Description

Over 500,000 Canadians are currently living with dementia and this is predicted to reach one million in the next two decades. With no effective cures, there is an urgent need to identify and treat causal risk factors. Sleep and circadian rhythm disruption, including sleep deprivation, sleep fragmentation, sleep apnea, and abnormal circadian rhythms, are common. In model organisms, they accelerate development of dementia-associated neuropathologies and accumulating evidence suggests that in older adults they may be associated with a greater risk of dementia and dementia-related structural brain changes.

Sleep apnea is characterized by recurrent episodes of absent (apneas) or reduced (hypopneas) airflow in sleep, accompanied by hypercarbia and hypoxemia, and terminated by arousal and resumption of normal breathing. Sleep apnea is common in adults with Alzheimer's Disease (AD) and other dementias. The prevalence of moderate sleep apnea (apnea hypopnea index (AHI) > 15) in patients with mild AD is estimated at 68% and may be higher in moderate to severe AD. Moreover, a recent meta-analysis suggested that patients with AD have a five-fold increased odds of presenting with sleep apnea than adults with normal cognition.

The overall goal of this study is to test the hypothesis that sleep apnea is associated with accelerated cognitive decline in older adults at risk for dementia. The investigators will measure sleep apnea and its cardiovascular consequences at baseline and 12 months later and relate this to cognitive function at the same time points. To achieve this, the investigators will study participants enrolled in the Canadian Therapeutic Platform Trial for Multidomain Interventions to Prevent Dementia (CTU) and affiliated trials. The CTU is a Canada-wide study of older adults at risk for dementia, being undertaken by the Canadian Consortium on Neurodegeneration that will begin recruitment in May 2022. It, and affiliated trials, are anticipated to recruit 750 participants from May 2022-April 2024.

In clinical practice, sleep apnea is diagnosed using inpatient polysomnography. However, this is not feasible for many older adults. To overcome this barrier, the investigators will utilize an investigational vital signs monitor - the Advanced NeoNatal Epidermal (ANNE) Vital Sign System (Sibel Inc., Evanston, IL, USA).

The ANNE Vital Sign System is a wireless remote monitoring system consisting of two flexible, soft, and skin-mounted electronic devices for use by researchers and healthcare professionals for continuous collection of physiological data in home and professional healthcare settings. The ANNE Vital Sign System integrates simultaneous synchronized ambulatory measurement of electrocardiography, photoplethysmography with derived pulse oximetry, pulse arrival time with derived beat-to-beat blood pressure, triaxial accelerometry, respiratory rate, and temperature, which would enable accurate measurement of sleep apnea. Indeed, in compelling in-laboratory preliminary data, the investigators show the capacity for the ANNE Vital Sign System to detect and characterize sleep apnea in older patients. The ANNE Vital Sign System is non-invasive, flexible, easy to use, comfortable, and skin safe.

A separate 8-site Canadian in-lab study of the ANNE Vital Sign System is already underway, with participants undergoing diagnostic polysomnography per usual care or in the context of existing research projects approved by an institutional ethics board. ANNE Vital Sign System has an approved Investigational Testing Authorization (ITA) for this in-lab study (ITA application number 319430, approved December 11, 2020).

CTU recruiting sites will refer potential participants to Sunnybrook Research Institute (SRI) to obtain informed consent and then prepare shipment of ANNE Vital Sign System and instructions to participant. After study equipment and materials are shipped to and received by the participant, study staff will instruct the participant on the proper application and use of the ANNE Vital Sign System over remote video-conference. Specifically, study staff will instruct the participant to attach the two sensors of the ANNE Vital Sign System according to manufacturer recommendations. Participants will wear the sensors for 24 hours before removing it themselves at home and shipping back to Sunnybrook Research Institute. This procedure will be completed at two time points: Baseline and 12 months later.

        For reference, inclusion criteria of CTU affiliated studies from which we will recruit may
        include, but are not limited to, the following list:
          1. Ages 60-85
          2. Sufficient proficiency in English or French
          3. Technical ability to participate in remote assessments
          4. Meets criteria for No Dementia and one of the following (according to CCNA Criteria):
               1. Cognitively Unimpaired
               2. Cognitively Unimpaired plus Subjective Cognitive Impairment
               3. Mild Cognitive Impairment (MCI)
          5. AND Classified as being at increased risk of dementia based on at least one of the
             following: a. First-degree family history of dementia b. Self-Reported or documented
             current and/or history at midlife (45-60 years) of the following risk factors: i.
             Hypertension ii. Hypercholesterolemia iii. Body Mass Index > 30 kg/m2 iv. Physical
             Inactivity v. Insomnia vi. Vascular-metabolic risk
        Exclusion Criteria:
          1. Known nickel allergy
          2. Known cardiac implantable device
          3. Known arrhythmias
          4. Otherwise unable to use the sensors; for example, finger amputations
        For reference, exclusion criteria of CTU affiliated studies from which we will recruit may
        include, but are not limited to, the following list:
          1. Participants who, in the opinion of the investigator, are not able to complete trial
             procedures remotely or adhere to the schedule of study assessments.
          2. Individuals where English or French is not sufficiently proficient for remote clinical
             assessment.
          3. Individuals who do not have the technical ability. Technical ability is defined as
             having computer and internet access; ability to send and receive emails; ability to
             participate in remote assessments.
          4. Individuals who have a clinical diagnosis of Dementia
          5. Clinical Dementia Rating (CDR; telephone/video-conference administration) Score of >1
             or having a diagnosis of dementia based on DSM-IV criteria
          6. Total Score on the Montreal Cognitive Assessment (MoCA; video-conference
             administration) <13