TABLE 4.
Comparisons of cfDNA biomarkers between PD and MSA subgroups.
| Plasma measures | PD | P-value | MSA | P-value | ||
| Without cognitive impairment (n = 37) | With cognitive impairment (n = 25) | Without cognitive impairment (n = 18) | With cognitive impairment (n = 15) | |||
| cf-nDNA level | 7.985 ± 2.743 | 9.095 ± 3.221 | 0.123 | 6.852 ± 2.933 | 9.403 ± 4.272 | 0.008 |
| cf-mtDNA copy number | 13.072 ± 10.826 | 12.462 ± 14.426 | 0.472 | 13.530 ± 10.380 | 11.448 ± 7.303 | 0.925 |
| cf-mtDNA deletion level | 1.077 ± 0.064 | 1.071 ± 0.041 | 0.576 | 1.062 ± 0.077 | 1.101 ± 0.067 | 0.226 |
|
Without depression (n = 32) |
With depression (n = 30) |
Without depression (n = 19) |
With depression (n = 14) |
|||
| cf-nDNA level | 7.901 ± 3.053 | 9.000 ± 2.820 | 0.061 | 7.972 ± 4.448 | 8.064 ± 2.757 | 0.392 |
| cf-mtDNA copy number | 12.756 ± 11.066 | 12.900 ± 13.675 | 0.606 | 11.431 ± 9.927 | 14.147 ± 7.748 | 0.294 |
| cf-mtDNA deletion level | 1.079 ± 0.048 | 1.069 ± 0.063 | 0.638 | 1.078 ± 0.072 | 1.081 ± 0.080 | 0.975 |
| Without anxiety (n = 27) | With anxiety (n = 35) | Without anxiety (n = 11) | With anxiety (n = 22) | |||
| cf-nDNA level | 7.557 ± 2.286 | 9.108 ± 3.280 | 0.065 | 8.564 ± 5.662 | 7.735 ± 2.483 | 0.291 |
| cf-mtDNA copy number | 14.280 ± 11.832 | 11.704 ± 12.694 | 0.375 | 13.570 ± 12.863 | 12.090 ± 6.702 | 0.810 |
| cf-mtDNA deletion level | 1.076 ± 0.058 | 1.073 ± 0.054 | 0.986 | 1.062 ± 0.069 | 1.088 ± 0.077 | 0.549 |
| Without RBD (n = 34) | With RBD (n = 28) | Without RBD (n = 5) | With RBD (n = 28) | |||
| cf-nDNA level | 8.506 ± 3.054 | 8.344 ± 2.920 | 0.779 | 7.335 ± 2.609 | 8.132 ± 3.968 | 0.874 |
| cf-mtDNA copy number | 13.861 ± 11.342 | 11.569 ± 13.463 | 0.351 | 11.243 ± 8.107 | 12.823 ± 9.310 | 0.940 |
| cf-mtDNA deletion level | 1.069 ± 0.060 | 1.081 ± 0.049 | 0.631 | 1.067 ± 0.061 | 1.082 ± 0.077 | 0.513 |
| Without constipation (n = 21) | With constipation (n = 40) | Without constipation (n = 5) | With constipation (n = 28) | |||
| cf-nDNA level | 7.803 ± 2.943 | 8.749 ± 3.006 | 0.362 | 7.727 ± 2.905 | 8.062 ± 3.948 | 0.746 |
| cf-mtDNA copy number | 17.097 ± 11.896 | 10.717 ± 12.195 | 0.049 | 18.947 ± 6.522 | 11.447 ± 9.037 | 0.076 |
| cf-mtDNA deletion level | 1.086 ± 0.065 | 1.069 ± 0.050 | 0.292 | 1.070 ± 0.033 | 1.081 ± 0.080 | 0.948 |
| Without olfaction loss (n = 29) | With olfaction loss (n = 33) | Without olfaction loss (n = 28) | With olfaction loss (n = 5) | |||
| cf-nDNA level | 8.367 ± 3.242 | 8.491 ± 2.760 | 0.821 | 7.797 ± 3.877 | 9.214 ± 3.192 | 0.408 |
| cf-mtDNA copy number | 12.879 ± 12.558 | 12.779 ± 12.252 | 0.726 | 12.926 ± 9.511 | 10.667 ± 6.119 | 0.804 |
| cf-mtDNA deletion level | 1.073 ± 0.053 | 1.076 ± 0.058 | 0.508 | 1.084 ± 0.077 | 1.058 ± 0.055 | 0.642 |
Bold values: P-value < 0.05 after adjusted for age, sex, BMI and education years. Data are expressed as the mean ± SD. Definition of abnormal: for cognitive impairment, a cut-off of 26 on the MMSE score; for depression, a cut-off of 8 on the HAMD score; for anxiety, a cut-off of 7 on the HAMA score; for RBD, a cut-off of 19 on the RBDQ-HK score; for olfactory loss, a cut-off of 22 on the AHRS score; constipation was screened by the part 21 of NMSS. RBD, rapid eye movement sleep behavior disorder; cf-mtDNA, circulating cell-free mitochondrial DNA; cf-nDNA, circulating cell-free nuclear DNA; PD, Parkinson’s disease; MSA, multiple system atrophy.