Table 3.
Prodromal neurodegenerative signs among sleep maintenance vs sleep onset insomnia subtypes.
| Onset Insomnia (n = 2,051) |
Maintenance Insomnia (n = 4,333) |
Onset vs Ctrl | Maintenance vs Ctrl | Onset vs Maintenance | |
|---|---|---|---|---|---|
| n (%) or Mean ± SD | ORAge&Sex(+Education)_Adjusted [95% CI] | ||||
| Motor signs | |||||
| Balance task | |||||
| Best performance (seconds) | 36.6 ± 23.7 | 40.3 ± 23.0 | - | - | - |
| <15th percentile | 330 (17.4) | 592 (14.4) | 1.33 [1.16, 1.52] | 1.05 [0.94, 1.16] | 1.28 [1.09, 1.50] |
| Timed-Up-and-Go | |||||
| Total time | 9.90 ± 3.64 | 9.50 ± 2.66 | - | - | - |
| <15th percentile | 378 (18.8) | 576 (13.5) | 1.52 [1.34, 1.73] | 0.98 [0.89, 1.09] | 1.55 [1.33, 1.80] |
| 4-m walk task | 4.34 ± 1.17 | 4.26 ± 1.17 | 1.13 [1.08, 1.17] | 1.01 [0.98, 1.04] | 1.11 [1.06, 1.17] |
| Sit-to-stand | |||||
| Average time/trial | 2.79 ± 1.06 | 2.63 ± 072 | 1.21 [1.14, 1.28] | 0.95 [0.91, 1.00] | 1.27 [1.18, 1.36] |
| Neuropsychiatric signs | |||||
| F-A-S verbal fluency task | |||||
| Total score | 38.4 ± 12.9 | 39.8 ± 12.8 | - | - | - |
| <15th percentile | 364 (18.3) | 630 (15.0) | 1.15 [1.01, 1.30] | 0.97 [0.88, 1.07] | 1.18 [1.01, 1.37] |
| Recall task | |||||
| Immediate recall | 5.83 ± 1.94 | 5.95 ± 1.88 | - | - | - |
| <15th percentile | 496 (25.0) | 918 (21.9) | 1.127 [1.004, 1.264] | 0.96 [0.88, 1.04] | 1.19 [1.04, 1.37] |
| Delayed recall | 4.06 ± 2.18 | 4.14 ± 2.15 | - | - | - |
| <15th percentile | 461 (23.2) | 897 (21.4) | 1.07 [0.95, 1.20] | 0.93 [0.86, 1.02] | 1.17 [1.02, 1.35] |
| Miami prospective memory task | |||||
| Time-based score | 8.63 ± 0.98 | 8.69 ± 0.88 | 0.95 [0.91, 1.00] | 1.01 [0.97, 1.05] | 0.94 [0.89, 1.00] |
| Event-based score | 8.37 ± 1.50 | 8.48 ± 1.32 | 0.96 [0.93, 0.99] | 1.01 [0.98, 1.04] | 0.95 [0.91, 0.99] |
| Accuracy | 11.1 ± 1.8 | 11.3 ± 1.6 | 0.96 [0.94, 0.99] | 1.00 [0.98, 1.02] | 0.96 [0.93, 0.99] |
| <15th percentile | 359 (17.8) | 614 (14.4) | 1.24 [1.09, 1.40] | 0.98 [0.88, 1.07] | 1.27 [1.09, 1.47] |
| Psychomotor speed task and task switching | |||||
| Stroop interference error | 0.77 ± 1.98 | 0.63 ± 1.96 | - | - | - |
| >85th percentile | 578 (28.73) | 1,050 (24.59) | 1.13 [1.01, 1.25] | 0.95 [0.88, 1.03] | 1.19 [1.05, 1.35] |
| Mental alternation task | 25.83 ± 8.9 | 27.16 ± 8.35 | - | - | - |
| <15th percentile | 367 (18.82) | 561 (13.55) | 1.16 [1.02, 1.32] | 0.86 [0.78, 0.95] | 1.38 [1.18, 1.60] |
| Choice reaction task | |||||
| Accuracy | 98.72 ± 3.28 | 98.97 ± 2.93 | - | - | - |
| <15th percentile | 595 (29.4) | 1,056 (24.71) | 1.19 [1.07, 1.32] | 0.94 [0.87, 1.02] | 1.27 [1.13, 1.44] |
| Nonmotor signs | |||||
| Autonomic abnormality | |||||
| Heart-rate variability | 27.6 ± 24.0 | 29.7 ± 30.5 | - | - | - |
| <15th percentile | 340 (17.1) | 605 (14.3) | 1.20 [1.06, 1.36] | 0.98 [0.89, 1.08] | 1.24 [1.07, 1.43] |
CI = confidence interval, Ctrl = control, F-A-S = verbal fluency task, OR = odds ratio, SD = standard deviation.