The effects of acut sleep deprivation on cardiovascular autonomic control and stress markers

Background and Aim: The aim of this study was to investigate the effects of 24 hours of sleep deprivation on cardiac autonomic control and cardiac stress markers in healthy young adult women. Methods: Before the study, sleep was assessed with the Pittsburgh Sleep Quality Index, and cardiac health by examination, electrocardiography, and echocardiography. The first 15 volunteers considered suitable in terms of sleep and cardiac health performed a 14-minute submaximal aerobic exercise on a cycle ergometer in the morning following a normal night's sleep and again after a night of total sleep deprivation. The exercise protocol consisted of an incremental workload of 15 Watts per minute for the first 11 minutes, followed by 3 minutes of unloaded pedaling. Autonomic nervous system function was assessed using the heart rate recovery index and heart rate variability. The heart rate recovery index was calculated as the difference between peak heart rate during exercise and heart rate at 30 seconds and 1, 2, 3, 4, 5 minutes of recovery. Serum samples obtained from venous blood before and after exercise were analyzed for N-terminal pro–B-type natriuretic peptide and galectin-3 levels using the ELISA method, and high sensitivity cardiac troponin I levels using the immunoassay method. Statistical analyses of percentage changes in heart rate variability, blood biomarkers, and heart rate recovery between pre- and post-exercise measurements under normal sleep and sleep-deprived conditions were performed using paired-sample t-tests for normally distributed data and Wilcoxon signed-rank tests for non-normally distributed data. A p-value <0,05 was considered statistically significant. Results: After one night of sleep deprivation, the post-exercise reduction in standart deviation of normal RR intervals and the number of successive RR intervals that differ by more than 50 ms was smaller than after normal sleep (p=0.04, p=0.02), while galectin-3 levels increased more (p=0.003). Heart rate recovery, high sensitivity cardiac troponin I, and N-terminal pro-B-type natriuretic peptide were unaffected. Conclusion: Twenty-four hours of sleep deprivation may reduce post-exercise cardiac parasympathetic activity and elevate galectin-3 levels, indicating a heightened inflammatory response in healthy young women. Keywords: Galectin-3, heart rate recovery, heart rate variability, N-terminal-pro-B-type natriuretic peptide, submaximal exercise. Financial Support: This study was supported by the Scientific Research Projects Unit of Trakya University. Project No: 2025/10.