A dose-response relationship for occupational noise-induced hypertension

The effect of industrial noise on hypertension prevalence was studied in a group of 1101 female workers in a textile mill in Beijing in 1985. Essentially the entire group had worked in specific workshops in this mill for their full working lives and all had worked for at least five years. The noise levels within the plant were assessed and appear to have been constant since 1954 resulting in a well-defined noise exposure for these workers. A cross-sectional design was used in which blood pressures were determined and questionnaires administered to the workers over a two month period. In addition to demographic information, data was gathered on personal and family history of hypertension, current use of prescription drugs, alcohol, tobacco and salt in the diet. Logistic regression indicated that noise exposure is a significant determinant of hypertension prevalence, but third in order of importance behind family history of hypertension and salt use. Each of the predictor variables exerted an independent influence on risk of hypertension. Cumulative exposure to noise was not an important dose-related variable suggesting that, for those susceptible to the effect, hypertension was manifested within the first five years of exposure.