Dementia Alzheimers

Gut problems, such as constipation, can have an important impact on quality of life of people who have them, and have been associated with higher risk of developing neurological diseases such as Parkinson's or Alzheimer's disease. Recent studies suggest that gut problems may also have implications for the progression of these diseases, as constipation is a risk factor for faster Parkinson's and Alzheimer's progression. However, how constipation and brain diseases are linked is unknown. Previous research has suggested that gut changes may lead to inflammation, which could play a role in accelerating the progression of both movement and memory problems in Parkinson's and memory and thinking problems in people with cognitive impairment. Methane is a gas that is naturally produced by microorganisms in the gut. Levels of methane can be measured using a simple breath test. Higher methane levels in the breath are thought to be more common in people with Parkinson's disease (PwP) when compared to people without Parkinson's (healthy controls) and have been associated with gut symptoms, particularly constipation, as well as worse movement problems in PwP, although they are less understood in conditions that affect memory and thinking (like dementia or mild cognitive impairment). The investigators want to better understand the changes in the gut of PwP and people with cognitive impairment (e.g. mild cognitive impairment or dementia). They will compare breath methane levels in PwP, people with cognitive impairment, people with REM Sleep Behaviour Disorder (a sleep condition linked to a higher risk of developing Parkinson's) and healthy participants. Participants will be followed-up over time to assess how methane levels are linked to changes in the blood and the stools, gut function, and clinical symptoms. This study has 2 components: Component 1: observational study, where the study investigators will follow 200 participants over 2 visits, 18 months apart. The study will recruit 4 groups of people: 50 people with Parkinson's disease, 50 people at high risk of developing Parkinson's disease (people with REM Sleep behaviour disorder), 50 people with other conditions affecting cognition (e.g. dementia, mild cognitive impairment), and 50 healthy controls. Component 2: study with 15 people with Parkinson's, who produce high methane levels, to test whether a probiotic (Lactobacillus reuteri) affects how much methane is produced.

This project's main goal is to use state-of-the-art passive sensing techniques to identify digital biomarkers that relate to bioenergetic changes in the brain due to nicotinamide riboside supplementation in those with mild cognitive impairment and mild Alzheimer's dementia.

This study will investigate the validity of the HOGAR EEG/PSG monitoring kit designed by Bitbrain as a tool for characterizing and assessing cognitive function in older adults, as well as for detecting and predicting cognitive decline. The kit consists of two EEG headbands and a mobile computing device that allows measurements of sleep patterns (PSG) and brain activity (EEG) in a home environment.

The goal of this observational cross-sectional study is to explore the characteristics of language, speech, and motor function in persons with Mild Cognitive Impairment due to Alzheimer's disease ("MCI due to AD") and persons with mild and moderate Alzheimer's disease ("AD"). This study aims to: * Explore motor, speech, and language functions in MCI due to AD and mild and moderate AD. * Combine the characteristics of motor, language, and speech functions to gain more insight into the association of language, speech, and motor changes during MCI due to AD and mild and moderate AD. Researchers will compare the outcomes to an age-matched control group without cognitive impairment. Participants will undergo: * Two motor function tests to assess gait and hand grip strength. * Four language and speech function tests to assess spontaneous speech and verbal fluency..

Alzheimer's disease (AD) may currently be diagnosed using molecular biomarkers in cerebrospinal fluid (CSF) and/or positron emission tomography (PET). These diagnostic procedures are highly accurate, but the high cost and low availability hamper their feasibility. Recently, ultrasensitive blood tests predicting Alzheimer pathologies in the brain have been developed. These tests have a reliable ability to differentiate AD from other neurodegenerative disorders and identify AD across the clinical continuum with high sensitivity and specificity in research cohorts with a high prevalence of AD. This project will assess the predictive value of these tests in a general practice population. The hypothesis is that the actual blood panel will have high positive predictive value for a diagnosis of Alzheimer's disease in the primary health care setting.

The researchers plain to build a large-scale, longitudinal, prospective cohort characterized by TCM dampness syndrome. With the biobank of this cohort the investigators want to find the causality between TCM dampness syndrome and clinical chronic diseases and a new way to treat clinical disease.

The PUMCH Dementia Cohort is a hospital-based, observational study of Chinese elderly with cognitive impairment.