Light and the Effect on Metabolic Syndrome and Alzheimer's Disease

May 6, 2026 updated by: Mariana Figueiro, Icahn School of Medicine at Mount Sinai

Light, Metabolic Syndrome and Alzheimer's Disease: A Non-Pharmocological Approach

This study's main hypothesis is that a delivering a tailored lighting intervention (TLI) will provide a successful means for promoting circadian entrainment and treating metabolic disease and inflammation in patients with mild cognitive impairment (MCI) and Alzheimer's disease (AD) and Alzheimer's disease and related dementias (ADRD). As such, the proposed studies have the potential to provide important insights into the link between AD/ADRD and type 2 diabetes (T2DM) by identifying the disruption of circadian rhythms as a key component in the metabolic impairment. Preliminary data from ongoing studies demonstrates a beneficial effect of light treatment on sleep and depression. If positive results are observed, the potential also exists to transform the manner in which homes, assisted living facilities, and nursing homes are lighted by delivering a simple, practical, non-pharmacological intervention to promote entrainment, improve sleep, and reduce metabolic disease in AD and mild AD MCI patients. This randomized, placebo-controlled, crossover study involving 60 AD/ADRD patients who live in controlled environments (i.e., assisted living facilities and nursing homes), will investigate whether 8 weeks of exposure to a TLI designed to increase circadian entrainment improves sleep, mood, inflammatory markers, and metabolic control, compared to a control, circadian-inactive light.

Study Overview

Status

Completed

Detailed Description

Alzheimer's disease (AD) and type 2 diabetes (T2DM) pose linked, major threats to aging societies worldwide, but the relationship between these two diseases remains poorly understood. Hence, insulin resistance may account for the close epidemiological association between AD and T2DM. A major gap in the understanding of this association, however, is how brain insulin resistance develops in the context of AD. Studies show that circadian disruption impairs metabolic control and increases the risk for diabetes and obesity. Vice versa, disrupted sleep and depression are closely linked to impaired metabolic control and increased diabetes risk in the general population. Notably, AD is associated with circadian disruption, which may be amplified by exposure to irregular light-dark patterns or constant dim light. To what extent circadian disruption contributes to increased diabetes risk in AD remains unclear. Here, the investigator aims to test whether a novel tailored lighting intervention (TLI) designed to promote circadian entrainment in AD patients can improve metabolic control. Preliminary data from ongoing studies demonstrates a beneficial effect of light treatment on sleep and depression. Given the close association of sleep on metabolic control, these data support the hypothesis that light therapy that promotes entrainment can restore metabolic control in AD patients. Specifically, the investigator will test the efficacy of a practical, scientifically sophisticated 24-hour lighting system for increasing circadian entrainment in older adults with AD and related dementias (ADRD). The major goal is to demonstrate that a practical, effective, tailored, nonpharmacological intervention that promotes circadian entrainment can be used to improve sleep, reduce inflammation, and ameliorate glucose intolerance and insulin resistance in AD/ADRD patients.

Aim 1: Test if a TLI that promotes entrainment can improve sleep, depression, inflammation, and glucose tolerance in patients with moderate to late stages ADRD. In a randomized, placebo-controlled, crossover study involving 60 ADRD patients who live in controlled environments, the investigators will investigate whether an 8-week exposure to a TLI designed to increase circadian entrainment (urinary melatonin and activity-rest patterns) will improve inflammation and glucose tolerance (oral glucose tolerance test), and reduce sleep disturbances (actigraphy, Pittsburgh Sleep Quality Index, PSQI) and depressive symptoms (Cornell Scale for Depression in Dementia, CSDD) compared to a control, circadian-inactive light.

Study Type

Interventional

Enrollment (Actual)

61

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

    • New Jersey
      • New Brunswick, New Jersey, United States, 08854
        • Rutgers University
    • New York
      • Albany, New York, United States, 12204
        • Icahn School Of Medicine At Mount Sinai
      • New York, New York, United States, 10029
        • Icahn School of Medicine

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

55 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Diagnosis of mild to moderate Alzheimer's disease or related dementia,
  • sleep disturbance as determined by a score ≥ 5 on the PSQI

Exclusion Criteria:

  • insulin-dependent diabetes,
  • urinary incontinence
  • obstructing cataracts
  • macular degeneration
  • blindness
  • severe sleep apnea or
  • restless leg syndrome (RLS)

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Crossover Assignment
  • Masking: Triple

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Aim 1: Active Intervention then Placebo
Tailored Lighting intervention (TLI). The active TLI will provide high circadian stimulation during the day produced by light sources that provide moderate light levels of spectra that are tuned to the sensitivity of the circadian system. The active lighting intervention will be in place for 8 weeks. Following an 8 week washout period, the participants will see the placebo control intervention for 8 weeks.
Lighting Intervention - active or placebo
Experimental: Aim 1: Placebo Intervention then Active
The placebo lighting intervention is designed to have no effect on the circadian system. The control intervention will be in place for 8 weeks. Following an 8 week washout period, the participants will see the active tailored lighting intervention for 8 weeks.
Lighting Intervention - active or placebo

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change in Glucose Area Under the Curve
Time Frame: once during weeks 1 (baseline), 5, 9, 18 (second baseline), 22, and 26
change in glucose from baseline will be assessed using an oral glucose tolerance test
once during weeks 1 (baseline), 5, 9, 18 (second baseline), 22, and 26

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change in sleep disturbance
Time Frame: once during weeks 1 (baseline), 5, 9, 18 (second baseline), 22, and 26
Change in sleep disturbance will be assessed using the Pittsburgh Sleep Quality Index. The sum of the 7 component scores yields a single global score. A person with a global score above 5 is considered to have sleep disturbances. A higher score indicates worsening sleep disturbance.
once during weeks 1 (baseline), 5, 9, 18 (second baseline), 22, and 26

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Collaborators

Investigators

  • Principal Investigator: Mariana Figueiro, PhD, Icahn School Of Medicine At Mount Sinai

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

November 19, 2018

Primary Completion (Actual)

May 31, 2025

Study Completion (Actual)

May 31, 2025

Study Registration Dates

First Submitted

December 12, 2018

First Submitted That Met QC Criteria

December 13, 2018

First Posted (Actual)

December 17, 2018

Study Record Updates

Last Update Posted (Actual)

May 11, 2026

Last Update Submitted That Met QC Criteria

May 6, 2026

Last Verified

May 1, 2026

More Information

Terms related to this study

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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