Wearable devices like Apple Watches and Fitbits with movement tracking features could soon be able to alarm about cognitive decline among older adults, claims a new study by researchers at the Johns Hopkins Bloomberg School of Public Health. The study, published in the Journal of Alzheimer’s Disease, is based on a survey of nearly 600 older person participants who wore ActiGraph activity monitors that feature tracking sensor similar to those used in Apple Watches and Fitbits.

The finding showed substantial variations in the movement pattern of those with mild impairment or Alzheimer’s disease when compared to people with normal cognition. This included variation in activity during waking hours and more fragmented activity during afternoons in participants with Alzheimer’s. For the study, researchers used data from a larger, ongoing health research project known as the Baltimore Longitudinal Study of Aging (BLSA). The research project has been going on in the Baltimore area since 1958.

“We tend to think of the physical activity as a potential therapy to slow cognitive decline, but this study reminds us that cognitive decline may in turn slow physical activity — and we might someday be able to monitor and detect such changes for earlier and more efficient testing to delay,” said study lead author Amal Wanigatunga, PhD, MPH, assistant scientist in the Department of Epidemiology at the Bloomberg School.

The scientist pointed at the difference in the activities of the participants during the afternoon. “One of the main symptoms of Alzheimer’s dementia is the “sundowning” phenomenon involving increased confusion and mood changes that start in the afternoon, and it might be that these activity markers are capturing some movement related to these symptoms,” Wanigatunga said.

Researchers have planned to conduct additional studies to ascertain if measurable yet slight changes in everyday activity patterns help in determining mild cognitive impairment and subsequent Alzheimer’s disease dementia.

The use of cognitive movement tracking devices could be a breakthrough in the early diagnosis of Alzheimer’s disease, the most common form of dementia. If researchers are able to predict the development of mild cognitive impairment and, eventually, Alzheimer’s, then principle older individuals who show this change in activity could be assisted with early treatments.