Blood Pressure in Night Shift Workers: Orcadian Rhythms and Levels and Their Seasonal Differences

摘要

The average diurnal blood pressure profiles (DBPPs) were studied in subjects working at different hours of the day, including nighttime. The DBPPs and the curve levels in winter and in summer were compared. The study material included more than 497 000 prework blood pressure (BP) measurement points in 30 566 locomotive drivers. It was found that the average DBPP of the subjects working at different hours of the day is of a markedly nondipper type; i.e., despite night wakefulness, the BP was lower at night but not as low as that of those sleeping at night. In the cohort studied, the shapes of the DBPP curve did not differ in winter and in summer; however, the BP levels in winter were significantly higher.