Noise and Air Pollution as Risk Factors for Hypertension: Part I-Epidemiology

Abstract

Traffic noise and air pollution are 2 major environmental health risk factors in urbanized societies that often occur together. Despite cooccurrence in urban settings, noise and air pollution have generally been studied independently, with many studies reporting a consistent effect on blood pressure for individual exposures. In the present reviews, we will discuss the epidemiology of air pollution and noise effects on arterial hypertension and cardiovascular disease (part I) and the underlying pathophysiology (part II). Both environmental stressors have been found to cause endothelial dysfunction, oxidative stress, vascular inflammation, circadian dysfunction, and activation of the autonomic nervous system, thereby facilitating the development of hypertension. We also discuss the effects of interventions, current gaps in knowledge, and future research tasks. From a societal and policy perspective, the health effects of both air pollution and traffic noise are observed well below the current guideline recommendations. To this end, an important goal for the future is to increase the acceptance of environmental risk factors as important modifiable cardiovascular risk factors, given their substantial impact on the burden of cardiovascular disease.

Keywords: air pollution; cardiovascular diseases; inflammation; noise; oxidative stress; risk factors.

Figure 1.

Estimated global excess mortality with cardiovascular causes attributable to air pollution in North America. Europe and Asia.

Figure 2.

Mean global, and country-level loss of life expectancy from ambient air pollution (A) and tobacco smoking (B) of death refers to 2015. (C) Age distribution of excess mortality from ambient air pollution. Globally, about 25% of the attributable mortality occurs at the age of <60 years: in Europe, about 11%, and in Africa, about 55%. (D) Percentage of global life expectancy loss from air pollution by different disease categories. CEV,cerebrovascular disease; COPD,chronic obstructive pulmonary disease; IHD,ischemic heart disease; LC,lung cancer; LRI,lower respiratory infections; NCD,non-communicable diseases. A-D adapted from with permission. Copyright ^© 2020, Oxford University Press.

Figure 3.

(A) Association between brachial-ankle pulse wave velocity (baPWV) and the number of daytime and nighttime noise events by quartiles. Adapted from with permission from the authors. (B) Odds ratios (ORs) of hypertension in relation to aircraft noise (5-dB-categories). L_Aeq,16h, and L_night were included separately in the model. Adjusted for country, age, sex, body mass index, alcohol intake, education, and exercise. The error bars denote 95% confidence intervals (CIs) for the categorical (5-dB) analysis. The blue and red lines show the ORs and corresponding 95% CIs for the continuous analyses. Adapted from with permission from the authors.