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Bedroom light at night measured against incident depressive symptoms in an elderly Japanese cohort
Obayashi K, Saeki K, Kurumatani N (2018) · American Journal of Epidemiology
The longitudinal study reported that bedroom light intensity of 5 lux or more at night was associated with a higher incidence of depressive symptoms (adjusted hazard ratio 1.89) over a median 24-month follow-up.
What they studied
863 community-dwelling adults aged 60 and older, HEIJO-KYO cohort, Nara, Japan
What they found
The longitudinal study reported that bedroom light intensity of 5 lux or more at night was associated with a higher incidence of depressive symptoms (adjusted hazard ratio 1.89) over a median 24-month follow-up.
What it does not establish
This entry reports the study. It is not a statement about any building Sage Co. designs or constructs.
Source
- Obayashi K, Saeki K, Kurumatani N (2018). Bedroom light at night measured against incident depressive symptoms in an elderly Japanese cohort · American Journal of Epidemiology · Read at the source
Last reviewed September 23, 2026.
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