Health behaviors over the adult lifecourse and cognitive aging

描述（由申请人提供）：越来越多的证据表明健康行为与认知老化之间存在关联。吸烟、饮酒、体育活动和营养都被发现与认知功能低下和痴呆症有关。健康行为在多大程度上可以解释认知老化轨迹具有重大的公共卫生相关性，特别是因为它们可能是痴呆症的关键可改变风险因素。这项建议的首要目标是研究健康行为对成年人生命过程的综合影响，以确定从中年开始的认知老化轨迹。具体目标是：1.研究吸烟、饮酒、体育活动和饮食对认知能力下降的综合影响，以评估中年早期、中期和晚期健康行为的影响是否最重要，以及这种影响是否会随着时间的推移而积累。2.研究一种行为的改变在多大程度上导致了其他行为的改变，以及这些改变在多大程度上影响了认知老化。3.研究健康行为和中年开始的认知老化之间的双向关联：4。研究生物学变化（如血管危险因素和疾病）在多大程度上解释了健康行为和认知老化之间的关联。我们还将研究健康行为和认知老化之间的关联的两个潜在效应修饰符所起的作用：社会经济地位（SES）和载脂蛋白E（APOE）e4等位基因。 此外，我们的工作将集中在做健康行为的测量问题：将详细关注健康行为的分类，以了解每个行为和认知老化之间的关联的形状，不同的措施饮食是否与认知老化有类似的关联，以及身体活动的客观和主观措施之间是否存在差异。我们还将研究健康行为对认知老化特定领域的影响，其中记忆和执行功能是两个主要方面。 白厅II测试组合在第5阶段被引入到整个白厅II队列中，当时参与者平均年龄为55岁，并且已经在过去10年中进行了行为评估。目前正在收集第三波认知数据，并将于2009年底提供，使我们能够看到认知变化的轨迹。虽然该提案主要基于英国白厅，但研究团队由法国和英国的科学家组成，为我们提供了验证法国GAZEL研究数据的一些结果的机会。 公共卫生相关性：预期寿命的持续增长与痴呆症的患病率随年龄增长而上升的知识同步，60岁后每4-5年翻一番。到80岁时，三分之一以上的人口可能患有痴呆症;对工业化国家来说，这在提供护理方面是一个前所未有的挑战。虽然痴呆症通常发生在生命的晚期，但人们越来越认识到，有一个很长的临床前阶段，使在此阶段之前和期间对风险因素的评估成为预防或延迟痴呆症发作的关键下一步。在这种“长期”观点的驱动下，我们的研究集中在从中年早期开始的认知老化异质性的决定因素上。现有的研究表明，健康行为与认知老化之间存在关联;吸烟、饮酒、体育活动和营养都被发现与认知功能低下和痴呆症有关。目前尚不清楚的是，这些行为在多大程度上决定了认知老化的轨迹。在公共卫生领域，为什么这些知识如此重要？因为这些行为很可能是痴呆症的关键危险因素，这些因素既可以改变，也可以在国家一级进行低成本干预。在研究方面，这一建议的独特之处是使用综合测试组合对认知功能进行三次重复评估，第一次评估在中年早期进行，可以检查认知功能变化的拐点。

DESCRIPTION (provided by applicant): There is increasing evidence of an association between health behaviors and cognitive aging. Smoking, alcohol, physical activity and nutrition have all been found to be associated with poor cognitive function and dementia. The extent to which health behaviors can explain cognitive aging trajectories is of substantial public health relevance, particularly as they may be 'the' key modifiable risk factors for dementia. The overarching aim of this proposal is to examine the combined impact of health behaviors over the adult lifecourse in determining cognitive aging trajectories starting from midlife. The specific aims are: 1. To examine the combined impact of smoking, alcohol consumption, physical activity and diet on cognitive decline in order to assess whether the impact of health behaviors in early, mid and late midlife is most important and whether this effect accumulates over time. 2. To examine the extent to which change in one behavior leads to changes in others and the extent to which these changes influence cognitive aging. 3. To examine bidirectional associations between health behaviors and cognitive aging starting in midlife: 4. To examine the extent to which biological changes, such as those in vascular risk factors and diseases, explain the association between health behaviors and cognitive aging. We will also examine the role played by two potential effect modifiers of the association between health behaviors and cognitive aging: socioeconomic status (SES) and the apolipoprotein E (APOE) e4 allele. In addition, our work will focus on issues to do measurement of health behaviors: Detailed attention will be paid to the categorization of the health behaviors in order to understand the shape of the association between each measure of behavior and cognitive aging, whether different measures diet have similar associations with cognitive aging and whether there are discrepancies between the objective and subjective measures of physical activity. We will also examine the impact of health behaviors on specific domains of cognitive aging, with memory and executive function as two major aspects. The Whitehall II test battery was introduced to the full Whitehall II cohort at phase 5 when participants were on average 55 years old and had already been assessed for behaviors over the previous 10 years. A third wave of cognitive data is currently being collected, and will be available late 2009, allowing us look at trajectories of cognitive change. Although the proposal is based primarily on the British Whitehall, the research team is composed of scientists based in France as well as the UK, providing us with the opportunity to validate some of our results in data from the French GAZEL study. PUBLIC HEALTH RELEVANCE: Continuing increases in life expectancy come in tandem with knowledge that the prevalence of dementia rises with age, doubling every 4-5 years after the age of 60. By age 80 over one third of the population is likely to be living with dementia; for industrialized countries an unprecedented challenge in terms of care provision. Although dementia generally occurs late in life, it is increasingly recognized that there is a long preclinical phase, making the evaluation of risk factors prior to and during this phase a crucial next step in the battle to prevent or delay the onset of dementia. Driven by this "long" view of dementia our research focuses on the determinants of heterogeneity in cognitive aging starting from early midlife. Existing research suggests an association between health behaviors and cognitive aging; smoking, alcohol, physical activity and nutrition have all been found to be associated with poor cognitive function and dementia. What remains unknown is the extent to which these behaviors, acting in combination, determine cognitive aging trajectories. In public health terms, why is this knowledge so important? Because these behaviors are likely to be 'the' key risk factors for dementia that are both modifiable and amenable to low-cost intervention at the national level. In research terms, the unique feature of this proposal is three repeat assessments of cognitive function using a comprehensive test battery with a first assessment carried out in early midlife allowing an examination of the inflection point in changes in cognitive functioning.