Table 1.
The basic characteristics of included studies of meta-analysis
| Author | Year | Country | Study design | N(case) | PD (case) | M (%) | Age | Mets (%) | BMI | Follow-up |
|---|---|---|---|---|---|---|---|---|---|---|
| Katri | 2015 | Finland | retrospective | 6,641 | 89 | 54.6 | mean: 56.5 | 17.1 | mean: 26.2 | 30-year |
| Penga | 2018 | China | retrospective | NA | 255 | 58 | mean: 67.7 | 32.2 | mean: 25.8 | 5-year |
| Pengb | 2018 | China | retrospective | NA | 105 | 58.1 | mean: 68.5 | 35.2 | mean: 25.9 | 5-year |
| Dallaha | 2020 | Korea | retrospective | 6,098,405 | 20,895 | 100 | mean: 54.6 | 26.9 | mean:23.9 | 6.4-year |
| Dallahb | 2020 | Korea | retrospective | 6,098,405 | 20,895 | 0 | mean: 54.5 | 27.8 | mean:23.4 | 6.4-year |
| Jeong | 2021 | Korea | retrospective | 903,063 | NA | 53.81 | mean: 55.47 | NA | mean:24.08 | 5-year |
| Sanga | 2021 | Korea | retrospective | 5,522,813 | 20,524 | 55.40 | mean: 55.7 | NA | mean:24.8 | 7-year |
| Sangb | 2021 | Korea | retrospective | 5,522,814 | 20,524 | 54 | mean: 55.3 | NA | mean:24.5 | 7-year |
| Sangc | 2021 | Korea | retrospective | 5,522,815 | 20,524 | 48.4 | mean: 58.7 | NA | mean:25.9 | 7-year |
| Ga | 2018 | Korea | retrospective | 17,163,560 | 44,205 | 47.9 | mean: 58.1 | 34.1 | mean:25.6 | 5.3-year |
| Roh | 2020 | Korea | retrospective | 314,737 | 819 | 56.1 | NA | 27.2 | NA | 7.23-year |
Abbreviations: NA: not available; N: number; PD: Parkinson’s disease; Mets: Metabolic syndrome