Effects of shift work on 24-hour ambulatory blood pressure and its variability among Japanese workers

Scand J Work Environ Health. 2000 Oct;26(5):421-6. doi: 10.5271/sjweh.563.


Objectives: This study examined the effects of rotating shift work on blood pressure in a comparison of ambulatory blood pressure and long-term changes in blood pressure between shift and day workers.

Methods: Ambulatory blood pressure was measured for 24-hour periods at an interval of 30 minutes for 27 shift workers and 26 day workers when they worked during the day. Blood pressure was compared between these 2 groups of workers for 4 time categories (awake, sleep, nonwork awake, and work periods). Their long-term blood pressures, recorded in annual surveys, were reviewed for long-term changes. These comparisons were adjusted for the effects of body mass index, alcohol intake, anger expression, and physical activity.

Results: On the average, sleep time was shorter and the anger-in (ie, anger suppressed) score was higher for the shift workers than for the day workers, but body mass index and alcohol intake did not differ between the 2 groups. Even after adjustment for these co-variables, the mean systolic blood pressure during the 24-hour, awake, and work periods were higher among the shift workers than among the day workers. The 24-hour standard deviations of the systolic blood pressures were also higher for the shift workers than for the day workers. Among the shift workers, but not among the day workers, a significant long-term increase was observed in systolic blood pressure measured in the annual surveys.

Conclusions: These results suggest that shift work may increase systolic blood pressure levels among Japanese men.

Publication types

  • Comparative Study

MeSH terms

  • Adult
  • Age Factors
  • Alcohol Drinking
  • Analysis of Variance
  • Anger
  • Blood Pressure Monitoring, Ambulatory
  • Blood Pressure* / physiology
  • Body Mass Index
  • Circadian Rhythm
  • Data Interpretation, Statistical
  • Humans
  • Japan
  • Male
  • Middle Aged
  • Sex Factors
  • Sleep / physiology
  • Work Schedule Tolerance* / physiology
  • Work Schedule Tolerance* / psychology