Air pollution-related BP elevation in children may be modified by diet

Children with long-term exposure to particulate matter, sulfur dioxide (SO₂), and ozone (O₃) are at risk of developing higher blood pressure (BP) levels, a recent study has found. In addition, dietary intake may modify these associations.

The investigators included 7,225 primary school children aged 6–12 years from Guangzhou, China, in 2017 and measured BP objectively. They calculated the individual 1-year average concentration of particles with an aerodynamic diameter of ≤2.5 or ≤10 μm (PM_2.5, PM₁₀), SO₂, and O₃ before each BP measurement using inverse distance weighting interpolation according to each home address. Finally, the health effects and potential effect modifications by diet factors were examined after adjusting for covariates using generalized linear mixed-effects models.

The estimated increase in mean systolic BP was 0.92 mm Hg (95 percent confidence interval [CI], 0.05–1.79) per interquartile range increase in O₃. An interquartile range increase in the 1-year mean of O₃ positively correlated with a 20-percent higher likelihood of prehypertension (odds ratio [OR], 1.20, 95 percent confidence interval [CI], 1.06–1.35), while that for an interquartile range increase in the 1-year mean of SO₂ was 26 percent (OR, 1.26, 95 percent CI, 1.04–1.52).

An interquartile range increase in PM_2.5 (OR, 1.33, 95 percent CI, 1.11–1.61), SO₂ (OR, 1.70, 95 percent CI, 1.33–2.16), and O₃ (OR, 1.48, 95 percent CI, 1.20–1.83) exposure also showed a positive association with hypertension.

Notably, children with higher intake of sugar-sweetened beverages showed stronger effect estimates between PM_2.5, SO₂, and O₃ concentration on prehypertension.