Healthy Aging
Conditions
Brief summary
The purpose of this study is to assess the link between sleep and the clearance of waste products from the brain. This will be assessed in a group of healthy older adults.
Detailed description
First, the investigators want to assess the relationship between sleep parameters and markers for brain clearance, assessed with MRI and blood samples. Second, the investigators want to probe whether associations can be influenced by modulation of sleep parameters by means of auditory stimulation.
Interventions
BEHAVIORALAuditory Stimulation
enhancement of sleep slow wave activity through acoustic stimulation
BEHAVIORALSham (no stimulation)
Playing no tones during sleep but still recording brain activity
Sponsors
University of Zurich
University Children's Hospital, Zurich
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
DOUBLE (Subject, Outcomes Assessor)
Masking description
Double (participant and outcomes assessor)
Eligibility
Sex/Gender
ALL
Age
50 Years to 80 Years
Healthy volunteers
Yes
Inclusion criteria
* Participation in previous longitudinal cohort studies at the study site * Ability to provide written and verbal informed consent * Fluency in the German language * Stable home situation that allows for reliable application of the intervention for the duration of the study * Ability to apply the intervention for the duration of the study, either alone or with support from a co-habitant * For women: Hormonal contraception, if menstrual cycle is still present or has been present within a year * Good general health status, normal cognitive function
Exclusion criteria
* Failure or inability to give informed consent * Inability to follow the procedures of the investigation * For women: pregnancy or breastfeeding * Presence of sleep disorders (e.g. sleep apnoea, narcolepsy, restless leg syndrome, insomnia, rapid eye movement (REM) sleep disorder) * Shift-work or a home situation that requires several awakenings during the night (e.g. newborn) * History of serious illness likely to interfere with study outcomes * Presence or history of a diagnosed neuropsychiatric illness * Current diagnosis of uncontrolled or poorly controlled diabetes * Current cancer of the brain or unstable cancer undergoing treatment * Evidence of serious atherosclerotic cardiovascular disease
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Correlation between EEG slow wave activity (uV) and cerebrospinal fluid flow (ml/min) from phase contrast MRI | 2 weeks |
| Correlation between EEG slow wave activity (uV) and diffusivity (mm2/s) from diffusion MRI | 2 weeks |
| Correlation between EEG slow wave activity (uV) and perfusion (ml/min/100 ml) from arterial spin labelling MRI | 2 weeks |
| Correlation between EEG slow wave activity (uV) and beta-amyloid (pg/ml) | 2 weeks |
| Correlation between EEG slow wave activity (uV) and tau (pg/ml) | 2 weeks |
Secondary
| Measure | Time frame |
|---|---|
| Correlation between EEG slow wave activity (uV) and attention, assessed with the Trail Making Test (time to completion) | 2 weeks |
| Correlation between EEG slow wave activity (uV) and C-Reactive Protein (mg/L), assessed from a blood sample | 2 weeks |
| Correlation between EEG slow wave activity (uV) and fatigue, assessed via the fatigue severity scale (FSS) questionnaire | 2 weeks |
| Correlation between EEG slow wave activity (uV) and neuro-metabolite levels (mmol) from magnetic resonance spectroscopy | 2 weeks |
| Correlation between EEG slow wave activity (uV) and executive function (summary score, dimensionless) | 2 weeks |
| Correlation between EEG slow wave activity (uV) and TNF-alpha (pg/L), assessed from a blood sample | 2 weeks |
| Correlation between EEG slow wave activity (uV) and sleepiness, assessed with the Epworth Sleepiness Scale questionnaire | 2 weeks |
| Correlation between EEG slow wave activity (uV) and interleukins (pg/L), assessed from a blood sample | 2 weeks |
| Correlation between EEG slow wave activity (uV) and memory function, assessed with the Hopkins Verbal Learning Test (memory score) | 2 weeks |
Countries
Switzerland
Outcome results
None listed