[Effect of environmental stress on blood pressure during the work shift]

To evaluate blood pressure (BP) and heart rate (HR) behavior in individuals during the working journey in two environments with different work stressors.

The study comprised 46 male individuals working in a wood processing factory in Botucatu, Brazil. Twenty seven (27.4+/-5.4 yrs, mean+/-SD) worked in the production line performing intense physical activity (G1) at high room temperatures and noise levels. Nineteen (33.2+/-7.6 yrs old) performed managerial tasks mostly comfortably seated at low noise, air-conditioned offices (G2). After anthropometric measurements (obesity, total and local adiposity) and blood biochemistry analyses (glucose, triglycerides and cholesterol), their BP and HR were registered during three consecutive days at 3 different time of the day: in the beginning, in the middle and at the end of the working journey.

There were similar BP and HR changes during the journey for G1 and G2, but G1 showed higher rates. Due to the wide variability of BP responses within each group, participants were divided in two subgroups: responders (GR1 and GR2) with BP increase >10%, and non-responders (GN1 and GN2). Both subgroups showed similar anthropometric and biochemical patterns differing only in their BP response and, in the case of GR1,family history for hypertension. GR1 showed higher BP and HR than GR2.

Individual changes of BP and HR responses to environmental stressors during the working journey indicates that these factors should be considered while evaluating BP measurements and might be considered as potential factors for hypertension.