Table 1.
Baseline clinical characteristics of the participants in this study
| Healthy controls | iRBD | DLB | P value | |
|---|---|---|---|---|
| n | 44 | 50 | 22 | |
| Male/female | 15/29 | 27/23 | 13/8 | 0.14 |
| Age (years) | 68.6 ± 6.3 | 70.6 ± 5.9 | 76.1 ± 5.9 | 6.37 × 10–5a |
| RBD duration (years) | – | 5.0 ± 4.7 | – | 0.47 |
| MMSE | 27.7 ± 2.1 | 27.0 ± 2.6 | 18.7 ± 5.3 | 2.62 × 10–9b |
| B-SIT | – | 6.2 ± 2.8 | – | 0.84 |
| MDS-UPDRS part I | – | 8.1 ± 5.8 | 15.8 ± 10.1 | 0.0032 |
| MDS-UPDRS part II | – | 4.1 ± 4.2 | 15.4 ± 11.3 | 1.02 × 10–5 |
| MDS-UPDRS part III | – | 7.2 ± 6.0 | 39.3 ± 18.2 | 6.67 × 10–11 |
| Hoehn & Yahr stage | – | – | 2.3 ± 0.7 | – |
| Digit span test | − 0.48 ± 0.68 | 0.11 ± 0.90 | − 0.29 ± 1.41 | 0.14 |
| TMT-A | − 0.097 ± 0.39 | − 0.32 ± 1.01 | − 1.22 ± 1.99 | 0.29 |
| CWST | − 0.21 ± 0.90 | − 0.77 ± 1.22 | − 1.45 ± 1.29 | 0.092 |
| BNT | 0.67 ± 0.45 | − 0.16 ± 1.17 | − 1.60 ± 0.89 | 1.50 × 10–6c |
| RCFT | − 0.98 ± 1.16 | − 1.44 ± 1.52 | − 2.49 ± 1.47 | 0.016d |
| SVLTi | 0.43 ± 1.02 | − 0.31 ± 0.97 | − 1.25 ± 0.86 | 2.00 × 10–4e |
| SVLTd | 0.37 ± 0.93 | − 0.62 ± 1.12 | − 1.33 ± 1.16 | 8.33 × 10–4f |
| SVLTr | 0.77 ± 0.68 | − 0.21 ± 1.14 | − 1.25 ± 1.24 | 6.93 × 10–5g |
| COWAT | − 0.083 ± 0.81 | − 0.56 ± 1.01 | − 1.07 ± 1.65 | 0.064 |
| TMT-B | 0.54 ± 0.20 | − 1.49 ± 2.47 | − 4.00 ± 2.66 | 3.12 × 10–4h |
All scores are shown as the mean ± SD. Wilcoxon’s rank-sum test was used to compare MDS-UPDRS part I, II and III between iRBD and DLB. Kruskal–Wallis test and chi-square test were used to compare age and sex distribution and clinical profiles between healthy controls, iRBD, and DLB. Post-hoc Dunn’s test was used to compare group differences as follows
aDLB vs healthy controls (P = 3.70 × 10–5), DLB vs iRBD (P = 0.0024)
bDLB vs healthy controls (P = 2.00 × 10–8), DLB vs iRBD (P = 1.84 × 10–7)
cDLB vs healthy controls (P = 6.29 × 10–6), DLB vs iRBD (P = 9.55 × 10–5)
dDLB vs healthy controls (P = 0.039), DLB vs iRBD (P = 0.032)
eDLB vs healthy controls (P = 3.37 × 10–4) and DLB vs iRBD (P = 0.0046)
fDLB vs healthy controls (P = 6.56 × 10–4) and DLB vs iRBD (P = 0.038)
gDLB vs healthy controls (P = 6.03 × 10–5), DLB vs iRBD (P = 0.0092) and healthy control vs iRBD (P = 0.033)
hDLB vs healthy controls (P = 2.34 × 10–4) and healthy control vs iRBD (P = 0.011)
RBD rapid-eye-movement sleep behavior disorder, DLB dementia with Lewy bodies, MMSE Mini-mental status exam, B-SIT Brief smell identification test, MDS-UPDRS Movement Disorders Society-Unified Parkinson Disease Rating Scale, BNT Boston Naming Test, COWAT Controlled Oral Word Association Test, CWST Korean Color Word Stroop Test, RCFT Rey Complex Figure Test copy, SVLT Seoul Verbal Learning Test, TMT Trail Making Test