Study of a mobile health intervention to promote healthy light exposure in older adults in Singapore

A randomised, double-blind trial of a chronotherapeutic mobile health behaviour change intervention targeting optimal light exposure among older adults aged =60 years in Singapore (LightSPAN)

Status

Active, not recruiting

Phases

Unknown

Study type

Interventional

Source

ISRCTN

Registry ID

ISRCTN12391932

Enrollment

Registered

2025-09-05

Start date

2025-08-18

Completion date

Unknown

Last updated

2026-05-25

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Circadian rhythm disruption, sleep disturbances, mood and cognitive decline, frailty, and vitamin D deficiency associated with suboptimal light exposure in older adults Nervous System Diseases

Interventions

This study is evaluating the effectiveness of a mobile health intervention (LightUP app) compared with a placebo app in optimizing light exposure behaviour and improving physiological, cognitive, and

Eligibility

Sex/Gender

All

Age

60 Years to 100 Years

Inclusion criteria

Inclusion criteria: 1. Aged =60 years 2. Residing in Singapore; community-dwelling and not institutionalised or living in nursing homes 3. Capable of independent mobility (with or without assistive devices) 4. Capable of functional independence (Lawton Instrumental Activities of Daily Living [IADL] score: >8 for females, >5 for males) 5. Proficient in communication, reading, and writing in English 6. Owns a smartphone 7. Not currently enrolled in other ongoing mobile health interventional studies

Exclusion criteria

Exclusion criteria: 1. Cognitive impairment (Montreal Cognitive Assessment [MoCA] 6) 3. Significant physical impairment impacting daily activities 4. Severe terminal illness or psychiatric condition interfering with daily function 5. Visual impairment, diagnosed eye diseases, or ocular abnormalities as assessed by a licensed optometrist 6. Uncorrected hearing impairment

Design outcomes

Primary

Measure	Time frame
1. The effectiveness of the LightUP app in improving light exposure behaviour in older adults, measured using data collected from the ActLumus light logger over the 4-week baseline period, the 12-week intervention period, and the 2-week follow-up monitoring period 3. Daily time above 250 lx melanopic equivalent daylight illuminance (minutes/day) during daytime, measured using the ActLumus light logger over the 12-week intervention, corrected to baseline and analysed with linear mixed models, as well as long-term differences, assessed in the follow-up monitoring period relative to baseline	—

Measure

Time frame

1. The effectiveness of the LightUP app in improving light exposure behaviour in older adults, measured using data collected from the ActLumus light logger over the 4-week baseline period, the 12-week intervention period, and the 2-week follow-up monitoring period 3. Daily time above 250 lx melanopic equivalent daylight illuminance (minutes/day) during daytime, measured using the ActLumus light logger over the 12-week intervention, corrected to baseline and analysed with linear mixed models, as well as long-term differences, assessed in the follow-up monitoring period relative to baseline

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Secondary

Measure	Time frame
1. Sleep parameters (total sleep time, sleep efficiency, sleep onset latency, wake after sleep onset) measured using the Garmin Vivosmart 5 actigraphy and sleep diaries continuously over the study period. 2. Sleep quality measured using the Pittsburgh Sleep Quality Index (PSQI) at baseline (week 4), mid-point (week 10), endpoint (week 16), and follow-up (week 28). 3. Circadian rest-activity rhythms (interdaily stability, intradaily variability, relative amplitude) measured continuously using Garmin data over the study period. 3. Mood states measured using the Brief Mood Introspection Scale (BMIS) at baseline (week 4), mid-point (week 10), endpoint (week 16), and follow-up (week 28). 4. Daily mood ratings measured using the Single-Item Mood Scale (SIMS) throughout the study period. 5. Weekly mood ratings measured using the Visual Analogue Mood Scale (VAMS) over the 12-week intervention period. 6. Cognitive performance measured using the NIH Toolbox at baseline (week 4), mid-point (week 10), endpoint (week 16), and follow-up (week 28), including Dimensional Change Card Sort, Flanker Inhibitory Control and Attention, Oral Symbol Digit, Picture Sequence Memory Form A or B, Rey Auditory Verbal Learning, Rey Auditory Verbal Learning Delay, and Pattern Comparison Processing Speed Test. 7. Frailty measured at baseline (week 4), mid-point (week 10), endpoint (week 16), and follow-up (week 28) using five criteria: unintentional weight loss, exhaustion identified with two items from the Centre for Epidemiologic Studies for Depression Scale (CES-D), low physical activity assessed with the Physical Activity Scale for the Elderly (PASE), slowness assessed with the 5-meter walking time test, and weakness assessed with dominant hand grip strength. 8. Physical activity (daily step count, moderate-to-vigorous activity, sedentary behaviour) measured continuously using Garmin data throughout the study period and PASE. 9. Body composition (weight, height, body fat percentage, muscle mas	—

Measure

Time frame

1. Sleep parameters (total sleep time, sleep efficiency, sleep onset latency, wake after sleep onset) measured using the Garmin Vivosmart 5 actigraphy and sleep diaries continuously over the study period. 2. Sleep quality measured using the Pittsburgh Sleep Quality Index (PSQI) at baseline (week 4), mid-point (week 10), endpoint (week 16), and follow-up (week 28). 3. Circadian rest-activity rhythms (interdaily stability, intradaily variability, relative amplitude) measured continuously using Garmin data over the study period. 3. Mood states measured using the Brief Mood Introspection Scale (BMIS) at baseline (week 4), mid-point (week 10), endpoint (week 16), and follow-up (week 28). 4. Daily mood ratings measured using the Single-Item Mood Scale (SIMS) throughout the study period. 5. Weekly mood ratings measured using the Visual Analogue Mood Scale (VAMS) over the 12-week intervention period. 6. Cognitive performance measured using the NIH Toolbox at baseline (week 4), mid-point (week 10), endpoint (week 16), and follow-up (week 28), including Dimensional Change Card Sort, Flanker Inhibitory Control and Attention, Oral Symbol Digit, Picture Sequence Memory Form A or B, Rey Auditory Verbal Learning, Rey Auditory Verbal Learning Delay, and Pattern Comparison Processing Speed Test. 7. Frailty measured at baseline (week 4), mid-point (week 10), endpoint (week 16), and follow-up (week 28) using five criteria: unintentional weight loss, exhaustion identified with two items from the Centre for Epidemiologic Studies for Depression Scale (CES-D), low physical activity assessed with the Physical Activity Scale for the Elderly (PASE), slowness assessed with the 5-meter walking time test, and weakness assessed with dominant hand grip strength. 8. Physical activity (daily step count, moderate-to-vigorous activity, sedentary behaviour) measured continuously using Garmin data throughout the study period and PASE. 9. Body composition (weight, height, body fat percentage, muscle mas

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Countries

Singapore

Contacts

Public ContactResshaya Murukesu

resshaya.murukesu@tum-create.edu.sg+65 66014015

Outcome results

None listed

Source: ISRCTN (via WHO ICTRP) · Data processed: May 30, 2026