Modifications of Cardiac Autonomic Profile Associated With a Shift Schedule of Work

Abstract

Continuous weekly changes of time of maximum and minimum in the cardiac sympathetic and vagal autonomic control may play a role in the excessive rate of cardiovascular diseases in shift workers. The reduced values of the indexes of cardiac sympathetic modulation during night work might be related to the presence of sleepiness or diminished alertness, which in turn could facilitate errors and accidents.

Heart rate variability and endothelial function after sleep deprivation and recovery sleep among male shift and non-shift workers

“…The current findings thus support the idea of increased cardiovascular risk among shift workers. Previous studies have shown that normalized LF power or LF/HF is higher on night duty than when off duty and asleep at night (44)(45)(46)(47)(48)(49) and is higher on days including a night shift compared to days including a morning shift (50). Normalized LF power or LF/HF has also been shown to be higher among shift compared to non-shift workers when both groups work day shifts (51,52) or are asleep at home (53).…”

Shift work and cardiovascular disease – pathways from circadian stress to morbidity

“…Over 15 studies using field measures have reported lower levels of parasympathetic modulation of heart rate variability or increased sympathetic activity in shift work (for example 68,[80][81][82][83][84]. Others have reported that nighttime work is associated with reduced cardiac sympathetic modulation (81). Shift work may predispose individuals also to prolongation of QT intervals corrected for heart rate (QTc) (85), indicating a possible pro-arrhythmic potential of shift work.…”

Circadian rhythm of blood pressure is transformed from a dipper to a non-dipper pattern in shift workers with hypertension

“…17 Some studies have demonstrated that shift work is associated with increased cardiovascular morbidity and mortality. [18][19][20] Recently, Furlan et al 21 reported that a shift schedule of work might be associated with modification of the cardiac autonomic profile. Although the reason is not known, high BP leading to increased sympathetic nervous activity due to sleep disturbance 22,23 may be partly responsible.…”