JAMA：阿兹海默病风险的影响因素
芝加哥 - 据8月12日刊JAMA上的一则研究披露，对那些饮食中富含水果、蔬菜、豆类、谷类和鱼但红肉和禽肉量较少且身体多运动的老年人来说，他们罹患阿兹海默病的相关风险较低。有关身体活动对阿兹海默病（AD）或痴呆症的影响的研究就像是饮食习惯对AD的影响一样显示了混合性的结果。根据文章的背景资料，身体运动与饮食结合起来会对AD有什么相关影响尚未被人们研究过。
Columbia University Medical Center, New York的Nikolaos Scarmeas, M.D.及其同僚对身体活动与AD风险之间的关系以及身体活动与坚持摄取地中海地区饮食对AD风险的影响进行了检验。这一研究包括了2组人，他们是纽约市的1880位居住在社区中的老年人，这些人在研究开始的时候没有痴呆症。这些人都可获取有关饮食和身体运动的有关资讯。这些人在1992年到2006年期间，每隔大约1.5年就会接受标准化的神经内科和神经心理学的检测。
这些受试者所接受的检测有：他们对摄取地中海地区饮食的坚持程度（标尺0-9，被分成低、中或高坚持度）以及他们身体的活动度（即每周参加不同身体运动的总和，用身体活动类型 [ 轻度、中度、激烈] 进行加权；他们被归分为：无身体运动、有一些身体运动或很多身体运动 [分为低或高度]）；对他们的分类还分有单独性的及综合性的。饮食上的较高分数可通过进食较多的水果、蔬菜、豆类、谷类和鱼，进食较少的肉类和奶制品；以及单价不饱和脂肪相对饱和性脂肪的较高比例以及轻度至中度的饮酒量来获取。
这些人的追踪时间平均为5.4年，在此期间，共有282人发生了AD。
当被同时观察的时候，身体运动及坚持地中海地区样的饮食都与AD的发病率之间存在显著的相关性。根据研究人员披露：“那些属于中间三分位数饮食坚持度的人，其与AD风险下降2-14%具有关联性；那些属于最高三分位数饮食坚持度的人，其与AD风险下降32-40%具有关联性。与身体不运动的人相比也有类似的结果，即那些报告说有一些身体运动的人，其AD风险减少了33-48%。”
“总之，我们的结果对身体运动和饮食习惯与AD风险之间存在潜在的独立关系并起着重要的作用这种说法是支持的。”
JAMA. 2009;302:627-637.
Physical Activity, Diet, and Risk of Alzheimer Disease
CONTEXT: Both higher adherence to a Mediterranean-type diet and more physical activity have been independently associated with lower Alzheimer disease (AD) risk but their combined association has not been investigated.
OBJECTIVE: To investigate the combined association of diet and physical activity with AD risk. DESIGN, SETTING, AND PATIENTS: Prospective cohort study of 2 cohorts comprising 1880 community-dwelling elders without dementia living in New York, New York, with both diet and physical activity information available. Standardized neurological and neuropsychological measures were administered approximately every 1.5 years from 1992 through 2006. Adherence to a Mediterranean-type diet (scale of 0-9; trichotomized into low, middle, or high; and dichotomized into low or high) and physical activity (sum of weekly participation in various physical activities, weighted by the type of physical activity [light, moderate, vigorous]; trichotomized into no physical activity, some, or much; and dichotomized into low or high), separately and combined, were the main predictors in Cox models. Models were adjusted for cohort, age, sex, ethnicity, education, apolipoprotein E genotype, caloric intake, body mass index, smoking status, depression, leisure activities, a comorbidity index, and baseline Clinical Dementia Rating score.
MAIN OUTCOME MEASURE: Time to incident AD. RESULTS: A total of 282 incident AD cases occurred during a mean (SD) of 5.4 (3.3) years of follow-up. When considered simultaneously, both Mediterranean-type diet adherence (compared with low diet score, hazard ratio [HR] for middle diet score was 0.98 [95% confidence interval {CI}, 0.72-1.33]; the HR for high diet score was 0.60 [95% CI, 0.42-0.87]; P = .008 for trend) and physical activity (compared with no physical activity, the HR for some physical activity was 0.75 [95% CI, 0.54-1.04]; the HR for much physical activity was 0.67 [95% CI, 0.47-0.95]; P = .03 for trend) were associated with lower AD risk. Compared with individuals neither adhering to the diet nor participating in physical activity (low diet score and no physical activity; absolute AD risk of 19%), those both adhering to the diet and participating in physical activity (high diet score and high physical activity) had a lower risk of AD (absolute risk, 12%; HR, 0.65 [95% CI, 0.44-0.96]; P = .03 for trend).
CONCLUSION: In this study, both higher Mediterranean-type diet adherence and higher physical activity were independently associated with reduced risk for AD.
