Abstracts: ISEE 19th Annual Conference, Mexico City, Mexico, September 5–9, 2007
Can Exposure to Noise Affect the 24 Hour Blood Pressure Profile? Results From the Hyena Project
To study the association between acute and chronic exposure to transportation noise and blood pressure (BP) reduction during nighttime sleep.
Material and Methods:
Twenty-four-hour ambulatory BP measurements at 15-minute intervals were carried out on 148 persons living near 4 major European airports. Noise was measured continuously during the subjects’ night sleeping period in their bedroom with a noise-meter sampling every 125 milliseconds and recorded on a digital MP3 recorder. Awake/sleeping periods and calculation of BP dipping were based on a sleep log (daytime sleep excluded). “Acute exposure” noise indicators were calculated for each subjects’ study night and included equivalent indoor noise level, source-specific (aircraft, road traffic, other) equivalent indoor noise levels, total number of events (defined when indoor LAmax >35 dB) and source-specific number of events. Long-term exposure noise indicators included the annual averages outdoor L(A)eq24h for aircraft and road traffic, based on the participants’ residence. Multivariate linear regression analysis was applied after adjusting for sex, age, BMI, smoking habits, and working status on the day of the measurements.
The pooled estimates from all 4 centers show that the only noise indicator associated consistently with smaller BP dipping is higher road traffic noise. The effect is statistically significant only on diastolic dipping and shows that a 5 dB increase in measured road traffic noise during the study night is associated with 0.8% less dipping in diastolic BP. Other variables expressing noise exposure were not associated with BP dipping in a consistent way across the 4 centers.
Road traffic noise exposure appears to be associated with smaller dipping. However, there are no a priori reasons to hypothesize that aircraft noise should have a different effect than traffic noise and thus the lack of a consistent association with noise from aircrafts may be a result of the relatively limited power.
Abstracts published in EPIDEMIOLOGY have been reviewed by the organizations or EPIDEMIOLOGY Affiliate Societies at whose meetings the abstracts have been accepted for presentation. These abstracts have not undergone review by the Editorial Board of EPIDEMIOLOGY.© 2008 Lippincott Williams & Wilkins, Inc.