Study Rationale: Sleep problems, like acting out dreams or waking up during sleep, can occur years before people are diagnosed with Alzheimer’s disease or Lewy Body diseases, such as Parkinson’s. Some sleep problems are common across these diseases, while others may be unique. Understanding which sleep changes happen early, and how they differ, may help doctors detect these diseases sooner and develop better treatments.
This project focuses on a tiny but important brain area called the locus coeruleus (LC). The LC helps control sleep, alertness, and memory. It is also one of the first areas damaged in Alzheimer’s and Lewy Body diseases. Damage to the LC may cause or worsen sleep problems and memory decline.
Hypothesis: Using detailed sleep studies, brain scans, blood tests, eye tests, digital sleep technologies, and thinking and memory tests, we will study older adults who are at high risk for these diseases, including those with memory problems (called mild cognitive impairment) and those with a sleep disorder called REM sleep behavior disorder (up to 80% develop Lewy Body diseases) to determine how damage to the LC affects sleep and thinking.
Study Design: We will conduct two streams of research (1) recruiting 100 new participants; and (2) following up existing participants. STREAM 1 will help us understand how having co-pathologies related to Alzheimer's and Lewy Body diseases affects both the LC and sleep, as well as their relationship. STREAM 2 will enable us to determine whether LC integrity predicts cognitive decline and changes to sleep disturbance.
Impact on Diagnosis/Treatment of Parkinson’s disease: This study could identify a new marker to recognize people who may be at higher risk of developing Parkinson’s disease by combining sleep-study changes with measures of locus coeruleus integrity. These early risk signals could help clinicians monitor vulnerable individuals more closely and plan earlier, more targeted support or intervention.
Next Steps for Development: If successful, the next steps will be to develop practical ways to measure LC integrity in clinical settings and combine these with sleep-study markers to identify people at highest risk. This will allow clinicians to use LC-based measures as early warning signs and guide timely monitoring and intervention.