P126 LONG WORKING HOURS ARE ASSOCIATED WITH INCREASED BLOOD PRESSURE VARIABILITY

Abstract

Background and Objectives: Elevated blood pressure variability (BPV) is associated with an increased risk of cardiovascular morbidity and mortality, independently of blood pressure values. Long working hours increase the risk of hypertension and cardiovascular diseases. The present study aims to determine whether long working hours have a detrimental effect on BPV. Methods: The present study relied on a prospective cohort of 3 639 white-collar workers in Quebec City evaluated at three visits: at recruitment, 3 years, and 5 years. At each visit, participants wore an ambulatory blood pressure monitor during working hours and answered a questionnaire. Work hours per week were divided into the following categories: 21 to 34 hours, 35 to 40 hours (reference group), and 41 hours or more. Working hours BPV was calculated using average real variability. Results: A total of 7 056 observations (n = 4 234 in women and n = 2 822 in men) were available. Systolic and diastolic BPV were higher in participants working long hours (41 hours and more per week) than in participants working 35 to 40 hours per week. These associations were robust to adjustment for socio-demographics, lifestyle-related and clinical risk factors as well as psychosocial stressors at work (psychological demand – job control and reward). Conclusions: Participants exposed to long working hours showed higher BPV than non-exposed participants. Intervention aiming at reducing long working hours should be considered for the primordial prevention of hypertension and cardiovascular diseases. Average real variability of systolic and diastolic blood pressure during working hours according to hours worked per week