Inattentive and hyperactive preschool-age boys have lower sympathetic and higher parasympathetic activity

Table 1 Subject characteristics and HRV profiles in boys and girls

	All subjects (N = 88)	Boys	Girls	p value
Male/female	41/47	41	47	0.06
Age (years)	5.61 ± 0.56	5.59 ± 0.51	5.64 ± 0.56	0.62
Gestational age (weeks)	37.90 ± 4.82	37.31 ± 6.54	38.49 ± 2.05	0.29
Birth weight (kg)	3.15 ± 0.35	3.15 ± 0.35	3.17 ± 0.38	0.79
HRV measurements
R–R intervals (ms)	616.70 ± 17.65	616.20 ± 19.44	617.20 ± 15.98	0.85
Var [ln(ms²)]	7.78 ± 0.93	7.96 ± 0.83	7.69 ± 0.99	0.39
VLF [ln(ms²)]	6.71 ± 8.54	6.77 ± 0.79	6.65 ± 0.92	0.47
LF [ln(ms²)]	6.49 ± 0.94	6.67 ± 0.88	6.40 ± 0.97	0.82
HF [ln(ms²)]	6.44 ± 1.30	6.71 ± 1.20	6.37 ± 1.35	0.53
TP [ln(ms²)]	7.79 ± 0.95	7.94 ± 0.88	7.63 ± 0.99	0.95
LF % (ν)	47.03 ± 15.84	45.54 ± 16.17	48.52 ± 15.04	0.35
LF/HF [ln(ratio)]	0.69 ± 0.74	−0.01 ± 0.75	0.14 ± 0.72	0.35

Data are presented as mean ± standard deviation
Analysis of the data was by Student’s t test (for continuous variables) and by chi-square test (for categorical variables)
HRV heart rate variability, Var variance of R–R intervals, VLF very low frequency power, LF low frequency power, HF high frequency power, TP total power, LF % normalized LF, LF/HF ratio of LF to HF

ISSN: 1880-6562