Sleep restriction progress to cardiac autonomic imbalance

Peer review under responsibility of Alexandria University Faculty of Medicine.

Available online 31 May 2017

Figures & data

Fig. 1 Effect of restricted sleep on karolinska sleepiness scale (KSS), where ^* significance change (p ≤ 0.05) compared with normal sleep and ^# – significance change (p ≤ 0.05) compared with 4th day.

Table 1 Effect of restricted sleep on body mass index (BMI), skin fold and body fat percentage, where ^* significance change (p ≤ 0.05) compared with normal sleep and ^# – significance change (p ≤ 0.05) compared with 4th day.

	1st Day	4th Day	7th day
Sleep time (h)
Normal sleep	8.5 ± 2.0	8.2 ± 1.5	8.3 ± 1.2
Restricted sleep	1.4 ± 0.9	1.3 ± 0.7	1.0 ± 0.8
BMI (kg/m^2)
Normal sleep	21.89 ± 8.24	22.52 ± 7.32	24.32 ± 5.64
Restricted sleep	22.45 ± 7.15	25.30 ± 6.56	27.83 ± 8.67
Biceps (mm)
Normal sleep	6.80 ± 0.68	6.70 ± 0.55	6.60 ± 0.47
Restricted sleep	6.65 ± 0.45	6.60 ± 0.40	6.75 ± 0.30
Triceps (mm)
Normal sleep	13.25 ± 2.40	14.23 ± 1.85	13.95 ± 1.60
Restricted sleep	13.80 ± 1.75	14.10 ± 1.50	14.50 ± 1.25
Sub-scapular (mm)
Normal sleep	12.70 ± 1.89	11.80 ± 2.10	12.25 ± 1.70
Restricted sleep	13.25 ± 1.70	12.60 ± 2.56	13.10 ± 1085
Supra-iliac (mm)
Normal sleep	15.45 ± 2.55	16.70 ± 1.40	15.20 ± 2.15
Restricted sleep	16.20 ± 1.90	15.80 ± 1.75	16.50 ± 1.80
Body fat percentage (mm)
Normal sleep	22.20 ± 3.15	23.17 ± 3.40	22.65 ± 3.20
Restricted sleep	21.80 ± 3.50	22.50 ± 3.75	23.30 ± 3.80

Table 2 Effect of restricted sleep on time and frequency domain of HRV analysis. Where ^* significance change (p ≤ 0.05) compared with normal sleep and ^# – significance change (p ≤ 0.05) compared with 4th day.

	1st Day	4th Day	7th day
Time domain
Mean NN (ms)
Normal sleep	860 ± 182	875 ± 155	858 ± 167
Restricted sleep	893 ± 118	1375 ± 210^*	2046 ± 232^*
SDNN (ms)
Normal sleep	47.12 ± 3.85	45.28 ± 4.65	44.23 ± 5.74
Restricted sleep	46.85 ± 3.20	31.42 ± 7.30^*	14.25 ± 6.53^*
RMSSD (ms)
Normal sleep	39.20 ± 3.74	37.12 ± 4.85	36.84 ± 4.96
Restricted sleep	38.73 ± 3.20	23.38 ± 6.82^*	10.30 ± 3.64^*
Frequency domain
TSP (ms^2)
Normal sleep	3628 ± 380	3462 ± 236	3610 ± 250
Restricted sleep	3570 ± 296	2767 ± 326^*	1938 ± 215^*
VLF (ms^2)
Normal sleep	873 ± 95	838 ± 60	863 ± 73
Restricted sleep	885 ± 80	1237 ± 112^*	1749 ± 130^*
LF (ms^2)
Normal sleep	1067 ± 170	1039 ± 86	1096 ± 133
Restricted sleep	1123 ± 103	1482 ± 150^*	2123 ± 245^*
HF (ms^2)
Normal sleep	955 ± 120	915 ± 110	890 ± 105
Restricted sleep	876 ± 132	623 ± 104^*	260 ± 112^*
LF (nu)
Normal sleep	42.25 ± 6.53	41.85 ± 5.20	40.96 ± 5.75
Restricted sleep	43.67 ± 4.20	57.60 ± 7.13^*	80.70 ± 8.55^*
HF (nu)
Normal sleep	38.42 ± 3.80	36.50 ± 5.29	37.30 ± 4.20
Restricted sleep	37.28 ± 4.33	25.39 ± 4.80^*	10.64 ± 5.66^*
LF/HF
Normal sleep	1.05 ± 0.26	1.10 ± 0.13	1.08 ± 0.20
Restricted sleep	1.21 ± 0.30	2.37 ± 0.45^*	4.26 ± 0.63^*

* Significance change (p ≤ 0.05) compared with normal sleep.

Fig. 2 Effect of restricted sleep on correlation between low frequency [LF(nu)and high frequency [HF(nu)] at 4th day of restricted sleep period.

Fig. 3 Effect of restricted sleep on correlation between low frequency [LF(nu)and high frequency [HF(nu)] at 7th day of restricted sleep period.