Table 4.

Partial correlations between heart rate and heart rate variablility parameters and Edinburgh Cognitive and Behavioral ALS Screen total and cognitive domain scores in patients with amyotrophic lateral sclerosis with impaired cognition

Heart rate and heart rate variablility parameters	Total ECAS score		Language domain score		Fluency domain score		Executive function domain score		Memory domain score		Visuospatial function domain score
	r	P value	r	P value	r	P value	r	P value	r	P value	r	P value
Mean HR	− 0.044	0.803	0.050	0.778	− 0.243	0.166	0.024	0.893	0.101	0.571	0.102	0.565
RRI (ms)	− 0.059	0.742	0.026	0.884	0.163	0.356	− 0.094	0.595	− 0.228	0.194	−  0.114	0.519
24-h (time domain)
SDNN (ms)	− 0.159	0.370	0.024	0.895	0.032	0.856	− 0.222	0.207	− 0.097	0.586	− 0.200	0.256
SDANN (ms)	− 0.052	0.770	− 0.018	0.917	0.069	0.700	− 0.138	0.437	0.042	0.814	− 0.162	0.359
SDNN-Index (ms)	− 0.280	0.109	0.068	0.700	− 0.051	0.777	− 0.305	0.079	− 0.223	0.205	− 0.215	0.222
RMSSD (ms)	− 0.443	0.009*	− 0.006	0.971	− 0.250	0.154	− 0.412	0.015*	− 0.199	0.259	− 0.271	0.121
pNN50 (%)	− 0.252	0.150	0.061	0.733	− 0.128	0.472	− 0.109	0.538	− 0.289	0.098	− 0.231	0.190
24-h (frequency domain)
TP (ms2)	− 0.090	0.613	0.069	0.699	0.012	0.947	− 0.073	0.682	− 0.161	0.363	− 0.063	0.722
VLF power (ms2)	− 0.036	0.839	0.121	0.494	− 0.007	0.970	− 0.005	0.978	− 0.145	0.412	− 0.034	0.847
LF power (ms2)	− 0.288	0.098	0.035	0.844	0.033	0.854	− 0.293	0.093	− 0.328	0.058	− 0.193	0.274
HF power (ms2)	− 0.252	0.151	− 0.047	0.793	0.026	0.882	− 0.173	0.329	− 0.274	0.117	− 0.281	0.107
LFnu	0.127	0.475	0.041	0.816	0.012	0.948	0.063	0.724	0.063	0.723	0.340	0.049*
HFnu	− 0.078	0.660	− 0.072	0.684	0.093	0.600	− 0.038	0.830	− 0.081	0.650	− 0.338	0.051
LF/HF	0.067	0.706	0.159	0.369	− 0.118	0.506	0.027	0.881	0.064	0.721	0.314	0.070

ALS Amyotrophic lateral sclerosis, ECAS Edinburgh Cognitive and Behavioral ALS Screen, HF power high-frequency power, LF/HF ratio of LF power to HF power, LFnu LF power in normalized units, LF power low-frequency power, pNN50 percentage difference between adjacent NN intervals > 50 ms, r partial correlation coefficient, RMSSD square root of mean sum-of-squares of differences between adjacent NN intervals, RRI RR-interval, SDANN standard deviation of average NN intervals in all 5-min segments, SDNN standard deviation of all normal-to-normal (NN) intervals, SDNN Index mean standard deviations of all NN intervals for each 5-min segment in a 24-h HRV recording, TP total power, VLF power very low-frequency power

*Statistically significant difference at P value < 0.05. Adjustments were made for age, gender, and educational level