Alzheimer’s Disease (AD): Risks, Treatments, Prevention, and Future Implementations

Alzheimer’s disease (AD) is the most common type of dementia found among geriatric populations worldwide and is growing quickly in low- and middle-income countries. Alzheimer’s disease affects approximately 36.6 million people, and that number is expected to double over the next two decades. Those most susceptible to Alzheimer’s are over the age of 60, though other associated factors such as sex, poor nutrition, education, impaired functional status, body mass index, diabetes, depression, smoking, alcohol, fish intake, and pesticide exposure have been reported, though none are clear. Gaining a better understanding of the etiology of AD requires multiple-site-targeted therapy to control the disease at the initial level. On the other hand, evidence suggests that risk factors for AD are modifiable. Hence reduction in associated risk factors may require very long follow-ups to make people aware of their effect on AD incidence. If these factors are effective in preventing the progression of AD, the target populations could be affected at the early stages of AD or even patients with more advanced disease.

Gut microbiota-astrocyte axis: new insights into age-related cognitive decline

With the rapidly aging human population,age-related cognitive decline and dementia are becoming increasingly prevalent worldwide.Aging is considered the main risk factor for cognitive decline and acts through alterations in the composition of the gut microbiota,microbial metabolites,and the functions of astrocytes.The microbiota–gut–brain axis has been the focus of multiple studies and is closely associated with cognitive function.This article provides a comprehensive review of the specific changes that occur in the composition of the gut microbiota and microbial metabolites in older individuals and discusses how the aging of astrocytes and reactive astrocytosis are closely related to age-related cognitive decline and neurodegenerative diseases.This article also summarizes the gut microbiota components that affect astrocyte function,mainly through the vagus nerve,immune responses,circadian rhythms,and microbial metabolites.Finally,this article summarizes the mechanism by which the gut microbiota–astrocyte axis plays a role in Alzheimer’s and Parkinson’s diseases.Our findings have revealed the critical role of the microbiota–astrocyte axis in age-related cognitive decline,aiding in a deeper understanding of potential gut microbiome-based adjuvant therapy strategies for this condition.

Comorbidity Burden of Dementia:A Hospital-Based Retrospective Study from 2003 to 2012 in Seven Cities in China

Dementia is increasing dramatically and imposes a huge burden on society. To date, there is a lack of data on the health status of patients with dementia in China. In an attempt to investigate the comorbidity burden of dementia patients in China at the national level, we enrolled 2,938 patients with Alzheimer＇s disease（AD）, vascular dementia（Va D）, or other types of dementia, who were admitted to tertiary hospitals in seven regions of China from January2003 to December 2012. The Charlson Comorbidity Index（CCI） was used to evaluate the comorbidity burden of the patients with dementia. Among these patients, 53.4% had AD, 26.3% had Va D, and 20.3% had other types of dementia. The CCI was 3.0 ± 1.9 for all patients,3.4 ± 1.8 for those with Va D, and 3.0 ± 2.1 for those with AD. The CCI increased with age in all patients, andthe length of hospital stay and daily expenses rose with age and CCI. Males had a higher CCI and a longer stay than females. Moreover, patients admitted in the last 5 years of the study had a higher CCI than those admitted in the first 5 years. We found that the comorbidity burden of patients with dementia is heavy. These findings provide a better understanding of the overall health status of dementia patients, and help to increase the awareness of clinicians and policy-makers to improve medical care for patients.

