. The study population comprised inhabitants of age 30-74 years at the 1971 census. Survival trajectories were modelled through the Gompertz distribution and were examined for nativity status, birthplace, length of stay and age at arrival (the last two variables were combined). All estimates were adjusted for socio-economic factors. Overall, the risk of dying for internal migrants was lower, compared to locals, and consistent with geographic gradients. However, this pattern hid significant differences mediated by both age at arrival and length of stay. The advantage appeared to be exclusive to young and adult migrants, despite differentials narrowing over time. Immigrants who arrived after age 44 suffered instead a progressively greater excess risk, compared to natives, as residence increased. The dissipation of the health advantage found in internal migrants, along with poor health outcomes amongst people older at arrival, raises concern about immigrants from developing countries who need to endure a more demanding journey and adjustment to the new environment. The study indicated, through lengthy longitudinal data, that immigrant-native differentials were best explained by the stratified variable 'length of stay by age at arrival' and this should inform future studies.
意大利西北部有着长期的国内人口流动历史，但对于移民死亡率与当地死亡率的比较，我们知之甚少。虽然地理死亡率梯度可能起作用，但为国际移民制定的概念也可能相关。利用这一理论框架，该研究通过都灵纵向研究（Turin Longitudinal Study）进行了为期 34 年的随访，调查了意大利西北部城市都灵的移民与本地人之间的差异。研究人群包括 1971 年普查时年龄在 30-74 岁之间的居民。通过使用 Gompertz 分布对生存轨迹进行建模，并对出生国、出生地、逗留时间和到达年龄（后两个变量结合在一起）进行了检查。所有估计值都根据社会经济因素进行了调整。总体而言，与本地人相比，内部移民的死亡风险较低，这与地理梯度一致。然而，这种模式掩盖了由到达年龄和逗留时间共同介导的显著差异。尽管差异随着时间的推移而缩小，但这种优势似乎只适用于年轻和成年移民。相比之下，44 岁以后到达的移民随着居住时间的增加，其死亡风险逐渐增加，与本地人相比存在越来越大的超额风险。在内部移民中发现的健康优势逐渐消失，以及到达年龄较大的人的健康状况较差，这引起了人们对来自发展中国家的移民的关注，他们需要经历更艰难的旅程和适应新环境。这项研究通过长期的纵向数据表明，移民与本地人之间的差异最好通过“到达年龄的逗留时间”这一分层变量来解释，这应该为未来的研究提供信息。
