Gugushvili Alexi, Wiborg Øyvind Nicolay
Department of Sociology and Human Geography, University of Oslo, Moltke Moes vei 31, Harriet Holters Hus, N-0851, Oslo, Norway.
Lancet Reg Health Eur. 2024 Nov 8;48:101113. doi: 10.1016/j.lanepe.2024.101113. eCollection 2025 Jan.
In recent decades, we have observed rising wealth inequality while the pace of growth of life expectancy has slowed in many Western welfare democracies. There is scarce evidence, however, on links between wealth and mortality. The main methodological limitation in this area of scholarship is its inability to account for individuals' unobserved heterogeneity, such as personality and genetic factors, which could potentially affect both their wealth level and survival probabilities. This study aims to explore how wealth is linked to mortality risk in late-middle age, providing insights into the broader implications of socioeconomic status on health outcomes.
In this study, we use high-quality register data on wealth and mortality for the entire population of Norway, one of the world's most advanced welfare states with a low income inequality level but a highly uneven distribution of wealth. We address some of the main methodological constraints of the previous research by exploring if wealth at the age of 37-38 predicts mortality up to age 62. The research design employed mitigates the problem of unobserved heterogeneity by using sibling and twin fixed-effects models.
Both Kaplan-Meier survival analyses and the Cox proportional hazard regression results suggest that wealth is an important predictor of mortality even after individuals' observed and unobserved characteristics are accounted for with hazard ratios of 2.39 [95% confidence interval, CI 2.02, 2.83] among men and 1.74 [95% CI 1.39, 2.16] among women for the inverted cumulative density rank coefficients. The most disadvantaged groups are non-partnered men and women at the lower end of wealth distribution. Twin analyses align with the findings for the general population, indicating that wealth's effect on mortality is not confounded by genetic or shared family background factors.
Our findings suggest that wealth is an important predictor of mortality, even in an advanced welfare state with comprehensive healthcare provisions, highlighting the need to address inequalities in wealth distribution to improve population health outcomes.
The Research Council of Norway.
近几十年来，我们观察到财富不平等现象加剧，而在许多西方福利民主国家，预期寿命的增长速度有所放缓。然而，关于财富与死亡率之间的联系，证据却很少。该领域学术研究的主要方法局限性在于无法解释个体未被观察到的异质性，如个性和遗传因素，这些因素可能会同时影响他们的财富水平和生存概率。本研究旨在探讨财富与中年后期的死亡风险之间的联系，为社会经济地位对健康结果的更广泛影响提供见解。
在本研究中，我们使用了挪威全体人口的高质量财富和死亡率登记数据，挪威是世界上最发达的福利国家之一，收入不平等程度较低，但财富分布极不均衡。我们通过探究37 - 38岁时的财富是否能预测62岁之前的死亡率，来解决先前研究中的一些主要方法限制。所采用的研究设计通过使用兄弟姐妹和双胞胎固定效应模型，减轻了未被观察到的异质性问题。
卡普兰 - 迈耶生存分析和考克斯比例风险回归结果均表明，即使在考虑了个体观察到的和未观察到的特征后，财富仍是死亡率的重要预测因素。对于反向累积密度等级系数，男性的风险比为2.39[95%置信区间，CI 2.02, 2.83]，女性为1.74[95%CI 1.39, 2.16]。最弱势的群体是财富分布低端的非伴侣男性和女性。双胞胎分析与总体人群的研究结果一致，表明财富对死亡率的影响不受遗传或共同家庭背景因素的混淆。
我们的研究结果表明，即使在拥有全面医疗保健服务的发达福利国家，财富仍是死亡率的重要预测因素，这凸显了应对财富分配不平等以改善人群健康结果的必要性。
挪威研究理事会。
