Exercise test and 24-hour heart rate recording in men with high and low casual blood pressure levels.

Abstract

A population survey in a mixed suburban-rural community included a casual blood pressure recording. From a total of 780 men not under treatment for hypertension those with blood pressures above the 95th centile between the ages of 20 and 59 yr were selected (group A). Age-matched controls were selected among those with blood pressures below the 30th centile (group B). There were 31 subjects in each group. Those in group A weighed significantly more than those in group B, and their obesity index was significantly higher. There were no significant differences between the groups in radiological heart volume, physical working capacity or vital capacity. The heart rate during exercise was significantly higher in group A than in group B. The same difference in heart rate between the 2 groups was seen in the recumbent position before as well as after rest in the clinic. Interestingly, no differences in heart rate between the 2 groups could be shown outside the clinic on a continuous 24 h ECG. This may indicate that the group with the higher blood pressures were hyperreactive when exposed to the mental stress of being examined at the clinic. The differences in blood pressure between the groups persisted at a repeated casual blood pressure measurement 3 yr after the initial examination and similar differences in blood pressure were also found after rest and during exercise.