Transportation noise and incidence of hypertension.

<bold>Background: </bold>The evidence on exposure to transportation noise and development of hypertension is inconclusive, mostly because of a lack of high quality studies of longitudinal design.<bold>Objectives: </bold>This cohort study aimed at investigating the association between exposure to road traffic, railway or aircraft noise and incidence of hypertension. We also assessed effects of varying lengths of exposure as well as of multiple sources of exposure.<bold>Methods: </bold>Based on the residential histories of a cohort of 4854 men and women from Stockholm County, we estimated the residential exposure to road traffic, railway and aircraft noise in 1, 5 and 10 year time-periods. Hypertension was assessed by blood pressure measurements, information from questionnaires and hospital diagnoses. Extensive information on potential confounders was available from repeated questionnaires and registers. Hazard Ratios (HR) and 95% confidence intervals (CI) of hypertension related to noise exposure was computed from Cox regression models.<bold>Results: </bold>We observed a positive association between aircraft noise exposure and incidence of hypertension with a HR of 1.16 (95% CI 1.08-1.24) per 10 dB Lden 5 years preceding the event. No clear differences in risk were indicated between the three exposure time windows. Road traffic and railway noise were not associated with incidence of hypertension during any of the exposure periods. There appeared to be a particularly high risk of hypertension among persons exposed to both aircraft and road traffic noise ≥45 dB Lden with an HR of 1.39 (95% CI 1.14-1.70).<bold>Conclusions: </bold>Exposure to aircraft noise may result in increased risk of hypertension. [ABSTRACT FROM AUTHOR]