Alzheimer Disease, Mild Cognitive Impairment
Conditions
Brief summary
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.
Detailed 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.
Interventions
DEVICELighting Intervention Blue light
Custom made lighting fixture that will deliver the blue lighting intervention. Blue light (λmax = 451 nm) on axis and off axis.
DEVICELighting Intervention Green light
Custom made lighting fixture that will deliver the green lighting intervention. Green light (λmax = 522 nm) on and off axis
OTHERDim-light control condition
(\< 5 lux at the eye) for 30 min
Sponsors
National Institute on Aging (NIA)
Icahn School of Medicine at Mount Sinai
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
55 Years to No maximum
Healthy volunteers
Yes
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
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Melatonin Levels | post-intervention (60 minutes) on each night of intervention (one night a week for 5 weeks) | Saliva samples collected for melatonin levels for the different conditions. Blue light (λmax = 451 nm) on axis and off axis: for each narrowband source, designated on-axis or off-axis, 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. Green light (λmax = 522 nm) on and off axis: for each narrowband source, designated on-axis or off-axis, 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. Dim-light control condition: (\< 5 lux at the eye) for 30 min |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Participants With Mild Cognitive Impairment 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. | 17 |
| Healthy Age-Matched Control Healthy Age-Matched Control | 19 |
| Total | 36 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Overall Study | Withdrawal by Subject | 2 | 1 |
Baseline characteristics
| Characteristic | Participants With Mild Cognitive Impairment | Healthy Age-Matched Control | Total |
|---|---|---|---|
| Age, Continuous | 59.1 years STANDARD_DEVIATION 7.4 | 58.7 years STANDARD_DEVIATION 7.6 | 58.8 years STANDARD_DEVIATION 7.4 |
| Race and Ethnicity Not Collected | — | — | 0 Participants |
| Sex: Female, Male Female | 15 Participants | 13 Participants | 28 Participants |
| Sex: Female, Male Male | 2 Participants | 6 Participants | 8 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk | EG002 affected / at risk | EG003 affected / at risk | EG004 affected / at risk | EG005 affected / at risk | EG006 affected / at risk | EG007 affected / at risk | EG008 affected / at risk | EG009 affected / at risk |
|---|---|---|---|---|---|---|---|---|---|---|
| deaths Total, all-cause mortality | 0 / 13 | 0 / 13 | 0 / 13 | 0 / 13 | 0 / 13 | 0 / 15 | 0 / 15 | 0 / 15 | 0 / 15 | 0 / 15 |
| other Total, other adverse events | 0 / 13 | 0 / 13 | 0 / 13 | 0 / 13 | 0 / 13 | 0 / 15 | 0 / 15 | 0 / 15 | 0 / 15 | 0 / 15 |
| serious Total, serious adverse events | 0 / 13 | 0 / 13 | 0 / 13 | 0 / 13 | 0 / 13 | 0 / 15 | 0 / 15 | 0 / 15 | 0 / 15 | 0 / 15 |
Outcome results
Primary
Melatonin Levels
Saliva samples collected for melatonin levels for the different conditions. Blue light (λmax = 451 nm) on axis and off axis: for each narrowband source, designated on-axis or off-axis, 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. Green light (λmax = 522 nm) on and off axis: for each narrowband source, designated on-axis or off-axis, 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. Dim-light control condition: (\< 5 lux at the eye) for 30 min
Time frame: post-intervention (60 minutes) on each night of intervention (one night a week for 5 weeks)
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Mild Cognitive Impairment | Melatonin Levels | Blue light (λmax = 451 nm) off axis | 0.9 pg/mL | Standard Deviation 0.46 |
| Mild Cognitive Impairment | Melatonin Levels | Green light (λmax = 522 nm) off axis | 0.82 pg/mL | Standard Deviation 0.39 |
| Mild Cognitive Impairment | Melatonin Levels | Green light (λmax = 522 nm) on axis | 0.73 pg/mL | Standard Deviation 0.14 |
| Mild Cognitive Impairment | Melatonin Levels | Dim Light | 1.53 pg/mL | Standard Deviation 0.7 |
| Mild Cognitive Impairment | Melatonin Levels | Blue light (λmax = 451 nm) on axis | 0.89 pg/mL | Standard Deviation 0.49 |
| Healthy Control | Melatonin Levels | Dim Light | 1.27 pg/mL | Standard Deviation 0.3 |
| Healthy Control | Melatonin Levels | Blue light (λmax = 451 nm) on axis | 0.84 pg/mL | Standard Deviation 0.51 |
| Healthy Control | Melatonin Levels | Blue light (λmax = 451 nm) off axis | 0.68 pg/mL | Standard Deviation 0.21 |
| Healthy Control | Melatonin Levels | Green light (λmax = 522 nm) on axis | 0.73 pg/mL | Standard Deviation 0.3 |
| Healthy Control | Melatonin Levels | Green light (λmax = 522 nm) off axis | 0.79 pg/mL | Standard Deviation 0.24 |