Association between road traffic noise and prevalence of coronary heart disease.

There is an established evidence that exposure to high levels of road traffic noise is associated with elevated risk of coronary heart disease (CHD). The results however have been heterogeneous and mostly inconclusive. The present investigation aimed to examine this association in adult subjects, with a secondary aim of identifying potentially vulnerable sub-populations. Similar studies have never been reported from Indian population. For exposure assessment, the time-weighted road traffic noise indicator, L den, was used as a continuous and categorical predictor. A cross-sectional study was designed, and sociodemographic and lifestyle- and health-related characteristics were recorded for 909 (533 females and 376 males) subjects aged 18-80 years. The respondents living in areas with L den < 60 dB(A) were designated as the reference group. Odds for self-reported CHD in relation to traffic noise exposure were estimated by univariate and multifactorial logistic regression with adjustments for potential confounders and effect modifiers. The adjusted odds ratio (OR) for self-reported CHD was 1.72 (95 % CI 1.36-2.19) per 5 dB(A) increase of L den (range 55-80 dB(A)). A gender-related risk difference was observed among male (OR 1.47 (1.07-2.02)) and female (OR 1.83 (1.27-2.65)) respondents. A stronger effect for subjects in the age group 55-64 years old was found, with age, residence period, body mass index, and self-reported stress being significant confounders. This study suggests epidemiological evidence that exposure to road traffic noise of L den > 65 dB(A) may be associated with occurrence of CHD in adult subjects. A trend was observed indicating increasing risk with higher exposure levels. The study results are also suggestive of higher risk of outcome among those with other chronic ailments (diabetes, pulmonary, or renal issues) and residing in the same location in excess of 15 years. Orientation of bedroom windows was identified as a significant effect modifier.