Table 1.
Overview of included studies.
| Cohort Name | Cohort Design | N * at Risk | N * Incident PD | Mean Age, yrs ** | % Females | Duration of Follow-Up, yrs (Range) ** |
|---|---|---|---|---|---|---|
| Montréal cohort [18] | Enriched iRBD cohort | 47 | 10 | 70.7 | 27.0 | 3.5 (1.0–6.0) |
| ABC Study [19] | Population-based cohort | 2424 | 42 | 75.6 | 51.6 | 10 |
| Homburg/Saar cohort [20] | Population-based cohort | 468 | 5 | 57.5 | 53.0 | 6.7 (2.0–10.1) |
| BLSA cohort [21] | Population-based cohort | 40 | 10 | 79.4 | 20.0 | 2.6 (1.0–5.3) |
| Rotterdam Study [23] | Population-based cohort | 7386 | 57 | 65.3 | 57.4 | 8.3 (0.0–15.0) |
| NEDICES cohort [26] | Population-based cohort | 2450 | 21 | 72.8 | 57.2 | 3.4 (2.9–3.9) |
| PARS cohort [27] | Enriched cohort (hyposmia/familial) | 136 | 8 | 67.1 | 38.0 | 3.8 (1.0–5.0) |
| Multicentre iRBD [25] | Multicentre enriched iRBD cohort | 430 | 57 *** | 67.4 | 19.0 | 3.6 |
| Amsterdam study [8] | Enriched cohort (familial) | 353 | 5 | 58.8 | 56.7 | 5 |
* N is the number of individuals per group. ** The numbers presented are the median for the Rotterdam study and the means for all other studies. *** The numbers presented are in reference to all persons in the cohort converting to PD; cognitive tests were administered on a subgroup. It is expected that the numbers presented in the table resemble the actual numbers. No regression was performed, and as such, this was deemed an acceptable surrogate.