Table 2.
A list of the evidence supporting and refuting the following variable as a risk factor of freezing of gait
| Supporting evidencea | Refuting evidencea | |
|---|---|---|
| Demographic risk factors | ||
| Male sex | [16, 17, 25] | [18–24, 26] |
| Low education level | [22] | [19, 23, 24] |
| Onset age | [16, 17, 20–23, 25, 26] | |
| Age | [18, 19, 21–25] | |
| Baseline longer disease duration | [20, 23] | [16–19, 21]b |
| Motor symptoms | ||
| Gait disorders | [16–21, 23] | [22] |
| Motor phenotype | [16, 17, 21, 22] | [18, 19, 25] |
| Motor fluctuation | [21] | [23] |
| Balance, festination and falls | Festination and falls [23], balance [20] | Balance [19] |
| Non-motor symptoms | ||
| Cognitive disturbance | [16, 17, 22–24] | [18–21] |
| Depression | [19, 20, 22] | [16, 23, 24] |
| Anxiety | [18] | [16, 23, 24] |
| Sleep | Insomnia [22], daytime sleepiness [24] | RBD [16, 18, 24], daytime sleepiness [16, 23] |
| Others | Speech problems [20], hallucination [23] | |
| Neuroimaging and fluid parameters | ||
| Lower striatal DAT update | [16, 17, 25] | |
| White matter hyperintensities | [26] | |
| CSF Aβ42 | [16] | |
| Medication use | ||
| High LEDD | [21] | [18, 19, 23, 26] |
| Dopamine agonist | [22] | |
Demographic information, motor symptoms, non-motor symptoms, neuroimaging, fluid parameters, and medication use were all included
DAT Dopamine transporter, CSF Cerebrospinal fluid, LEDD Levodopa equivalent daily doses
aOnly the prospective studies that followed early-stage PD patients over time and the retrospective studies that clearly recorded the clinical manifestation prior to FOG onset were cited here
bBaseline disease duration instead of the whole disease duration was analyzed in those cited studies. Relatively short disease duration might be the reason for failure to identify disease duration as a risk factor