Objective: This study examined the effects of exposure to job strain on independent predictors of cardiovascular disease (ambulatory blood pressure, heart rate, and heart rate variability).
Methods: The participants comprised a homogeneous group of 159 healthy female nurses [mean age 35.9 (SD 8.5) years]. The choice of this population minimized variance attributable to gender, socioeconomic status, and work characteristics. Job demands, decision latitude, and social support were measured with the Karasek job content questionnaire, which was administered twice with an average interval of 12.2 months. The nurses' scores for job demands and decision latitude on both occasions were used to define their job-strain category. Ambulatory blood pressure, heart rate, and heart rate variability were assessed on a workday and a day of leisure.
Results: No effect on the ambulatory levels of blood pressure, heart rate, or heart rate variability was found for job strain by itself or in interaction with social support. In addition, job strain was not associated with differences in short-term or long-term physiological recovery during sleep after a workday or a day of leisure. High job demand was associated with higher systolic blood pressure at work and with higher diastolic blood pressure at work, but the latter association was found only when decision latitude was concurrently high, rather than low.
Conclusions: High job strain among young female nurses is not associated with an unfavorable ambulatory cardiovascular profile. The robust effect of job strain on male health appears to be less apparent for women.