ABSTRACT
Various factors such as occupational and environmental risk factors affect blood pressure. Nowadays, shift work is a common work schedule. Studies on effect of shift work on hypertension showed different results. We studied the effect of shift work on hypertension and pre-hypertension among workers in a rubber manufacturing company. In a cross-sectional study, 265 workers studied. Workers divided to shift workers and day workers, their systolic and diastolic blood pressure [SBP and DBP] were measured by standard method. Then mean systolic and diastolic blood pressure and prevalence of hypertension and pre-hypertension were compared between two groups. Logistic regression analysis was used to evaluate the correlation between hypertension and shift work. Chi square, t-test and logistic regression were used for statistical analysis. There were no statistically significant differences between groups in the variables of age, BMI, employment duration, smoking and other confounding factors [p>0.05]. The mean values of SBP and DBP and prevalence of pre-hypertension and hypertension was significantly more in shift workers than day workers [p<0.05]. After logistic regression analysis with adjustment of confounding variables, significant correlation between shift work and hypertension was found [p<0.05]. Odds ratio for hypertension in shift workers was 2.86. Our results suggested that shift work can be a risk factor for hypertension and pre-hypertension. Therefore more attention should be paid to shift workers by periodic measurement of blood pressure