Residents with 24-hour on-call shifts had higher heart rates (84 vs. 79 bpm) and stress index (12.1 vs. 9.96) with reduced HRV (RMSSD 27 vs. 34.5) vs. those without on-call duties.
Do 24-hour on-call shifts reduce heart rate variability and increase physiological stress in medical residents?
Medical residents working 24-hour on-call shifts demonstrate reduced heart rate variability and increased sympathetic activity, indicating greater physiological stress independent of physical activity levels.
Absolute Event Rate: 0% vs 0%
Abstract Background/Introduction Heart rate variability (HRV) is a critical indicator of autonomic nervous system function and overall cardiovascular health. Residents frequently experience high workloads, particularly those with on-call duties, which may impact their HRV. However, the role of on-call shifts in altering HRV parameters remains insufficiently explored. Purpose This study aims to compare HRV parameters between medical residents with 24-hour on-call shifts and those without, while also assessing potential confounding factors such as physical activity levels. Methods A total of 140 volunteer residents from two tertiary care centers were included in the study, with 104 having regular on-call duties and 36 not participating in on-call shifts. HRV parameters were assessed using standard time-domain and frequency-domain measures, including heart rate, RMSSD, SDNN, SNS, PNS, stress index, and Poincaré plot analysis. The International Physical Activity Questionnaire (IPAQ) was used to evaluate physical activity levels. Comparisons between groups were conducted using appropriate statistical tests. Results Residents with on-call shifts exhibited significantly higher heart rates (84 vs. 79 bpm, p=0.006) and stress index (12.1 vs. 9.96, p=0.003). Additionally, HRV markers of parasympathetic activity, including RMSSD (27 vs. 34.5, p=0.002) and PNS (-1.42 vs. -0.86, p=0.002), were significantly lower in the on-call group, suggesting increased sympathetic dominance. Similarly, SDNN (38.8 vs. 47.2, p=0.006), Poincaré SD1 (19.3 vs. 24.4, p=0.002), and SD2 (51.6 vs. 61.4, p=0.012) were reduced in the on-call group. No significant differences were observed in IPAQ scores between groups (p0.05). Conclusion(s) Residents with on-call duties exhibit reduced HRV and increased sympathetic activity compared to their counterparts without night shifts, suggesting greater physiological stress. The absence of significant differences in physical activity levels indicates that workload-related stress, rather than lifestyle factors, may drive these autonomic changes. Further discussion should be held on the impact this stress has on the health of young physicians, as a chronic risk factor such as diabetes and hypertension and potentially should be considered in compensation and retirement calculation.Heart rate variability parameters Demographic and secondary parameters
Kılıç et al. (Sat,) reported a other. Residents with 24-hour on-call shifts had higher heart rates (84 vs. 79 bpm) and stress index (12.1 vs. 9.96) with reduced HRV (RMSSD 27 vs. 34.5) vs. those without on-call duties.