Laboratory of Epidemiology and Population Sciences, National Institutes on Aging, NIA/NIH/IRP, Baltimore, MD, USA.
Department of Research Programs, Fort Belvoir Community Hospital, Fort Belvoir, VA, US.
Transl Psychiatry. 2022 Nov 15;12(1):478. doi: 10.1038/s41398-022-02243-y.
Differential racial and socioeconomic disparities in dementia incidence across income groups and their underlying mechanisms remain largely unknown. A retrospective cohort study examining all-cause dementia incidence across income groups was conducted linking third National Health and Nutrition Examination Surveys (NHANES III) to Centers for Medicare and Medicaid Services-Medicare data over ≤26 y of follow-up (1988-2014). Cox regression and generalized structural equations models (GSEM) were constructed among adults aged≥60 y at baseline (N = 4,592). Non-Hispanic Black versus White (NHW) adults had higher risk of dementia in age and sex-adjusted Cox regression models (HR = 1.34, 95%CI: 1.15-1.55, P < 0.001), an association that was attenuated in the SES-adjusted model (HR = 1.15, 95%CI: 1.01-1.34, P = 0.092). SES was inversely related to dementia risk overall (per Standard Deviation, HR = 0.80, 95% CI:0.69-0.92, P = 0.002, Model 2), mainly within the middle-income group. Within the lowest and middle-income groups and in socio-economic status (SES)-adjusted models, Mexican American participants were at lower all-cause dementia risk compared with their NHW counterparts. GSEM models further detected 3 pathways explaining >55% of the total effect of SES on dementia risk (Total effect = -0.160 ± 0.067, p = 0.022), namely SES→LIFESTYLE→DEMENTIA (Indirect effect (IE) = -0.041 ± 0.014, p = 0.004), SES→LIFESTYLE→COGN→DEMENTIA (IE = -0.006 ± 0.001, p < 0.001), SES→COGN→DEMENTIA(IE = -0.040 ± 0.008, p < 0.001), with the last two remaining significant or marginally significant in the uppermost income groups. Diet and social support were among key lifestyle factors involved in socio-economic disparities in dementia incidence. We provide evidence for modifiable risk factors that may delay dementia onset differentially across poverty-income ratio groups, underscoring their importance for future observational and intervention studies.
不同收入群体中痴呆症发病率的种族和社会经济差异及其潜在机制在很大程度上仍不清楚。一项回顾性队列研究通过链接第三次国家健康和营养检查调查（NHANES III）和医疗保险和医疗补助服务中心-医疗保险数据，对所有原因导致的痴呆症发病率在收入群体中进行了研究，随访时间长达≤26 年（1988-2014 年）。在基线时年龄≥60 岁的成年人中构建了 Cox 回归和广义结构方程模型（GSEM）（N=4592）。在年龄和性别调整的 Cox 回归模型中，非西班牙裔黑人（NHB）与白人（NHW）成年人的痴呆症风险更高（HR=1.34，95%CI：1.15-1.55，P<0.001），而在 SES 调整后的模型中，这种关联减弱（HR=1.15，95%CI：1.01-1.34，P=0.092）。SES 与痴呆症风险总体呈负相关（每标准偏差，HR=0.80，95%CI：0.69-0.92，P=0.002，模型 2），主要与中等收入群体相关。在最低和中等收入群体以及 SES 调整模型中，与 NHW 相比，墨西哥裔美国参与者的全因痴呆症风险较低。GSEM 模型进一步检测到 3 条途径，解释了 SES 对痴呆症风险的总影响的>55%（总效应=-0.160±0.067，p=0.022），即 SES→生活方式→痴呆症（间接效应（IE）=-0.041±0.014，p=0.004），SES→生活方式→认知→痴呆症（IE=-0.006±0.001，p<0.001），SES→认知→痴呆症（IE=-0.040±0.008，p<0.001），后两者在最高收入群体中仍然显著或边缘显著。饮食和社会支持是痴呆症发病率存在社会经济差异的关键生活方式因素之一。我们为可能根据贫困收入比群体不同而延迟痴呆症发病的可改变风险因素提供了证据，这突出了它们在未来观察性和干预性研究中的重要性。
