咖啡因及可可鹼之攝取量對高齡者認知功能表現影響之探討-以美國NHANES 2011-2014年資料庫為例

Abstract

背景與目的：人口高齡化已是無可避免的全球趨勢，而隨著年齡的增長，衰老是不可避免的，世界衛生組織（World Health Organization, WHO）提及高齡者常見的病症之一為失智症。認知功能障礙為失智症最早之病程，因此如何預防及延緩，使其避免發展成失智症是我們必須關注的課題。飲食為預防認知功能障礙方式之一，而咖啡因及可可鹼已被證實具有神經保護作用，且兩者的化學結構非常相似，故本研究將兩者一併進行探討，因此本研究旨在瞭解60歲以上高齡者之咖啡因及可可鹼攝取量與認知功能之關聯性。方法：本研究為橫斷性研究，採用美國National Health and Nutrition Examination Survey (NHANES) 資料庫選取2011-2014年60歲以上高齡者之資料，共計2,524位。將其咖啡因及可可鹼攝取量利用四分位數分為四組：各認知功能表現（Consortium to Establish a Registry for Alzheimer’s Disease (CERAD)測驗、動物流暢度測驗、數字符號替換測驗）則利用中位數分為正常及異常二組。使用卡方檢定及邏輯斯迴歸分析，探討高齡者咖啡因及可可鹼攝取量之多寡對於其認知功能是否有所影響。結果：本研究2,524位60歲以上高齡者中，CERAD測驗正常為1,111位，異常為1,413位；動物流暢度測驗正常為1,231位，異常為1,293位；數字符號替換測驗正常為1,221位，異常為1,303位。當中女性、教育程度較高者、已婚／與伴侶同住者、家庭收入與貧困的比例≧1者、有飲酒者及有運動者之認知功能較高，而年齡較大者、高血壓患者、糖尿病患者、憂鬱症患者及吸菸者之認知功能則較低。經調整社會人口學特性與健康狀態變項後，發現攝取咖啡因、可可鹼或同時攝取咖啡因及可可鹼之第四分位數攝取量，對於高齡者各認知功能皆具有保護作用，但當中僅有咖啡因攝取量與CERAD測驗、可可鹼攝取量與數字符號替換測驗、咖啡因及可可鹼攝取量分組與CERAD測驗以及咖啡因及可可鹼攝取量分組與動物流暢度測驗達顯著意義。結論與建議：透過本研究可以發現，攝取較多的咖啡因及可可鹼時，認知功能較高且具有保護作用，且相對於僅有攝取咖啡因或可可鹼時，同時攝取兩者對於預防認知功能障礙具有加成作用。針對實務方面之建議為及早發現及早治療、關注高風險之族群以及在國內外建議攝取量之條件下，適量攝取咖啡因及可可鹼，以降低罹患認知功能障礙之風險；未來研究之建議為可以利用長期追蹤之方式，來瞭解各種攝取物質及情形對於認知功能之因果關係，或是採用臺灣健保資料庫以及國民營養健康調查來進行分析，除檢驗研究結果是否一致外，也能更加瞭解臺灣之現況。Background and objective: The aging of the population is an inevitable global trend, and with increasing age, aging becomes unavoidable. The World Health Organization (WHO) mentions dementia as one of the common conditions in the elderly. Cognitive impairment is the earliest stage of dementia, so understanding how to prevent and delay it to avoid its progression to dementia is a crucial issue.Diet is one of the ways to prevent cognitive impairment, and caffeine and theobromine have been proven to have neuroprotective effects. Since the chemical structures of caffeine and theobromine are very similar, this study aims to explore both substances simultaneously. The objective of this research is to understand the association between the intake of caffeine and theobromine in individuals aged 60 and above and cognitive function.Methods: This study is a cross-sectional research that utilized data from the United States National Health and Nutrition Examination Survey (NHANES) database, selecting information from individuals aged 60 and above for the years 2011-2014, totaling 2,524 participants. The caffeine and theobromine intake levels were categorized into four groups based on quartiles. Cognitive function performance, assessed through the Consortium to Establish a Registry for Alzheimer’s Disease (CERAD) test, Animal Fluency Test, and Digit Symbol Substitution Test, was dichotomized into normal and abnormal groups using the median. By employing chi-square tests and logistic regression analysis, this study aims to investigate whether the quantity of caffeine and theobromine intake among older adults has an impact on their cognitive function.Result: Among the 2,524 elderly people over 60 years old in this study, 1,111 were normal and 1,413 were abnormal in the CERAD test; 1,231 were normal and 1,293 were abnormal in the animal fluency test; 1,221 were normal and 1,303 were abnormal in the digit-symbol replacement test. Among them, women, those with a higher education level, those who are married/living with partners, those with a household income to poverty ratio ≧1, those who drink alcohol and those who exercise have better cognitive function, while those who are older and have high blood pressure Patients with diabetes, depression, and smokers have poorer cognitive function. After adjusting for sociodemographic characteristics and health status variables, it was observed that the fourth quartile intake of caffeine, theobromine, or both, had a protective effect on various cognitive functions in older adults. However, only the intake of caffeine was significantly associated with the CERAD test, the intake of theobromine with the Digit Symbol Substitution Test, and the grouping of caffeine and theobromine intake with the CERAD test and the Animal Fluency Test.Conclusion: Through this study, it can be observed that higher intake of caffeine and theobromine is associated with better cognitive function and has a protective effect. Moreover, simultaneous intake of both substances has an additive effect in preventing cognitive impairment compared to the intake of caffeine or theobromine alone. Practical recommendations include early detection and treatment, attention to high-risk populations, and, adhering to recommended intake levels domestically and internationally, consuming an appropriate amount of caffeine and theobromine to reduce the risk of cognitive impairment. Suggestions for future research involve utilizing long-term tracking to understand the causal relationship between various substances and cognitive function. Alternatively, using Taiwan's National Health Insurance database and the National Nutrition and Health Survey for analysis could provide insights into the consistency of research results and a deeper understanding of the situation in Taiwan.