The effects of study design characteristics on dementia assessment: Recommendations for future epidemiologic studies

项目总结 意义：阿尔茨海默病和相关痴呆症(ADRD)是一项重大的公共卫生挑战。 ADRD的流行病学研究依赖于通过认知测试和调查诊断痴呆症 关于日常活动中的功能限制(即洗澡困难)的问题。然而，存在着广泛的变异性 实施考核。在237份关于ADRD流行率和发病率的科学出版物中， 研究人员使用了230种不同的测量方法。方法在具体的测试，问题， 以及使用的算法方法。这种异质性带来了挑战，很可能是观察到的 对患病率和糖尿病等可改变的风险因素的影响的估计不一致， 这一风险将随着暴露流行率的预期增加而变得更加重要。的首要目标是 这项研究旨在制定指导方针，以改进未来流行病学研究中的痴呆症测量。 具体目标：我们的目标是表征研究设计特征对两者之间的关联的影响 ADRD和关于认知和功能障碍的个人调查问题。具体来说，在目标1中，我们将 评估地理环境如何影响跨国痴呆症研究中的测量。在目标2中，我们将 在侧重于确定痴呆的横断面研究中评估痴呆测量之间的差异 流行的痴呆症和纵向研究的重点是确定偶发痴呆症。这两个目标都将： (1)描述在调查中管理的特定问题与以下任一项之间的联系的差异 认知功能或痴呆症，以及(2)量化测量改进对 糖尿病(ADRD的既定危险因素)与认知功能或痴呆之间的关系。 方法：对于目标1，我们将使用协调认知评估协议(HCAP)调查的数据 在美国、墨西哥、英国、南非和印度。我们将比较两者之间的关联 每个调查问题都有认知功能，使用验证性因素分析和Logistic回归。 我们还将使用Logistic回归来评估糖尿病与传统和改进之间的联系。 认知功能的短期测量。目标2将利用来自宗教教团的丰富的纵向数据 研究-记忆和衰老项目(ROSMAP)研究。首先，我们将使用Logistic回归模型 评估每个调查问题之间的关联差异的通用估计方程 普遍的痴呆症与偶发痴呆症。第二，我们将评估改善痴呆症的影响 用于糖尿病和痴呆症风险之间关联的纵向事件间隔时间模型的算法。 奖学金培训：艾玛·尼科尔斯是约翰斯医院流行病学系的博士生 霍普金斯大学彭博公共卫生学院。通过有指导的研究、课程和专业技能 在发展方面，拟议的培训计划将使Nichols女士具备所需的工具和技能，以便 一位在认知老化和痴呆症流行病学方面具有创新性的独立研究人员。

PROJECT SUMMARY Significance: Alzheimer’s disease and related dementias (ADRD) are a major public health challenge. Epidemiologic research on ADRD relies on the diagnosis of dementia via cognitive testing and survey questions on functional limitations in daily activities (i.e difficulty bathing). However, there is wide variability in the implementation of assessments. Across 237 scientific publications on ADRD prevalence and incidence, researchers used 230 different measurement methods. Methods varied widely in the specific tests, questions, and algorithmic approaches used. This heterogeneity poses challenges, and is likely responsible for observed inconsistencies in the estimation of both prevalence and the effects of modifiable risk factors such as diabetes, a risk that will grow in importance with anticipated increases in exposure prevalence. The overarching goal of this research is to develop guidelines to improve dementia measurement in future epidemiologic studies. Specific Aims: We aim to characterize the effect of study design characteristics on the association between ADRD and individual survey questions on cognition and functional impairment. Specifically, in Aim 1, we will assess how geographic setting affects measurement in cross-national dementia research. In Aim 2, we will assess differences between dementia measurement in cross-sectional studies focused on the ascertainment of prevalent dementia and longitudinal studies focused on the ascertainment of incident dementia. Both Aims will: (1) characterize variations in the associations between specific questions administered on surveys and either cognitive functioning or dementia, and (2) quantify the impact of improvements in measurement on the association between diabetes (an established risk factor for ADRD) and cognitive functioning or dementia. Approach: For Aim 1 we will use data from the Harmonized Cognitive Assessment Protocol (HCAP) surveys in the United States, Mexico, England, South Africa, and India. We will compare the associations between each survey question with cognitive functioning, using both confirmatory factor analysis and logistic regression. We will also use logistic regression to evaluate the association between diabetes and traditional vs. improved short measures of cognitive functioning. Aim 2 will leverage rich longitudinal data from the Religious Orders Study-Memory and Aging Project (ROSMAP) studies. First, we will use logistic regression models with generalized estimating equations to assess differences in the associations between each survey question and prevalent versus incident dementia. Second, we will assess the impact of improvements to dementia algorithms for use in longitudinal time-to-event models for the association between diabetes and dementia risk. Fellowship Training: Emma Nichols is a PhD student in the Department of Epidemiology at the Johns Hopkins Bloomberg School of Public Health. Through mentored research, coursework, and professional skills development, the proposed training plan will equip Ms. Nichols with the tools and skillset required to become an innovative, independent researcher in the epidemiology of cognitive aging and dementia.