Abstract

Background: Insufficient sleep has been shown to be associated with increased cardiovascular morbidity and overall mortality. Sleep deprivation can affect the cardiovascular autonomic control leading to sympathovagal imbalance.

Aims and Objectives: This study was conceptualized to evaluate the effect of sleep deprivation on heart rate recovery (HRR) after treadmill exercise test in otherwise healthy adult subjects.

Materials and Methods: The study included 50 healthy young adults in the age group of 18–35 years. The study subjects were divided into two groups of 25 each. Group 1 included subjects doing daytime duty. Group 2 included subjects who had completed their night shift duty. A maximal symptom-limited exercise stress test was performed by each subject in both the groups. The HRR was calculated as the reduction in HR from peak exercise to the 30th s (HRR 30), 1st min (HRR 1), 2nd min (HRR 2), 3rd min (HRR 3), and 5th min (HRR 5).

Results: Subjects with sleep deprivation achieved a significantly lower level of the maximum HR at the peak of exercise stress test than the subjects with normal sleep (P < 0.05). HRR at 30 s (HRR 30 s) and 1 min (HRR 1) was found to be significantly lower in sleep-deprived subjects as compared to subjects taking normal sleep (P < 0.01).

Conclusion: HRR after 1 min of exercise stress testing was significantly affected by sleep deprivation. This is explained by the effect of sleep deprivation on the cardiovascular autonomic control.

Key words: Heart Rate Recovery; Parasympathetic; Sleep Deprivation; Stress Test