Phd in CLINICAL EXPERIMENTAL NEUROSCIENCE AND PSYCHIATRY

Thesis title: AGE AT ONSET INFLUENCES ON EARLY-STAGE SYMPTOMS PROGRESSION IN PARKINSON’S DISEASE

Abstract The intricate relationship between age at onset, underlying pathophysiology, and disease progression in Parkinson's disease (PD) has yet to be fully elucidated, particularly during the early stages of the illness. In our retrospective study, we aimed to explore the clinical presentation and progression of both motor and non-motor symptoms, as well as complications associated with treatment within the first five years following disease onset among individuals stratified by age. We classified 131 participants into "Early-Onset PD" (EOPD; onset before 50 years), "Middle-Onset PD" (MOPD; onset between 50-69 years), and "Late-Onset PD" (LOPD; onset after 70 years) groups. The T0 visit coincided with the clinical diagnosis, while the T1 visit occurred five years (±5 months) later. At T0, the groups exhibited no significant disparities in motor characteristics. However, by T1, LOPD patients displayed a markedly higher occurrence of gait dysfunction and postural instability. Moreover, LOPD participants demonstrated a significantly elevated prevalence of non-motor symptoms, particularly within the cardiovascular, cognitive, and neuropsychiatric spheres. Our research underscores a notably divergent progression of motor and non-motor symptoms during the early phase of PD, contingent upon age at onset. These insights help clarify the role of age at onset in disease progression, inform the design of tailored pharmacological and non-pharmacological approaches for PD management, and implement specialised rehabilitation strategies. Keywords: age at onset; motor symptoms; non-motor symptoms; Late-Onset PD; Middle-Onset PD; Early-Onset PD; Parkinson's disease.