Stress level and heart rate variability in police post-occurrence of bank robbery: an experience report

Abstract

Introduction: The expectation of armed confrontation is among the most stressful elements in police work. Knowledge about perceived stress and cardiovascular markers in police officers comes from simulations. However, to date, information about psychophysiological responses during high-risk occurrences is scarce. Objectives: To assess stress levels and heart rate variability in policemen before and after attending a bank robbery. Methods: Elite police officers (30.4 ± 3.7yrs) filled in a stress questionnaire and had their heart rate variability monitored at the beginning (7:00 am) and at the end (7:00 pm) of a work shift. At about 5:30 pm, these policemen were called to respond to a bank robbery in progress. Results: No significant changes in sources or symptoms of stress were found between before and after the incident. However, statistical reductions were found in heart rate range interval (R-R interval [-13.6%]), pNN50 (-40.0%), and low frequency (-28%) and the low frequency/high frequency ratio increased (200%). These results suggest that although no change in the level of perceived stress was found, a significant reduction in heart rate variability may be attributed to a reduction in activation of the parasympathetic system. Conclusions: The expectation of armed confrontation is among the most stressful occurrences in police work. Research knowledge about perceived stress and cardiovascular markers in police officers comes from simulations. Data on psychophysiological responses post-occurrence of high-risk scenarios are scarce. This research may help law enforcement organizations find means to monitor police officers’ acute stress levels after any high-risk occurrences.