TABLE 2.

Associations between cfDNA biomarkers and risk of developing MSA and PD in logistic regression models.

Plasma measures	PD						MSA
	Crude model			Multivariate model			Crude model			Multivariate model
	OR	95% CI	P-value	OR	95% CI	P-value	OR	95% CI	P-value	OR	95% CI	P-value
cf-nDNA level
Per SD	0.73	0.50–1.05	0.102	0.74	0.42–1.20	0.247	0.65	0.38–1.03	0.094	1.39	0.68–2.74	0.340
Q1	ref			ref			ref			ref
Q2	1.55	0.68–3.55	0.298	1.56	0.51–4.93	0.437	1.13	0.43–2.95	0.808	2.03	0.40–1.16	0.401
Q3	0.58	0.24–1.34	0.202	0.65	0.20–2.04	0.463	0.34	0.11–1.00	0.058	3.06	0.50–2.34	0.243
P-value for trend			0.162			0.422			0.046			0.252
cf-mtDNA copy number
Per SD	1.06	0.75–1.49	0.742	1.21	0.75–1.92	0.427	1.04	0.68– 1.56	0.851	0.97	0.50–1.91	0.937
Q1	ref			ref			ref			ref
Q2	1.19	0.52–2.71	0.676	1.69	0.54–5.48	0.372	1.47	0.54–4.06	0.449	1.15	0.16–7.67	0.885
Q3	0.77	0.33–1.75	0.527	0.76	0.23–2.48	0.651	0.96	0.34–2.72	0.943	1.06	0.18–6.22	0.945
P-value for trend			0.458			0.462			0.831			0.987
cf-mtDNA deletion level
Per SD	1.04	0.74–1.47	0.823	1.02	0.64–1.61	0.943	1.11	0.73–1.69	0.619	1.31	0.66–2.69	0.447
Q1	ref			ref			ref			ref
Q2	1.31	0.57–3.01	0.527	0.98	0.33–2.93	0.975	1.73	0.65–4.79	0.278	1.56	0.30–8.36	0.594
Q3	0.83	0.36–1.93	0.670	0.78	0.24–2.45	0.672	0.87	0.30–2.49	0.789	1.26	0.25–6.51	0.781
P-value for trend			0.714			0.689			0.945			0.748

Bold values: P-value < 0.05. Crude model: unadjusted model; Multivariate model: adjusted for age, sex, BMI, education level, hypertension, coronary heart disease, and cerebrovascular disease in PD patients; adjusted for age, sex, BMI, education level, smoking status, and cerebrovascular disease in MSA patients; Trend analysis utilized the median value of each tertile. cf-mtDNA, circulating cell-free mitochondrial DNA; cf-nDNA, circulating cell-free nuclear DNA; PD, Parkinson’s disease; MSA, multiple system atrophy; OR, odds ratio; CI, confidence interval; SD, standard deviation; -, not available.