Ruiz Milagros, Hu Yaoyue, Martikainen Pekka, Bobak Martin
School of Health and Social Care, University of Essex, Colchester, UK.
Research Department of Epidemiology and Public Health, University College London, London, UK.
Innov Aging. 2023 Jun 26;7(6):igad064. doi: 10.1093/geroni/igad064. eCollection 2023.
Cross-national research on cognitive aging inequality has largely concentrated on Western countries. It is unclear whether socioeconomic position (SEP) has similar effects on cognitive decline in emerging economies. We compared the association between life course SEP and cognitive function trajectories between China and England, the largest nation under state socialism and one of the oldest capitalist countries.
This cross-cohort study examined participants aged 50 years and older from the China Health and Retirement Longitudinal Study ( = 12,832) and the English Longitudinal Study of aging ( = 8,875). Cognition -scores were derived using comparable measures of memory and time orientation on 4 occasions. Life course SEP was self-reported by participants at baseline. Seven- to 8-year trajectories of cognition -scores were estimated using latent growth curve modeling. Country- and gender-specific associations between childhood/adolescent deprivation, education, material wealth, and home ownership were evaluated in relation to model intercept (baseline level) and linear slope (annual rate of change) of cognition.
After multivariable adjustment, education was positively associated with the greatest differences in baseline cognition across country and gender. Education was further linked to a slower rate of cognitive decline (-score units per year); but compared with those with low education, Chinese men ( = 0.032) and women ( = 0.065) with high education had significantly slower declines than English men ( = -0.004) and women ( = 0.010) with high education.
Despite substantial between-cohort differences in downstream and upstream determinants of dementia, education provided the greatest benefits to cognitive aging in England but particularly in China.
关于认知衰老不平等的跨国研究主要集中在西方国家。目前尚不清楚社会经济地位（SEP）在新兴经济体中对认知衰退是否有类似影响。我们比较了中国（最大的社会主义国家）和英国（最古老的资本主义国家之一）生命历程SEP与认知功能轨迹之间的关联。
这项跨队列研究考察了来自中国健康与养老追踪调查（n = 12,832）和英国老龄化纵向研究（n = 8,875）的50岁及以上参与者。认知z分数是通过在4个时间点对记忆和时间定向的可比测量得出的。生命历程SEP由参与者在基线时自我报告。使用潜在增长曲线模型估计了7至8年的认知z分数轨迹。评估了儿童期/青少年期贫困、教育、物质财富和住房所有权在国家和性别层面与认知模型截距（基线水平）和线性斜率（年变化率）之间的关联。
经过多变量调整后，教育与国家和性别层面基线认知的最大差异呈正相关。教育还与较慢的认知衰退速度相关（每年的z分数单位）；但与低教育水平者相比，中国高教育水平的男性（β = 0.032）和女性（β = 0.065）的认知衰退明显慢于英国高教育水平的男性（β = -0.004）和女性（β = 0.010）。
尽管痴呆症的下游和上游决定因素在队列之间存在很大差异，但教育对英国尤其是中国的认知衰老有最大益处。
