Sleep patterns and physiological markers of stress in graduate paramedics

\({Introduction / Aims}\) New graduates are entering the paramedic workforce in Victoria in unprecedented numbers, undertaking shift work patterns that are known to be a risk factor for a raft of major medical conditions. Whilst most research in the healthcare field examines hospital-based staff, limited research is available that examines new recruits within the emergency medical response field and how they adapt to shift work. This study has assessed graduate paramedics during the initial five months of rotational shift work, aiming to identify if the quality and quantity of sleep is altered during this period of rotational shift work and if early risk factors of cardiovascular disease and metabolic disorders manifest during this initial exposure to shift work. \({Methods}\) Graduate paramedics commencing employment with Ambulance Victoria were assessed over a 25-day block before starting shift work (Baseline), and during their 1st and 5th month of shift work. In each block, sleep and activity level was recorded 24-hours a day using a wrist-worn actigraph device. Subjects also maintained a sleep log each morning and completed regular subjective sleep questionnaires. From this, Sleep duration - the number of hours/minutes scored as ‘asleep’ - was established. Sleep Efficiency was calculated as a percentage of time spent asleep from the time spent in bed. The number of awakenings (NoA) and the Wake After Sleep Onset (WASO) for each sleep period were recorded as an indication of sleep quality. Total sleep time (TST) for the 25-day period was also tallied and recorded in hours and minutes for each assessment. Data was compared across each assessment period using the 25-day average, during shift work and during RDOs. Further assessments of general health and well-being, including height, weight, waist circumference, resting heart rate, blood pressure, fasting blood glucose, body composition, aerobic fitness (step test), and subjective stress questionnaires were also conducted at the commencement of the Baseline period, at the conclusion of shift work Month 1, and pre- and post- shift work Month 5. \({Results}\) 28 participants (13 male and 15 female) completed the full study protocol. A significant (p =0.046) increase in the total sleep time was observed across the 25-days of each month when shift work was undertaken. The number of sleep episodes recorded during these months of shift work also increased (p <0.005), however sleep efficiency did not differ significantly (p =0.17). The NoA recorded for the sleep episode after night duty was significantly less in Month 1 (p <0.005) and Month 5 (p <0.01) compared to Baseline. All sleep metrics recorded during RDOs were not different to Baseline with the exception of the night before returning to work, where there was a significant reduction in sleep duration (p <0.005). During shift work, self-reported poor sleep quality increased compared to Baseline (p