Understanding Circadian Responses to Light in Persons With Mild Cognitive Impairment

Mount Sinai Health System

Status: Completed

Conditions: Alzheimer Disease; Mild Cognitive Impairment

Treatments: Device: Lighting Intervention Green light; Device: Lighting Intervention Blue light; Other: Dim-light control condition

Study type: Interventional

Funder types: Other; NIH

Identifiers

NCT05411822

GCO 21-0400

R21AG070713 (U.S. NIH Grant/Contract)

Details and patient eligibility

About

The purpose of this research study is to investigate the relationship between light, the thickness of the pigment at the back of your eye, melatonin levels, and memory. The study will investigate whether changing light distribution pattern from "on-axis"' (i.e., directed along the eye's visual axis to the fovea) to "off-axis" (i.e., directed on the periphery of the eye's visual axis) impact melatonin suppression in 24 mild cognitive impairment participants and 24 healthy, age-matched controls.

Full description

Eligible enrolled subjects will be exposed to 4 different lighting conditions in addition to one dark control condition. There will be 5 study session and each one will last for 90 minutes and will be separated by one week. Subjects will collect 3 saliva samples, each one 30 minutes apart for melatonin levels during each study session.

Enrollment: 36 patients

Sex: All

Ages: 55+ years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• mild cognitive impairment
• age matched healthy control
• macular pigment density either < 0.3 or > 0.5

Exclusion criteria

• extensive brain vascular disease
• Parkinson's disease
• bipolar disorder
• seasonal depression
• diabetes
• high blood pressure
• obstructing cataracts
• macular degeneration
• diabetic retinopathy
• use of melatonin supplements
• use of beta blockers
• use of sleep medications
• use of antidepressant medication

Trial design

Primary purpose: Treatment

Allocation: N/A

Interventional model: Single Group Assignment

Masking: None (Open label)

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36 participants in 1 patient group

Participants with Mild Cognitive Impairment

Experimental group

Description:

Every participant experienced all 5 conditions: Blue light (λmax = 451 nm) on axis and off axis. Green light (λmax = 522 nm) on and off axis Dim-light control condition (\< 5 lux at the eye) for 30 min each narrowband source will have distinct lighting distribution patterns but calibrated to deliver the same targeted levels of circadian light (CLA) and circadian stimulus (CS) at the eye.

Treatment:

Other: Dim-light control condition

Device: Lighting Intervention Blue light

Device: Lighting Intervention Green light