RESUMEN
The aim of the study is to evaluate if "outdoor" workers exposed to chemical, physical and psycho-social urban stressors could have alterations of systolic and diastolic blood pressure at rest and heart disease investigated by electrocardiogram compared with a group of "indoor" workers not exposed. Among non-smoking, the mean values of systolic blood pressure at rest were significantly higher in exposed compared to non exposed (p = 0.002) and frequency of electrocardiographic abnormalities was significantly higher in exposed (20.8%) than not exposed (10.4%, p = 0.02). Among exposed, the values of systolic blood pressure at rest were significantly higher in smokers than non-smokers (p = 0.002). Among non-exposed, the frequency of electrocardiographic abnormalities was significantly higher in smokers than non-smokers (p = 0.002). The study results suggest that chronic exposure to chemical, physical and psycho-social stressors can be a cardiovascular risk factor in addition to cigarette smoking in a manner determined by the categories of outdoor workers.