Figure 1

Associations of the comorbidity burden with age. All subjects were divided into 5 sub-groups (<50 years, 50–59 years, 60–69 years, 70–79 years and ≥80 years) by age. The comorbidity indices, including the Comorbidity Index (A), Elixhauser Comorbidity Index (B) and Charlson Cormorbidity Index (C), increased with age in both patients with PD and Parkinsonism.