Aircraft Noise and Incidence of Hypertension

Background: An association between aircraft noise exposure and hypertension prevalence has been suggested but there are no longitudinal studies of this association. Our aim was to investigate the influence of aircraft noise on the incidence of hypertension. Methods: A cohort of 2754 men in 4 municipalities around Stockholm Arlanda airport was followed between 1992-1994 and 2002-2004. The cohort was based on the Stockholm Diabetes Preventive Program; half of the study subjects had a family history of diabetes. Residential aircraft noise exposure ( expressed as time-weighted equal energy and maximal noise levels) was assessed by geographical information systems techniques among those living near the airport. Incident cases of hypertension were identified by physical examinations, including blood pressure measurements, and questionnaires in which subjects reported treatment or diagnosis of hypertension and information on cardiovascular risk factors. Analyses were restricted to 2027 subjects who completed the follow-up examination, were not treated for hypertension, and had a blood pressure below 140/90 mm Hg at enrollment. Results: For subjects exposed to energy-averaged levels above 50 dB( A) the adjusted relative risk for hypertension was 1.19 ( 95% CI = 1.03-1.37). Maximum aircraft noise levels presented similar results, with a relative risk of 1.20 ( 1.03-1.40) for those exposed above 70 dB( A). Stronger associations were suggested among older subjects, those with a normal glucose tolerance, nonsmokers, and subjects not annoyed by noise from other sources. Conclusion: These findings suggest that long-term aircraft noise exposure may increase the risk for hypertension.