Taiwan is becoming a super-aged society, and more older adults are living with Alzheimer's disease. Many people with Alzheimer's experience behavioral and psychological symptoms, such as agitation, sleep problems, or mood changes. These symptoms often lower their quality of life and increase stress for their family caregivers.

This study will test two wearable devices in people with Alzheimer's and their caregivers. One device, called Geneactiv, is a wristwatch that tracks daily activity and sleep. The other device, called Re-Timer, is a light therapy eyewear that may help improve sleep and mood. Researchers will look at how easy the devices are to use, whether participants are willing to wear them for several weeks, and whether the light therapy helps reduce sleep problems or caregiver stress.

The study will also compare information from questionnaires with information collected by the devices. The results may help researchers design future studies using wearable tools to better support people living with dementia and their caregivers.

Taiwan is predicted to become a super-aged society, with people older than 65 years accounting for more than 20% of the population. As the prevalence of Alzheimer's dementia (AD) increases with age, the number of people living with AD will continue to rise. Most of these individuals will experience at least one type of behavioral and psychological symptom of dementia (BPSD). These symptoms not only worsen patients' quality of life but also increase caregiver burden, leading to depression, sleep disturbances, and reduced well-being among caregivers themselves.

Currently, questionnaires completed by caregivers are the main tools used to assess and monitor BPSD. Although validated, these questionnaires can only capture cross-sectional information. In a super-aged society where many caregivers are also older adults with cognitive or physical decline, the accuracy of such assessments may be limited. Previous studies, including our research in the United Kingdom, have shown that even patients with late-stage AD can successfully wear a research-grade actigraphy device (Geneactiv) with good compliance. Device-based measurements offer continuous and objective data and can reveal valuable indicators such as the Sleep Regularity Index (SRI), which may predict both cognitive and physical function over time.

Most treatments for BPSD rely on medications, many of which are not specifically approved for this use and may increase the risk of falls or mortality. Non-pharmacological approaches, such as light-based therapy, provide a promising alternative. The Re-Timer device (an eyewear that emits blue-green light) has demonstrated effectiveness in improving sleep and mood in the general population, with a favorable safety profile. If accepted by individuals with dementia and their caregivers, such wearable devices may reduce sleep problems, agitation, and depressive symptoms, thereby improving the overall quality of life for both groups.

To date, very few studies in Taiwan have applied wearable devices to dementia care. This pilot study therefore aims to evaluate the feasibility and acceptability of two wearable technologies, the Geneactiv actigraphy and the Re-Timer light therapy glasses-among people with Alzheimer's dementia and their caregivers. Ten patient and caregiver pairs will be recruited and followed for twelve weeks. Participants will wear the Geneactiv wrist device for eight weeks and the Re-Timer glasses for four weeks. Sleep quality, behavioral symptoms, caregiver burden, and user experience will be assessed through both questionnaires and device data.

The primary goal is to determine whether dementia patients and caregivers can safely and consistently use these devices. Secondary goals include exploring the preliminary effects of Re-Timer on sleep and BPSD, comparing traditional questionnaire results with digital measurements, and establishing a foundation for future large-scale studies to develop digital biomarkers and technology-assisted interventions for dementia care in Taiwan.

Inclusion Criteria:

• For participants with dementia:

  1. Clinical diagnosis of probable Alzheimer's disease (AD) or mild cognitive impairment (MCI) due to AD, based on established diagnostic criteria.

  2. Presence of at least one prominent behavioral or psychological symptom of dementia (BPSD), including depression, agitation, apathy, or nighttime sleep disturbance.

  3. Prominent is defined as:

     NPI single-item score ≥ 4 (severity × frequency), or NPI-Q severity score ≥ 2, or PSQI total score ≥ 5 (if sleep disturbance is the main symptom).

  4. Stable living arrangement or care environment for at least two weeks before enrollment.

  5. If receiving any pharmacological or non-pharmacological treatments for BPSD, the dosage and frequency must have remained stable for at least two weeks prior to study participation.

  6. Able and willing to provide informed consent; for those lacking decision-making capacity, consent must be obtained from a legally authorized representative.

• For primary caregivers:

  1. Adult primary caregiver of the enrolled participant.
  2. If receiving treatment for caregiver stress, the dosage and frequency must have been stable for at least two weeks before enrollment.
  3. Willing and able to provide informed consent.

Exclusion Criteria:

• Any medical condition that may increase risk during participation, including:

  1. Retinal disease, active use of photosensitizing medications, recent ocular surgery (within 4 weeks), or photosensitivity disorders (e.g., epilepsy).
  2. Unstable physical or mental condition deemed unsuitable by investigators, such as acute delirium or active respiratory infection (including COVID-19)

We will decide if the IPD can be shared before the end of the study.