Trial results for a study investigating circadian responses to light in persons with Mild Cognitive Impairment and Alzheimer's Disease were posted on ClinicalTrials.gov on 2025-06-24, with 36 participants enrolled.
Background
Alzheimer's Disease and Mild Cognitive Impairment (MCI) are conditions characterized by progressive cognitive decline. Research suggests that disruptions in circadian rhythms, the body's natural sleep-wake cycle, may contribute to the progression of these conditions. Light exposure plays a critical role in regulating circadian rhythms, particularly in influencing melatonin levels, a hormone vital for sleep. Understanding how different patterns of light distribution, such as on-axis (directed to the fovea) versus off-axis (directed to the periphery of the eye's visual axis), affect melatonin suppression in individuals with MCI and healthy controls could offer insights into potential non-pharmacological interventions to improve sleep and cognitive function.
Trial design
This completed study, designated as Phase NA, enrolled 36 participants to investigate conditions including Mild Cognitive Impairment and Alzheimer Disease. The research aimed to explore the relationship between light, retinal pigment thickness, melatonin levels, and memory. Specifically, the study investigated whether changing light distribution patterns from "on-axis" to "off-axis" impacts melatonin suppression. The trial did not list specific interventions in the provided data, but focused on observational measurements related to light exposure and physiological responses. No primary outcomes were explicitly listed in the trial data.
Key results
The trial reported multiple measurements for "Melatonin Levels" in both the Mild Cognitive Impairment group and the Healthy Control group:
- For the Mild Cognitive Impairment group, mean melatonin levels were observed at 0.89 pg/mL (Standard Deviation 0.49), 0.9 pg/mL (Standard Deviation 0.46), 0.73 pg/mL (Standard Deviation 0.14), 0.82 pg/mL (Standard Deviation 0.39), and 1.53 pg/mL (Standard Deviation 0.7).
- For the Healthy Control group, mean melatonin levels were observed at 0.84 pg/mL (Standard Deviation 0.51), 0.68 pg/mL (Standard Deviation 0.21), 0.73 pg/mL (Standard Deviation 0.3), 0.79 pg/mL (Standard Deviation 0.24), and 1.27 pg/mL (Standard Deviation 0.3).
What this means
The posted results provide specific measurements of melatonin levels in participants with Mild Cognitive Impairment and healthy controls. These data points contribute to understanding the physiological responses, particularly melatonin suppression, under various conditions related to light exposure. While the results offer detailed mean values and standard deviations for melatonin levels across different measurements and groups, no comparative analyses or statistical significance between the groups or different light distribution patterns were reported. This study contributes foundational data for future research into how light exposure might be modulated to influence circadian rhythms and potentially impact cognitive health in individuals with Mild Cognitive Impairment and Alzheimer's Disease.
Source
The information regarding these trial results was obtained from ClinicalTrials.gov, a public database of clinical studies. The results for the study NCT05411822, titled "Understanding Circadian Responses to Light in Persons With Mild Cognitive Impairment", were posted on 2025-06-24 on clinicaltrials.gov.