From the Department of Public Health, University of Otago, Wellington, New Zealand.
Laboratory of Psychiatric Biostatistics, Department of Psychiatry, McLean Hospital/Harvard Medical School, Harvard, MA.
Epidemiology. 2018 Jul;29(4):506-516. doi: 10.1097/EDE.0000000000000842.
Racial/ethnic inequalities in mortality may be reducible by addressing socioeconomic factors and smoking. To our knowledge, this is the first study to estimate trends over multiple decades in (1) mediation of racial/ethnic inequalities in mortality (between Māori and Europeans in New Zealand) by socioeconomic factors, (2) additional mediation through smoking, and (3) inequalities had there never been smoking.
We estimated natural (1 and 2 above) and controlled mediation effects (3 above) in census-mortality cohorts for 1981-1984 (1.1 million people), 1996-1999 (1.5 million), and 2006-2011 (1.5 million) for 25- to 74-year-olds in New Zealand, using a weighting of regression predicted outcomes.
Socioeconomic factors explained 46% of male inequalities in all three cohorts and made an increasing contribution over time among females from 30.4% (95% confidence interval = 18.1%, 42.7%) in 1981-1984 to 41.9% (36.0%, 48.0%). Including smoking with socioeconomic factors only modestly altered the percentage mediated for males, but more substantially increased it for females, for example, 7.7% (5.5%, 10.0%) in 2006-2011. A counterfactual scenario of having eradicated tobacco in the past (but unchanged socioeconomic distribution) lowered mortality for all sex-by-ethnic groups and resulted in a 12.2% (2.9%, 20.8%) and 21.2% (11.6%, 31.0%) reduction in the absolute mortality gap between Māori and Europeans in 2006-2011, for males and females, respectively.
Our study predicts that, in this high-income country, reducing socioeconomic disparities between ethnic groups would greatly reduce ethnic inequalities in mortality over the long run. Eradicating tobacco would notably reduce ethnic inequalities in absolute but not relative mortality.
通过解决社会经济因素和吸烟问题，可能会减少种族/民族间的死亡率差异。据我们所知，这是第一项研究，旨在估计在以下方面的趋势：（1）社会经济因素对毛利人和欧洲人在新西兰的死亡率差异的中介作用（2）通过吸烟的额外中介作用，以及（3）如果没有吸烟，这些差异会是什么样子。
我们使用回归预测结果的加权法，对 1981-1984 年（110 万人）、1996-1999 年（150 万人）和 2006-2011 年（150 万人）期间，25 至 74 岁的新西兰人口普查死亡率队列，估计了自然（上述 1 和 2）和控制中介效应（上述 3）。
社会经济因素解释了所有三个队列中男性不平等的 46%，并且随着时间的推移，在女性中，这种贡献也在增加，从 1981-1984 年的 30.4%（95%置信区间=18.1%，42.7%）增加到 41.9%（36.0%，48.0%）。将社会经济因素与吸烟因素结合起来，对男性的中介百分比影响不大，但对女性的影响要大得多，例如，2006-2011 年的 7.7%（5.5%，10.0%）。如果过去（但社会经济分布不变）消除烟草，所有性别和种族群体的死亡率都会降低，2006-2011 年毛利人和欧洲人之间的绝对死亡率差距将分别减少 12.2%（2.9%，20.8%）和 21.2%（11.6%，31.0%）。
我们的研究预测，在这个高收入国家，从长远来看，减少族裔群体之间的社会经济差距将大大减少族裔间的死亡率差异。消除烟草将显著降低绝对但不会降低相对死亡率的种族差异。
