Department of Epidemiology, School of Public Health, University of Pittsburgh, 130 North Bellefield Avenue, Room 354, Pittsburgh, PA, 15261, USA.
Eur J Epidemiol. 2022 Feb;37(2):129-131. doi: 10.1007/s10654-022-00849-6. Epub 2022 Feb 25.
The increasing longevity of the population has resulted in dementia becoming a leading cause of both death and disability. Dementia is not a single disease. Studies of rare Mendelian disorders have documented that Alzheimer's disease, the most common cause of dementia, is associated with a long incubation period from amyloid deposition to neurodegeneration to mild cognitive impairment and dementia. There are three broad hypotheses related to the causes of Alzheimer's dementia: (1) an aging process; (2) brain vascular disease; and (3) metabolic abnormalities associated with either increased production of amyloid-β or decreased clearance from the brain. Therefore, research on the early stages of the dementia process are of high priority. This paper reports that higher energy intake in both the Nurses' Health Study and Health Professionals Follow-up Study is associated with very early symptoms that lead to mild cognitive impairment and dementia. The results are very interesting but hard to interpret because they also show that higher energy intake is not related to body mass index, a very unusual observation. A likely hypothesis is that there is an association between reporting of dietary intake and subjective symptoms, i.e. reporting bias, accounting for their results.
人口寿命的延长导致痴呆症成为死亡和残疾的主要原因。痴呆症不是一种单一的疾病。对罕见的孟德尔疾病的研究记录表明，阿尔茨海默病是痴呆症最常见的病因，从淀粉样蛋白沉积到神经退行性变、轻度认知障碍到痴呆症，存在一个很长的潜伏期。与阿尔茨海默病性痴呆症相关的原因有三个广泛的假说：（1）衰老过程；（2）脑血管疾病；（3）与脑内淀粉样β的产生增加或清除减少相关的代谢异常。因此，对痴呆症过程早期阶段的研究具有很高的优先级。本文报告称，护士健康研究和健康专业人员随访研究中的能量摄入较高与导致轻度认知障碍和痴呆症的早期症状有关。这些结果非常有趣，但难以解释，因为它们还表明，能量摄入较高与体重指数无关，这是一个非常不寻常的观察结果。一个可能的假设是，饮食摄入和主观症状之间存在关联，即报告偏倚，这解释了它们的结果。
