Blood glucose variability impacts heart rate dynamics in older type 2 diabetic and coronary heart disease patients

Table 5 Correlation analysis between blood glucose fluctuation parameters and heart rate variability time domain indicators

Heart rate variability time domain indicator	MAGE		MODD		LAGE		MPPGE
	r value	P value	r value	P value	r value	P value	r value	P value
SDNN	-0.231	0.033	-0.198	0.042	-0.224	0.035	-0.291	0.000
SDANN	-0.218	0.036	-0.196	0.044	-0.269	0.024	-0.295	0.000
SDNNindex	-0.259	0.029	-0.195	0.045	-0.302	0.000	-0.289	0.000
rMSSD	-0.263	0.026	-0.206	0.040	-0.189	0.047	-0.214	0.036
pNN50	-0.201	0.039	-0.213	0.037	-0.254	0.021	-0.239	0.034

MAGE: Mean amplitude of glycemic excursions; MODD: Mean of daily differences; LAGE: Largest amplitude of glycemic excursions; MPPGE: Mean postprandial glucose excursions; SDNN: Standard deviation of normal-to-normal interval; SDANN: Standard deviation of the average normal-to-normal interval; SDNNindex: Standard deviation of normal-to-normal intervals over every 5-minute period; rMSSD: Root mean square of successive differences; pNN50: Percentage of normal-to-normal intervals differing by > 50 ms.