How light exposure affects sleep, mood and alertness in people with glaucoma
Compares sleep, mood and thinking in adults with glaucoma, testing two indoor lights.
Key facts
- Who runs it
- National University of Singapore
- Where
- Singapore, SingaporeSee the 2 sites
- Trial code
- Registry title
- Altered Non-Visual Photoreception in Patients With Glaucoma: Impacts on Sleep, Alertness, Mood, and Cognition
- Status
- Recruiting
- People taking part
- 120 people, planned
- Started
- 5 Sept 2025
- Expected to end
- 31 Dec 2027
- Type of study
- Interventional, 2 groupsOne group gets an existing treatment, for comparison.
- Treatments tested
- Full-spectrum light exposure
- Standard indoor light exposure (Control)
- Record updated
- 12 November 2026
Who can take part
AI summary
From the trial's eligibility criteria. Machine-read from the registry text on this page, so it can be wrong. The registry text below and the trial team decide who can take part.
The trial is looking for adults with primary open-angle glaucoma and for healthy adults to compare with. It studies how light affects sleep, mood, alertness and thinking.
- Age
- Patients with glaucoma: 45 to 75 years. Healthy controls: 50 to 70 years.
- Sex
- All sexes can join.
- Disease stage
- Patients need primary open-angle glaucoma with visual field mean deviation better than -12 dB in at least one eye, and spared central vision. Best-corrected visual acuity must be better than 6/12.
- Earlier treatment
- Participants cannot be taking alpha-adrenergic agonist eye drops or other medicines that could affect the pupil response. They cannot be using sleeping pills.
Main reasons for not taking part
- Other eye diseases, such as macular degeneration, diabetic retinopathy or significant eye injury
- Psychiatric or neurologic disorders, mood disorders, or cognitive impairment or dementia
- Night shift work in the past three months, or recent travel across time zones
- Obstructive sleep apnea, abnormal hearing, or impaired colour vision
- Glaucoma in one eye only, congenital glaucoma, or diabetes treated with medicine
The registry criteria, word for word
Show all 6 criteriaShow less
Who can take part
- Patients with glaucoma must meet all of the inclusion criteria to participate in this study; Patients diagnosed with primary open-angle glaucoma (POAG), as indicated by Humphrey Visual Field (HVF) mean deviation (VFMD) scores better than -12 dB in at least one eye during their most recent clinic visit; Patients having spared central vision; Patients aged 45 to 75 years old; Patients with a best-corrected visual acuity better than 6/12; English-speaking patients; Healthy controls must meet all of the inclusion criteria to participate in this study:
- Participants aged 50 to 70 years old
- Participants with a best-corrected visual acuity better than 6/12
- Normal ophthalmic examination
- English-speaking participants
Who cannot take part
- All subjects (patients and controls) meeting any of the exclusion criteria at baseline will be excluded from participation:; Participants with myopia exhibiting a refractive error exceeding -8.00 diopters (D); Participants with a history of complicated previous intraocular surgery; Participants taking alpha-adrenergic agonist eye drops or other systemic medications or drugs that could affect the pupillary response; Participants with any past or current ocular condition (i.e., age-related retinal diseases (e.g., age-related macular degeneration), retinal pigment epithelium diseases (e.g., Best's disease), diabetic retinopathy, or other optic or generalized neuropathies, significant ocular trauma, or any eye condition affecting fixation (eg. Nystagmus)); Participants diagnosed with cataracts at NS3+ (Nuclear Sclerosis) and above, as well as those with Posterior Subcapsular (PSC) cataracts; Participants with clinically diagnosed psychiatric or neurologic disorders, including cognitive impairment or dementia; Participants with diagnosed mood disorders; Participants engaged in night shift work within the past three months, are currently using sleeping pills, or have recently travelled across timezones within a month prior to the study; Participants with obstructive sleep apnea; Participants with abnormal auditory function; Participants with impaired color vision; Pre-menopausal women (last menstrual period < 1 year) (If applicable); Patients having unilateral glaucoma, congenital glaucoma, non-glaucomatous optic neuropathy, abnormal central vision; Diabetics on treatment
Check if you might fit
Answer for yourself. This is not a decision: only the study team can say whether you can take part.
- Are you between 45 and 75 years old?
Where in Singapore
- National University HospitalSingapore, SingaporeContact: Daniella Mahfoud, MSc.Not yet recruiting
- Singapore National Eye CenterSingapore, SingaporeContact: Janie TayTaking people
About the trial
What the trial wants to find out
The goal of this study is to understand how light sensitivity in the eye affects sleep, mood, alertness, and cognition in adults with glaucoma compared to healthy individuals aged 45-75 years.
Read full original descriptionShow less
The main questions it aims to answer are:
1. Do patients with glaucoma experience poorer sleep, mood, alertness, and cognitive function than age-matched healthy adults? 2. Are these changes related to reduced light sensitivity in special retinal cells called intrinsically photosensitive retinal ganglion cells (ipRGCs), lost in glaucoma? 3. Can exposure to safe, full-spectrum indoor light help improve these functions?
Researchers will compare patients with glaucoma and age-matched healthy controls to see if differences in light sensitivity can explain changes in non-visual light responses (i.e., sleep, mood, alertness, and cognition) and whether full-spectrum light exposure can enhance alertness and wellbeing.
Participants will:
1. Complete eye exams and baseline questionnaires about their sleep, daytime sleepiness, mood, and wellbeing. 2. Wear a wrist-worn device for 8-16 days to record their sleep patterns and light exposure. 3. Visit the laboratory for cognitive and attention tests following exposure to two lighting conditions (randomized, cross-over):
* Standard indoor light (~300 lux) * Full-spectrum light (~1000 lux)
This study will help researchers understand how glaucoma affects the brain beyond vision and explore whether light-based interventions can improve quality of life for people living with glaucoma.
The 2 groups in the trial
- Patients with glaucomaTreatment being tested
Patients undergoing both control and intervention light exposure in a cross-over randomized design.
Treatment: Full-spectrum light exposure and Standard indoor light exposure (Control)
- Controls (healthy adults)Existing treatment, for comparison
Healthy adults following the same procedures compared to patients with glaucoma
Treatment: Full-spectrum light exposure and Standard indoor light exposure (Control)
Questions to ask the study team
- How often do I need to come in, and for how long each time?
- Are travel costs paid?
- Can I keep my own doctor?
- What happens if I want to stop?
Contact the study team: see the registry record → Contacts and Locations
Print a page for my doctorData and sources
- Registry record
- Listed on ClinicalTrials.gov.
- Official title
- Altered Non-Visual Photoreception in Patients With Glaucoma: Impacts on Sleep, Alertness, Mood, and Cognition
- Plain-language title
- How light exposure affects sleep, mood and alertness in people with glaucomaGenerated from the registry record. The registry title is the official one.
- AI summary
- From the trial's eligibility criteria. Read by machine on 12 November 2026.
- Fit questions
- Built from NCT07364929, who can take part
- Record updated
- 12 November 2026