Alzheimer Centrum Limburg, School for Mental Health and Neuroscience, Maastricht University, Maastricht, the Netherlands.
Department of Behavioural Science and Health, University College London, London, UK.
J Alzheimers Dis. 2019;71(2):549-557. doi: 10.3233/JAD-190541.
Differences in dementia risk across the gradient of socioeconomic status (SES) exist, but their determinants are not well understood.
This study investigates whether health conditions and lifestyle-related risk factors explain the SES inequalities in dementia risk.
6,346 participants from the English Longitudinal Study of Ageing were followed up from 2008/2009 until 2014/2015. We used Cox regression adjusted for age, gender, wealth/education, and clustering at the household level to examine the association between SES markers (wealth, education) and time to dementia in a structural equation model including potential mediation or effect modification by a weighted compound score of twelve modifiable risk and protective factors for dementia ('LIfestyle for BRAin health' (LIBRA) score).
During a median follow-up of 6 years, 192 individuals (3.0%) developed dementia. LIBRA scores decreased with increasing wealth and higher educational level. A one-point increase in the LIBRA score was associated with a 13% increase in dementia risk (hazard ratio (HR) = 1.13, 95% confidence interval 1.07-1.19). Higher wealth was associated with a decreased dementia risk (HR = 0.58, 0.39-0.85). Mediation analysis showed that 52% of the risk difference between the highest and lowest wealth tertile was mediated by differences in LIBRA (indirect effect: HR = 0.75, 0.66-0.85). Education was not directly associated with dementia (HR = 1.05, 0.69-1.59), but was a distal risk factor for dementia by explaining differences in wealth and LIBRA scores (indirect effect high education: HR = 0.92, 0.88-0.95).
Socioeconomic differences in dementia risk can be partly explained by differences in modifiable health conditions and lifestyle factors.
在社会经济地位（SES）梯度上，痴呆风险存在差异，但这些差异的决定因素尚不清楚。
本研究旨在探讨健康状况和与生活方式相关的风险因素是否可以解释痴呆风险的 SES 不平等。
6346 名来自英国老龄化纵向研究的参与者从 2008/2009 年开始随访，直至 2014/2015 年。我们使用 Cox 回归调整年龄、性别、财富/教育以及家庭层面的聚类，在包含 12 种可修改的痴呆风险和保护因素（“生活方式对大脑健康”（LIBRA）评分）的加权复合评分的结构方程模型中，研究 SES 标志物（财富、教育）与痴呆时间的关系。
在中位随访 6 年期间，192 人（3.0%）发生痴呆。LIBRA 评分随财富和教育程度的增加而降低。LIBRA 评分增加一个单位，痴呆风险增加 13%（危险比（HR）=1.13，95%置信区间 1.07-1.19）。较高的财富与痴呆风险降低相关（HR=0.58，0.39-0.85）。中介分析表明，最高和最低财富三分位数之间的风险差异有 52%是由 LIBRA 差异介导的（间接效应：HR=0.75，0.66-0.85）。教育程度与痴呆无直接关联（HR=1.05，0.69-1.59），但通过解释财富和 LIBRA 评分的差异，成为痴呆的间接危险因素（间接效应高教育程度：HR=0.92，0.88-0.95）。
痴呆风险的 SES 差异可以部分解释为可改变的健康状况和生活方式因素的差异。
