Western Diet as an Independent Predictor of Asthma Prevalence and Morbidity

描述(申请人提供)：哮喘是一种常见的呼吸系统疾病，在美国日益流行。发病率和死亡率是极端的，哮喘的患病率在贫困的少数群体中高得不成比例。哮喘患病率总体上呈上升趋势，同时向西方饮食模式过渡，其典型特征是加工食品(如肉类和精制谷物)、n6-多不饱和脂肪酸(PUFAs)、高脂肪乳制品以及含糖甜点和饮料的摄入量增加。到目前为止，大多数饮食和哮喘研究都集中在个别维生素、矿物质和脂肪酸上。结果各不相同，补充试验显示结果喜忧参半或呈阴性。考虑到人类饮食的复杂性和成分之间的相互作用，人们越来越感兴趣的概念是，哮喘患者的营养物质可能在食物和饮食模式中协同作用，而不是孤立地发挥作用。新出现的证据表明，富含水果、蔬菜、全谷物、n3-多不饱和脂肪酸和抗氧化剂摄入量的饮食可能是一种“呼吸健康”的饮食，但还需要进行验证性研究。一个令人反感的问题是，是否存在加重哮喘的不良饮食。提出的假说：如上所述，西方饮食模式将与美国成年人哮喘发病率的增加显著和独立相关。哮喘和西方饮食模式之间的独立联系将在两个不同的队列中进行评估：(1)社区动脉粥样硬化风险(ARIC)，这是一个由来自全美四个社区的参与者组成的大型队列，以及(2)作为吸入性研究的一部分，主要是贫穷的非裔美国人巴尔的摩市市中心的队列，这是一个正在接受全面环境和人口特征表征的成年哮喘患者队列。提出了两个新的目标。(1)在一项大规模、前瞻性的美国流行病学队列研究中，调查西方饮食模式与哮喘患病率和发病率之间的关系。与ARIC调查人员的合作将被用来确定西方饮食模式对ARIC中哮喘患病率、症状、药物使用和住院的影响；否则，本队列中未涉及的问题将被用于确定西方饮食模式在队列中定义的“西方”和“谨慎”饮食模式。(2)在吸入性研究中，对70名城市成人哮喘患者(主要是非裔美国人)，调查西方饮食模式与哮喘发病率之间的关系。巴尔的摩特有的定量食物频率问卷，24小时饮食召回，以及详细的人体测量措施(将饮食的影响与肥胖的影响分开)，将被添加到父协议中。个人饮食模式将与哮喘有关 症状、住院和用药情况，同时控制潜在的协变量。这种双人群方法将使我们能够确定饮食对哮喘患病率和发病率的显著影响，饮食是一个潜在的可改变的危险因素，在美国的大队列和较小的高危个体队列中都是如此。研究结果将告诉我们，需要采取饮食干预措施，以改善哮喘的健康结果。

DESCRIPTION (provided by applicant): Asthma is a common respiratory disease of increasing prevalence in the Unites States. Morbidity and mortality rates are extreme, and the prevalence of asthma is disproportionately high in poor, minority populations. Rising asthma prevalence overall has trended in parallel to transition to a Western diet pattern, typified by higher intakes of processes foods (e.g. meats and refined grains), n6-polyunsaturated fatty acids (PUFAs), high fat dairy products, and sugary desserts and drinks. Most diet and asthma research to date has focused on individual vitamins, minerals, and fatty acids. Results vary, and supplement trials have demonstrated mixed or negative results. Given the complex nature of human diet with interaction between components, there is increased interest in the concept that nutrients in asthmatics may act synergistically in foods and diet patterns, rather than in isolatio. Emerging evidence suggests that a diet high in fruit, vegetable, whole grain, n3-PUFAs, and antioxidant intake may be a "respiratory healthy" diet but confirmatory studies are needed. A countering question is whether there exists an unfavorable diet that worsens asthma. Proposed hypothesis: A Western dietary pattern, as defined above, will be significantly and independently associated with increased asthma morbidity in US adults. Independent links between asthma and a Western dietary pattern will be evaluated in two distinct cohorts: (1) the Atherosclerosis Risk in Communities (ARIC) a large cohort with participants from four communities across the US, and (2) a primarily poor, African-American, inner city Baltimore City cohort prospectively evaluated as part of the INHALE Study, a cohort of adult asthmatics undergoing comprehensive environmental and demographic characterization. Two novel aims are proposed. (1) To investigate the association between Western dietary pattern and asthma prevalence and morbidity in a large, prospective, US epidemiologic cohort study. A collaborative effort with ARIC investigators who have previously defined "Western" and "prudent" dietary patterns in the cohort will be employed to determine effects of Western diet pattern on asthma prevalence, symptoms, medications use, and hospitalizations in ARIC; questions otherwise unaddressed in this cohort. (2) To investigate the association between Western dietary pattern and asthma morbidity among a cohort of 70 urban, primarily African-American asthmatic adults in the INHALE Study. A Baltimore-specific quantitative food frequency questionnaire, 24-hour dietary recalls, and detailed anthropometric measures (to isolate the effects of diet from those of obesity), will be added to the parent protocol. Individual dietary pattern will be linked to asthma symptoms, hospitalizations, and medication use while controlling for potential covariates. This two-population approach will allow us to identify significant effects of diet, a potentially modifiable risk factor, on asthma prevalence and morbidity in both a large, US cohort and a smaller cohort of high-risk individuals. Study results will inform the need for dietary interventios aimed at improving asthma health outcomes.