Heterogeneity of Parkinson's disease in the early clinical stages using a data driven approach

Objective: To investigate the heterogeneity of idiopathic Parkinson's disease (PD) in a data driven among a cohort of patients in the early clinical stages of the disease meeting established criteria. Methods: Data on demographic, motor, mood, and cognitive measures were collected from consecutive patients in the early stages of PD (Hoehn and Yahr I-III) attending a specialist PD clinic. Statistical cluster analysis of the data allowed the existence of the patient subgroups generated to explored. Results: The analysis revealed four main subgroups: (a) patients with a younger disease onset; (b) a dominant subgroup of patients; (c) a non-tremor dominant subgroup with significant levels of - impairment and mild depression; and (c a subgroup with rapid disease progression but no impairment. Conclusions: This study complements and extends previous research by using a data driven define the clinical heterogeneity of early PD. The approach adopted in this study for the subgroups of patients within Parkinson's disease has important implications for generating hypotheses on defining the heterogeneity of this common condition and its aetiopathological basis thus its treatment.