Table 1.
Clinical and imaging characteristics of the 21 RBD subjects
| PDRP z score category | DAT scan category | RBD subject | PDRP z score | Lowest putamen DAT‐binding ratio | Total olfaction score (TDI)b | Sex | Age | RBD duration (years) | Age at onset RBD | MoCA | UPDRS‐III |
|---|---|---|---|---|---|---|---|---|---|---|---|
| <1.8 | Normal | 1 | 1.7 | 2.0c | 33.8 | Male | 57.4 | 5.0 | 52.4 | 30.0 | 4.0 |
| 2 | 1.0 | 2.3 | 33.5 | Female | 58.9 | 7.0 | 51.9 | 27.0 | 0.0 | ||
| 3 | ‐0.3 | 2.5 | 33.5 | Female | 68.3 | 6.0 | 62.3 | 23.0 | 2.0 | ||
| 4 | 1.1 | 2.5 | 29.5 | Male | 54.0 | 6.0 | 48.0 | 26.0 | 4.0 | ||
| 5 | 0.9 | 2.4 | 28.0 | Male | 56.4 | 6.0 | 50.4 | 27.0 | 1.0 | ||
| 6 | 0.2 | 2.2 | 19.5 | Male | 67.1 | 25.0 | 42.1 | 28.0 | 0.0 | ||
| 7 | 0.4 | 2.9 | 0.0 | Male | 56.0 | 9.0 | 47.0 | 25.0 | 1.0 | ||
| Abnormal | 8 | 0.3 | 1.2 | 19.0 | Male | 65.9 | 12.0 | 53.9 | 26.0 | 2.0 | |
| 9 | 1.1 | 1.0 | 13.0 | Male | 66.4 | 6.0 | 60.4 | 27.0 | 3.0 | ||
| ≥1.8 | Normal | 10 | 2.2 | 2.5 | 29.0 | Male | 57.8 | 5.0 | 52.8 | 28.0 | 1.0 |
| 11a | 2.2 | 2.3 | 23.5 | Male | 62.6 | 14.0 | 48.6 | 24.0 | 5.0 | ||
| 12 | 3.0 | 2.5 | 20.5 | Male | 57.5 | 2.5 | 55.0 | 27.0 | 6.0 | ||
| 13 | 1.9 | 2.3 | 16.5 | Male | 64.5 | 2.0 | 62.5 | 26.0 | 2.0 | ||
| 14a | 2.5 | 2.0c | 15.5 | Female | 70.1 | 3.0 | 67.1 | 28.0 | 4.0 | ||
| Abnormal | 15 | 2.2 | 1.7 | 27.5 | Male | 64.0 | 14.0 | 50.0 | 28.0 | 4.0 | |
| 16 | 1.8 | 1.6 | 25.8 | Male | 66.9 | 3.0 | 63.9 | 27.0 | 2.0 | ||
| 17 | 3.4 | 0.9 | 17.0 | Male | 61.5 | 4.0 | 57.5 | 27.0 | 0.0 | ||
| 18 | 3.1 | 1.7 | 13.0 | Male | 65.4 | 6.0 | 59.4 | 27.0 | 6.0 | ||
| 19 | 4.2 | 2.0c | 2.0 | Male | 49.9 | 4.0 | 45.9 | 24.0 | 1.0 | ||
| 20 | 5.7 | 1.2 | 0.0 | Male | 63.2 | 4.0 | 59.2 | 28.0 | 1.0 | ||
| 21 | 1.9 | 1.8 | 0.0 | Male | 66.6 | 2.0 | 64.6 | 22.0 | 5.0 |
In these 2 RBD subjects, 18F‐FDG‐PET was performed respectively 3.4 and 1.5 months before DAT‐SPECT.
bOlfaction was measured with the Sniffin' Sticks test; total TDI scores are reported in this table (see main text). A TDI > 30 indicates normal olfactory function; a TDI ≤ 20 indicates severe hyposmia. A TDI score < 18 was previously associated with an increased risk of phenoconversion to PD/DLB.16
cSubjects 1, 14, and 19 all have putamen DAT‐binding ratios of 2.0. Subjects 1 and 14 are still in the “normal DAT” category, and subject 19 is in the “abnormal DAT” category. This is because DAT‐binding ratios were considered abnormal if they were 2 standard deviations below the value expected for age. For subjects 1 and 14, the ratio of 2.0 is still normal for age (57 and 70 years old, respectively); however, for subject 19, this ratio is abnormal for age (50 years old). We note that subject 1 has a borderline‐normal DAT‐binding ratio and PDRP z‐score (z = 1.7).
RBD, idiopathic REM sleep behavior disorder; PDRP, Parkinson's disease‐related pattern; DAT, dopamine transporter; MoCA, Montreal Cognitive Assessment; UPDRS‐III, part 3 of the Unified Parkinson's Disease Rating Scale (2003 version).