Overview
- UK Biobank participants wore wrist light sensors for one week between 2013 and 2016, with about eight to nine years of follow-up for incident cardiovascular disease.
- People in the brightest overnight exposure group had higher risks, including 56% for heart failure, 47% for heart attack, 32% for coronary artery disease, 32% for atrial fibrillation, and 28% for stroke.
- Risk increased in a dose–response manner and remained significant after adjustments for demographic, socioeconomic and lifestyle factors, sleep measures, shift work, and polygenic risk.
- The authors stress the observational design, limited participant diversity, brief monitoring period, and unknown light sources, calling for interventional studies and clearer lighting guidance.
- Researchers and clinicians suggest reducing nighttime light and reinforcing daytime cues, using blackout curtains, dim or warm lighting before bed, limiting screens, and seeking morning daylight.