Author(s): Lercher Peter, De Coensel Bert, Dekoninck Luc, Botteldooren Dick
The current evidence supporting an association between traffic noise exposure and hypertension is mixed. Hypertension is the most prevalent and preventable ill health condition in adults of OECD countries and an established risk factor for more severe cardiovascular endpoints such as myocardial infarction and stroke. Several methodological flaws hinder a proper assessment. Among those are study design issues, hypertension assessment, lack of handling of other risk and contextual factors in the regression models and eventually misclassification of exposure. Studies in acoustics have demonstrated that standard indicators of sound intensity (Leq 16hrs, Lden) may not always suffice to explain effects of noise on humans. Studies on annoyance responses revealed that indicators of noise characteristics and dynamics are likewise important. Moreover, standard noise mapping methods do often not include all roads and are known to underestimate the real exposure on the quiet sides and the exposure from the neighborhood.\nIn a secondary analysis of a cross-sectional survey (N=2002, 80% participation) we were able to derive several dynamic noise indicators from original sound recordings for 1500 participants. In addition, we included necessary medical and contextual factors in the multiple logistic regression models to evaluate the relative potency of the noise indicator contribution. Eventually, we evaluated both, diagnosis and medication use of hypertension as separate health outcome indicators.\nOverall, an association between several noise indicators and hypertension diagnosis and medication could be confirmed after adjustment for a basic set of potential confounders (age, sex, bmi, health status, sensitivity, education, area). The applied noise indicators performed slightly different regarding the traffic sources. With Lnight even a significant relation with highway noise was observed. The dynamic indicators fit slightly better with traffic sources where higher fluctuation (main road, railway) and contexts with lower background noise levels exist.
Name: Prof Peter Lercher