Evaluation of the Age Dependence of Conventional and Novel Photoplethysmography Parameters

Artery Research

Table 2 Results of correlation analysis of PPG parameters and age

PPG parameters	Correlation values of PPG parameters with age		Results of GAM analysis of the relationship between age and PPG parameters
PPG parameters	Pearson's r	p	Deviance explained	EDOF	p
Conventional PPG parameters
ET(PPG)	0.589	< .001	0.4000	5.6458	< .001
Crest Time	0.570	< .001	0.5092	12.4659	< .001
LVETi	0.539	< .001	0.2944	2.5483	< .001
AGEi	0.485	< .001	0.2385	2.5483	< .001
SysAlpha	-0.418	< .001	0.1834	2.5483	< .001
d/a	-0.376	< .001	0.1540	2.5483	< .001
b/a	0.207	0.025	0.0487	2.5483	0.052
Si	0.181	0.050	0.0708	2.7463	0.099
Ri	-0.159	0.085	0.0635	2.8567	0.010
Novel PPG parameters
eLVET1*	0.548	< .001	0.3574	5.6458	< .001
DNi*	-0.517	< .001	0.2693	2.5483	< .001
eLVET2*	0.450	< .001	0.2063	2.5483	< .001
c-d incidence*	0.419	< .001	0.2459	5.6458	< .001
PPG Score parameters
Heart Fitness Score*	-0.493	< .001	0.3310	3.3728	< .001
CV Health Score*	-0.450	< .001	0.2253	2.7463	< .001
Total Score*	-0.301	< .001	0.1815	3.3728	< .001

EDOF effective degrees of freedom, ET(PPG) left ventricular ejection time measured by PPG, LVETi left ventricular ejection time index, AGEi ageing-index, SysAlpha systolic slope inclination, d/a and b/a ratios of the different inflection points of the second derivative of the pulse wave, Si stiffness index, Ri reflection index, eLVET1* and eLVET2* the early left ventricular ejection time 1 and 2 are the two-time components of "Crest Time”, DNi* dicrotic notch index, c-d incidence* c-d point detection ratio, Score parameters scores were calculated based on the 30 + parameters derived from the proprietary analysis of the 2 min pulse-wave recording
^*These parameters are developed by our research group. Most of them are not yet validated in clinical studies
For more information on GAM and an explanation of its measured values, see the Additional file1.docx
For a more detailed description of the PPG parameters, see Table 1

ISSN: 1876-4401