Study of some cardiovascular parameters after chronic exposure to noise.

Research has focussed lately on noise as a risk factor for cardiovascular diseases. Recent findings, which have not been well confirmed, indicate that it does appear to affect heart rate, blood pressure and the electrocardiogram. This study involved two groups of subjects (with 75 and 225 in each, respectively) classified on the basis of different intensity of exposure to noise. Non-occupational risk factors studied (cholesterol, blood glucose, smoking, body mass index, family history of cardiovascular problems) revealed no significant differences between the two groups. Audiometric deficits and time exposure to noise were also studied. Blood pressure was measured at rest, an electrocardiogram was taken, and a cycloergometric stress test was made. The prevalence of hypertension and electrocardiographic modifications in basal conditions and under the stress test differed to a significant extent in relation to the different exposures to noise.