The Cardiovascular Effects of Noise

Abstract

Background: Traffic noise can induce chronic stress reactions and thereby elevate the risk of cardiovascular disease. The responsible pathophysiological mechanisms are as yet unclear.

Methods: This review is based on publications retrieved by a selective search in PubMed for epidemiological and experimental studies (2007-2018) on the relation between noise and the risk of cardiovascular disease. The search terms were "noise AND cardiovascular effects" and "noise cardiovascular effects."

Results: Epidemiological studies have shown that noise caused by air, road, and rail traffic has a dose-dependent association with elevated cardiovascular morbidity and mortality. A current meta-analysis commissioned by the World Health Organization concludes that road-traffic noise elevates the incidence of coronary heart disease by 8% per 10 dB(A) increase starting at 50 dB(A) (95% confidence interval [1,01; 1,15]). Traffic noise at night causes fragmentation of sleep, elevation of stress hormone levels, and oxidative stress. These factors can promote the development of vascular dysfunction (endothelial dysfunction) and high blood pressure, which, in turn, elevate the cardiovascular risk.

Conclusion: Traffic noise, and air-traffic noise in particular, is an important cardiovascular risk factor that has not been sufficiently studied to date. Preventive measures are needed to protect the population from the harmful effects of noise on health.

Figure 1

Examples of sound levels from various sources. The dB(A) scale is a logarithmic scale, so that an increase/decrease of 3 dB(A) means doubling/halving of the sound level. An increase/decrease of 10 dB(A) is perceived as doubling/halving of loudness. In circumstances of long-term exposure to over 55 dB(A) weighted day–evening–night levels (L_den), with an increment of 5 dB(A) for the evening and 10 dB(A) for the night, the risk of cardiovascular disease rises (13, 20). (Modified from Münzel et al. [39]. Reproduced with the permission of the publisher. Copyright © 2017, Oxford University Press)

Figure 2

The noise effect model of Babisch et al. (9) adjusted according to Münzel et al. (4). Both persistent and acute exposure to noise leads to increased development of cardiovascular risk factors (raised blood pressure, increases in blood lipids and blood sugar, greater cardiac output, increased blood viscosity, and activation of blood coagulation), mediated by mental and physiological stress reactions. In the long term, this leads in turn to the clinical manifestation of cardiovascular diseases such as hypertension, coronary heart disease, heart failure, arrhythmia, and stroke. (Modified from Münzel et al. [4]. Reproduced with the permission of the publisher. Copyright © 2014, Oxford University Press)

Figure 3

Dose–response relationships for noise and cardiovascular disease. L_den is the weighted day–evening–night sound level, with an increment of 5 dB(A) for the evening and 10 dB(A) for the night. CVD, cardiovascular disease; Hyp, hypertension. (Modified from Münzel et al. [4]. Reproduced with the permission of the publisher. Copyright © 2014, Oxford University Press)