Blood pressure variations during a working day at age 28: effects of different types of work and blood pressure level at age 18.

During an ordinary work day blood pressure was self-monitored once every hour in two samples of asymptomatic nonmedicating 28-year-old men. They were selected on the basis of previous compulsory blood pressure recordings made at the age of 18 when they had been drafted for military service. Subjects in the "original hypertensive sample" with "strain" occupations (hectic and uncontrollable, such as waiter, driver and cook) had more marked elevations of systolic blood pressure during work hours than other subjects.