TOPLINE:

Hypothetically reducing the concentrations of particulate matter < 2.5 μm (PM2.5) lowered the 6-year risk of developing prehypertension or hypertension in children, and increasing environmental greenness provided additional protective effects.

METHODOLOGY:

• Researchers analysed data of 2385 children aged 2-9 years (mean age, 5.98 years; 48.6% girls) across European countries to investigate whether hypothetical interventions in air pollution and greenness influenced the future occurrence of prehypertension or hypertension.
• Concentrations of air pollutants, including PM2.5, black carbon, and nitrogen dioxide, were estimated at residential addresses. Environmental greenness was quantified using the normalised difference vegetation index (NDVI).
• Models hypothetically reduced the concentrations of each air pollutant and increased the NDVI by various percentages and compared the effects with no intervention.
• The combined incidence of prehypertension and hypertension, defined as systolic and/or diastolic blood pressure ≥ 90th percentile, was assessed over a period of 6 years.

TAKEAWAY:

• Hypothetically reducing the concentrations of PM2.5 to ≤ 10 μg/m³ reduced the risk of developing prehypertension or hypertension from 14.4% to 3.7% — a reduction of 10.7 percentage points compared with no intervention (95% bootstrap CI, -14.1 to -5.7).
• Reducing the concentrations of black carbon or nitrogen dioxide produced smaller or non-significant effects.
• Increasing environmental greenness to ≥ 0.6 NDVI reduced the risk of developing prehypertension or hypertension by 1.48 percentage points (95% bootstrap CI, -2.93 to -0.41).
• The protective effects of lowering the concentrations of PM2.5 and black carbon were generally due to reductions in systolic blood pressure.

IN PRACTICE:

"Our findings may motivate policymakers to ensure adherence to recommended levels of air pollutants and to increase environmental greenness as measures that can help to prevent hypertension among children and adolescents as well as cardiovascular disease burden in later life," the researchers reported.

SOURCE:

This study was led by Maike Wolters, PhD, Leibniz Institute for Prevention Research and Epidemiology – BIPS, Bremen, Germany. It was published online on September 23, 2025, in the European Journal of Preventive Cardiology.

LIMITATIONS:

Blood pressure was measured only once during each survey wave instead of multiple occasions. The NDVI could not differentiate between different types of vegetation, such as parks or crops, and did not provide information on accessibility and time spent in green spaces. Researchers lacked information on indoor and non-residential exposures to pollutants and parental smoking.

DISCLOSURES:

This study received funding from multiple sources, including Innovation Fund Denmark, Federal Ministry of Education and Research (Germany), and National Centre for Research and Development (Poland), under the Partnership Fostering a European Research Area for Health. Additional funding was received from the European Union and the European Community within the Seventh RTD Framework Programme. The authors reported having no conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.