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，健康行为和认知老化之间存在联系。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。健康行为解释认知老化轨迹的程度与公共卫生密切相关，特别是因为它们可能是痴呆症的关键可改变的风险因素。这项建议的主要目的是检查健康行为在确定从中年开始的认知老化轨迹中对成人生命过程的综合影响。具体目标是：1.研究吸烟、饮酒、体育锻炼和饮食对认知能力下降的综合影响，以评估中年早期、中期和后期的健康行为是否最重要，以及这种影响是否会随着时间的推移而积累。2.研究一种行为的变化在多大程度上导致其他行为的变化，以及这些变化对认知老化的影响程度。3.考察从中年开始的健康行为和认知老化之间的双向联系：4.考察生物学变化，如血管风险因素和疾病的变化，在多大程度上解释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联系的两个潜在效应修饰物所起的作用：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健康行为测量的问题上：详细关注健康行为的分类，以了解每种行为测量与认知老化之间的关联形式，不同测量饮食是否与认知老化有类似的关联，以及体力活动的客观测量和主观测量之间是否存在差异。我们还将考察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测试电池是在第5阶段引入整个白厅II队列的，当时参与者的平均年龄为55岁，并且已经接受了过去10年的行为评估。第三波认知数据目前正在收集中，将于2009年底提供，使我们能够看到认知变化的轨迹。尽管该建议主要基于英国白厅，但研究团队由法国和英国的科学家组成，这为我们提供了在法国GAZEL研究的数据中验证我们的一些结果的机会。 与公共卫生相关：预期寿命的持续增长伴随着痴呆症患病率随着年龄的增长而上升，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，在提供护理方面是前所未有的挑战。尽管痴呆症通常发生在晚年，但人们越来越认识到，有一个漫长的临床前阶段，这使得在这一阶段之前和期间对风险因素的评估成为预防或推迟痴呆症发病的关键下一步。在痴呆症这种“长期”观点的推动下，我们的研究重点放在从中年早期开始的认知老化的异质性决定因素上。现有研究表明，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共同决定了认知老化的轨迹。从公共卫生的角度来看，为什么这一知识如此重要？因为这些行为很可能是痴呆症的关键风险因素，既可以改变，也可以接受国家层面的低成本干预。在研究方面，这项建议的独特之处在于，使用综合测试组合对认知功能进行了三次重复评估，第一次评估在中年早期进行，允许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.