北京市城乡痴呆及其主要亚型的患病率

目的 研究北京市城乡居民老年期痴呆及其主要亚型的患病率和流行特征。方法 通过分层多级整群抽样 ,以北京市 12个城市居委会和 17个村委会全部 5 913名 5 5岁和以上的居民为样本 ,分期入户调查。实查 5 74 3名 ,受访率 96 1%。第一期于 1997年应用简易智能状态检查(MMSE)进行筛查。第二期对筛查阳性和部分阴性者进行成套的诊断性检查 ,按国际标准诊断痴呆、可能或很可能的阿尔茨海默痴呆 (AD)和血管性痴呆 (VaD)。第三期始于 1998年 ,随访进入第二期调查的全部对象 ,进一步评估诊断。结果 痴呆患病率及年龄标化患病率 5 5岁及以上者分别为 4 6%和 4 2 % ,AD两率分别为 2 2 %和 2 0 % ,VaD则分别为 1 6%和 1 5 %。AD比VaD发病年龄晚 ,病程长 ,病死率低。AD和VaD的年龄别患病率均随年龄而升高 ,AD每 5岁增高约 1倍 ,VaD则缓慢上升。AD年龄标化患病率 5 5岁及以上女性高于男性 ,分别为 1 7%和 2 1% ;VaD则男性高于女性 ,分别为1 7%和 1 3 %。AD年龄标化患病率的城乡差异不明显 ( 1 8%∶2 2 % ) ,VaD农村高于城市 ( 2 2 %∶1 0 % )。无论AD或VaD ,与受教育程度的关系均未显示规律性变化。结论 本次调查的北京市城乡居民老年期痴呆及主要亚型的患病率高于既往调查的估计 。

成都地区老年期痴呆患病率调查

目的 调查成都地区城乡老年期痴呆和阿尔茨海默病 (AD)的患病率。方法 采用分层随机整群抽样方法 ,将成都市 1 9个区市县 (总人口 972万 )分为城区、郊区、近郊和远郊 ,根据各层人口占总人口比例确定各层应查≥ 55岁的老人数 ( 5555人 ) ,实查 53 53人。调查采用筛查和确诊两阶段法 ,按美国精神障碍诊断与统计手册第 3版修订本的标准诊断痴呆。结果 ( 1 )查出痴呆患者1 43例 ,患病率为 2 67%。其中AD为 2 0 5% ,血管性痴呆 (VD)为 0 3 7% ,其他痴呆为 0 2 4 %。 ( 2 )女性患病率 ( 3 1 4% )高于男性 ( 2 1 6% ;P <0 0 5)。 ( 3 )痴呆患者的平均年龄 [男 ( 80± 9)岁 ,女 ( 82± 7)岁 ]高于正常老年人 [男女均为 ( 67± 8)岁 ;P <0 0 0 1 ] ,且痴呆患病率随年龄增长而上升。 ( 4)农业人口的患病率 ( 2 79% )高于非农业人口 ( 2 4 0 % ) ,但差异无显著性。 ( 5)文盲老人的患病率 ( 4 4 5% )较小学 ( 1 4 8% )和初中及其以上 ( 0 1 7% )文化程度者高 (P <0 0 0 1 )。结论 AD是成都地区老人中主要的痴呆类型 ,VD次之。文盲老人的痴呆患病率高 ,老年期痴呆患病率随年龄的增长而升高。

中国60岁及以上人群老年期痴呆患病率Meta分析

目的 探讨2000-2015年中国≥60岁人群老年期痴呆患病率情况。方法 通过系统检索中国知网数据库、万方数据库、维普中文科技期刊数据库和PubMed等中英文数据库中有关老年期痴呆患病率的研究文献，检索时间为2000-2015年。采用R软件进行Meta分析。结果 共纳入25篇文献，总调查人数为76 980人，其中患者4 295例；经Meta分析，老年期痴呆患病率为5.15%（95%CI：4.21%-6.09%）；亚组分析显示，老年期痴呆患病率女性（6.08%）高于男性（4.10%），年龄越大者患病率越高（60-64岁至≥85岁年龄人群老年期痴呆患病率从1.01%升至23.60%），阿尔茨海默病患病率（3.56%）高于脑血管性痴呆患病率（1.11%），文盲人群患病率（8.74%）高于非文盲人群（3.17%），非在婚人群患病率（6.83%）高于在婚人群（3.95%）。结论 中国≥60岁人群老年期痴呆患病率较高，年龄、性别、文化水平和婚姻状况可能影响老年期痴呆的发生。