If you live near a busy road, chances are that you may develop hypertension. A new study published in JACC: Advances has shown that the continuous exposure to vehicular noise, including vehicle horns and sirens, does indeed increase the blood pressure.

This prospective study analysed data of 246,477 people, aged 40-69 years, from the UK Biobank database to investigate if chronic exposure to traffic noise is associated with new-onset primary hypertension. All the study subjects were non-hypertensive at study entry and nearly 55% were female. The weighted average 24-hour road traffic noise level ranged from 51.5 dBA to 87.0 dBA. The annual mean PM2.5 level was 10.0 μg/m3 and that of NO2 was 26.5 μg/m3.

Over a median follow-up duration of 8.1 years, 21,140 cases of incident primary hypertension were diagnosed. A rise in the exposure to the average 24-hour road traffic noise level of 10 dBA had a hazard ratio of 1.07. Exposure to >65 dBA of noise was associated with higher risk of hypertension compared to noise levels of less than 55 dBA with HR of 1.13. These associations persisted even after adjusting for fine particulate matter (PM2.5) and nitrogen dioxide (NO2). The risk was highest among those with high exposure to road traffic noise and air pollution.

This study shows that residential exposure to road traffic noise over a long time increased the risk of incident hypertension among middle-aged and elderly people. Moreover, the risk increased in proportion to increase in noise levels demonstrating a dose-response relationship. Poor air quality further enhanced this risk suggesting air pollution also as a risk factor for high BP. These findings add to the accumulating evidence regarding the harmful effects of pollution on human health. They also point out the need to implement public health measures to minimise the impact of noise pollution such as planting more trees, strict enforcement of noise regulating laws, improving roads, and shifting to electric vehicles.

Reference

1. Jing Huang, et al. Road traffic noise and incidence of primary hypertension: a prospective analysis in UK Biobank. JACC Adv. Mar 22, 2023. DOI: 10.1016/j.jacadv.2023.100262.