Ambulatory blood pressure monitoring among emergency medical services night shift workers

OBJECTIVES: Higher 24-hour blood pressure (BP) and blunted BP dipping during sleep and night-time hours are associated with adverse health outcomes. Night shift work may affect 24-hour BP and dipping patterns, but empirical data in emergency medical services (EMS) clinician shift workers are sparse. We implemented ambulatory blood pressure monitoring (ABPM) in EMS workers to characterise BP during night shift work versus a non-workday, and sleep versus wake. METHODS: Participants worked night shifts. Hourly ABPM and wrist actigraphy (to measure sleep) were collected during two 24-hour periods, one scheduled night shift and one non-workday. Blunted BP dipping was defined as a BP decrease of <10%. RESULTS: Of 56 participants, 53 (53.6% female, mean age 26.5 (SD 7.5) years) completed the study. During daytime sleep on a workday, 49.1% of participants had blunted systolic BP (SBP) or diastolic BP (DBP) dipping. During night-time sleep on a non-workday, 25% had blunted SBP dipping and 3.9% blunted DBP dipping. Blunted SBP or DBP dipping occurred among all participants who did not nap during the night shift or who napped <60 min. Blunted SBP dipping occurred in only 14.3% of participants who napped 60-120 min. CONCLUSIONS: During night shift work, the BP dipping of EMS shift workers is blunted; however, most who nap for 60 min or longer experience a healthy dip in BP. The potential health consequences of these observations in EMS clinicians warrant further study.