Skip to main content
Open Access Publications from the University of California

Elevated blood pressure, decreased heart rate variability and incomplete blood pressure recovery after a 12-hour night shift work.

  • Author(s): Su, Ta-Chen
  • Lin, Lian-Yu
  • Baker, Dean
  • Schnall, Peter L
  • Chen, Ming-Fong
  • Hwang, Wen-Chang
  • Chen, Chen-Fang
  • Wang, Jung-Der
  • et al.

Shift work has been associated with increased risk of cardiovascular disease. This study was designed to determine the hemodynamic effects of 12-hour (12-h) shifts, and changes in blood pressure (BP) and heart rate variability (HRV) during 36 h rest time following 12-h shifts. Fifteen male shift workers with a mean age of 32.9 yr were recruited from a semiconductor factory. Ambulatory BP (AmBP) monitoring was performed for a total of 48 h for each participant. Six workers were monitored for 48 h by Holter electrocardiogram on both the day and night shifts. Paired self-comparison was used to estimate the difference between two hourly measurements of 12-h BP, HR, and HRV using the same timetable intra-individually. We also applied mixed models to estimate the effects of 12-h shifts on the delayed recovery of BP and heart rate (HR) in six workers who completed 96-h AmBP monitoring, including a 48-h night shift-rest period and another day shift period. Results showed that 12-h night shift work gave a persistently elevated systolic and diastolic BP (SBP and DBP) and HR, and decreased HRV compared to 12-h day shift work with the corresponding resting time. In addition, there was delayed SBP and DBP recovery on the first 12-h rest time in night shift workers, which was further demonstrated on the second 12-h rest time after adjustment for possible confounders through mixed models. In conclusion, 12-h night shift work may elevate BP and HR and decrease HRV. It is also associated with delayed BP recovery.

Many UC-authored scholarly publications are freely available on this site because of the UC Academic Senate's Open Access Policy. Let us know how this access is important for you.

Main Content
Current View