One thing almost all WHOOP members have in common is a performance-oriented mindset. And while it comes in many shapes and sizes, one aspect of this that you might not immediately associate with WHOOP is long-term cognitive performance. But for the last two years, WHOOP has been used by the Weill Cornell Department of Neurology and the Weill Cornell Alzheimer’s Prevention Clinic to understand how neurodegenerative diseases might show up in sleep data, even prior to the onset of cognitive symptoms.
You can read their full publication here, but we explain the key findings and what they mean for you and your WHOOP data below.
Alzheimer’s Disease (AD) is one of the most prevalent neurodegenerative diseases. While it remains incurable, AD develops gradually and medical intervention can slow the disease’s progression. In theory, the disease starts doing permanent neurological damage long before clinically significant symptoms present. So, if we knew that someone was in this early stage, disease halting interventions could be started, resulting in a person’s symptom-free years being extended and their quality of life improved.
This is where our study comes excitingly into play.
The Alzheimer’s Prevention Clinic provided study subjects who were at risk of AD due to a family history, most of whom (72.7%) were healthy and asymptomatic. The research team at Weill Cornell used machine learning to divide the study’s 34 subjects into two groups based on biometric data collected by WHOOP. They then compared the two groups’ performance on a battery of cognitive testing, as well as on blood lipid and inflammatory markers - two tests typically used to stage AD severity.
Interestingly, there was no difference in the data collected from blood testing but there was a difference in cognitive test performance. What this result seems to suggest is that non-invasive WHOOP data collected over time correlated with cognitive test performance better than did invasive laboratory testing.
Most significantly, the Weill Cornell research team found that Group 1 spent a larger proportion of their sleep in slow wave sleep than did Group 2, and scored higher on a cognitive test associated with the health of the prefrontal cortex. This result is further supported by research done by another group prior to the present study which also linked reduced slow wave sleep to atrophy of the prefrontal cortex. However, this was the first study to show that slow wave sleep identified by a wrist-worn wearable device correlated with performance on this cognitive test.
While this study was small and there is still more research to be done, what it suggests is that long-term tracking of sleep, and specifically percent of time spent in slow wave sleep, could reveal an early warning sign of AD that most people aren’t currently being tested for. According to the study’s authors, this could enable clinicians to begin risk reduction interventions earlier than they are currently able to.
This isn’t just exciting for us here at WHOOP, it’s also really exciting news for everyone concerned about cognitive decline. When asked about satisfaction with wearing WHOOP device, 88.9% of the study participants reported that after the 6 month study they wanted to keep wearing the device. While this is obviously a flattering validation of the comfort and usability of our product, it is also proof that using non-invasive technologies, such as WHOOP, is an effective and user-friendly way to monitor long-term changes in sleep trends and therefore in wellness.
Some research suggests that interventions to increase slow wave sleep could mitigate cognitive decline due to aging and AD. Savvy WHOOP members might be surprised to learn that slow wave sleep, which we generally talk about as being associated with physical recovery, is so significant in the AD pathway. While this might initially be unexpected, it’s not in any way contradictory of our understanding of slow wave sleep. Although AD impacts cognitive performance, the actual impairment is largely attributed to the physical accumulation Beta Amyloid plaques, and during slow wave sleep we physically clear out the plaques that accumulated throughout the day. If someone is not getting enough slow wave sleep, the plaques can accumulate faster than they are cleared, resulting in a net increase which can really add up over time.
For more on the study, check out our podcast with Dr. Richard Isaacson, Director of the Alzheimer’s Prevention Clinic at Weill Cornell. And for any of you who may be newly motivated to improve your sleep, you can find a refresher on some of our recommendations in our podcasts and other sleep articles on The Locker.