Reducing artificial light at night exposure in the urban environment could decrease light pollution-related hypertension in children.

Elevated blood pressure in children is related to the hypertension in adults. Reducing environmental factors linked to hypertension in children is necessary to prevent hypertension in adults. To investigate the associations between outdoor artificial light at night (ALAN) and blood pressure among children. We recruited 9354 children aged 5-17 in the Seven Northeastern Cities Study between 2012 and 2013. Trained nurses measured their blood pressure with a mercury sphygmomanometer. We defined hypertension as systolic blood pressure (SBP) or diastolic blood pressure (DBP) ≥95th age-sex-height-specific percentile. We geocoded the address of each child and linked it to estimated outdoor ALAN within 500 m (ALAN_-500 m) sourced from the VIIRS/DNB. We utilized generalized linear mixed-effect models to assess the associations of outdoor ALAN and blood pressure and the odds of hypertension. Effect modification by age, sex, weight status, and other potential factors was also explored. The SBP, DBP, and mean arterial pressure at quartile 4 (Q4) of outdoor ALAN_-500 m against Q1 increased in 1.45 (95% CI: 0.31-2.59) mmHg, 2.09 (95% CI: 1.18-2.99) mmHg, and 1.87 (95% CI: 0.99-2.76) mmHg, respectively. The odds of hypertension increased by 30% in Q3 of outdoor ALAN_-500 m compared to Q1 (OR = 1.30, 95% CI: 1.05-1.61). Furthermore, stronger effect estimates were observed among children aged ≤11 years (Q4, β = 5.07[3.28-6.85] vs β = 1.54[0.37-2.71] for DBP) and who were overweight (Q4, OR = 1.95[1.17-3.22] vs OR = 0.89[0.60-1.32] for hypertension). Living in areas with high outdoor ALAN exposure increased the odds of hypertension in children, especially in children aged ≤11 years and overweight. Reducing outdoor ALAN is important for preventing hypertension and controlling blood pressure in children. The study found a positive association between outdoor ALAN and blood pressure and hypertension.