S-23-2: CLINICAL SIGNIFICANCE OF WORK STRESS INDUCED INCREASE IN BLOOD PRESSURE IN HYPERTENSION MANAGEMENT

Abstract

We usually spend about one third time of a day for working. So it is critically important for our health if the working condition is comfortable or stressful. In many developed countries including Japan, retirement age tended to be delayed due to several reasons. This means that we must spend more time for work in our life. Elderly people are vulnerable to brain and heart diseases. So the establishment of less stressful work condition and risk management is increasingly important to prevent work-related cardiovascular events or Karoshi. Among 203 Karoshi cases received worker compensation in Japan, 60 % died of stroke while remaining cardiovascular diseases. For occupational factor, long working has been considered as a risk of Karoshi. Meta-analysis has also shown that long working hours are associated with increased risk of cardiovascular diseases, especially for stroke. In Karoshi cases, most prevalent risk factor was hypertension (40%). However, the review of literature has shown that the relationship between long working hours and blood pressure increase or hypertension is inconsistent. Interestingly, some data showed that long working hours are associated with lower risk of hypertension, suggesting that the relationship between working long hours and blood pressure increase is confounded by other factors like qualitative work stress. Karoshi unexpectedly occur. Therefore in a real world, we need to obtain an individual information on blood pressure response during work to adequately manage work-related hypertension. Ambulatory blood pressure monitoring is an ideal method to monitor blood pressure behavior during work but is not practical to perform repeatedly with short duration. Self-measurement of blood pressure may replace ambulatory monitoring to examine work-related blood pressure variation. We studied 207 treated hypertensive subjects working for 29 Rosai hospitals. Blood pressures and heart rate were measured by themselves with an automated device at standardized conditions 4 times a day: after waking, 10:00 h, 16:00 h, and before sleep on three days (Monday, Friday, and Saturday or Sunday). We could observe clear daily and weekly variation of rate pressure product (systolic blood pressure × heart rate). The increase in rate pressure product on Monday morning was significantly correlated with urinary albumin excretion and job strain index in women. Our data showed the feasibility of self-monitoring of blood pressure and heart rate at workplace. This method would be useful to monitor work-stress related hypertension in several overwork situation.