Several phenotypic differences observed in Parkinson’s disease (PD) patients have been linked to age at onset (AAO). We endeavoured to find out whether these differences are due to the ageing process itself by using a combined dataset of idiopathic PD (n = 430) and healthy controls (HC; n = 556) excluding carriers of known PD-linked genetic mutations in both groups. We found several significant effects of AAO on motor and non-motor symptoms in PD, but when comparing the effects of age on these symptoms with HC (using age at assessment, AAA), only positive associations of AAA with burden of motor symptoms and cognitive impairment were significantly different between PD vs HC. Furthermore, we explored a potential effect of polygenic risk score (PRS) on clinical phenotype and identified a significant inverse correlation of AAO and PRS in PD. No significant association between PRS and severity of clinical symptoms was found. We conclude that the observed non-motor phenotypic differences in PD based on AAO are largely driven by the ageing process itself and not by a specific profile of neurodegeneration linked to AAO in the idiopathic PD patients.

在帕金森病 (PD) 患者中观察到的几种表型差异与发病年龄 (AAO) 相关。我们试图通过使用特发性 PD ( n  = 430) 和健康对照 (HC; n = 556)，不包括两组中已知 PD 相关基因突变的携带者。我们发现 AAO 对 PD 的运动和非运动症状有几个显着影响，但是当比较年龄对这些症状与 HC 的影响时（使用评估年龄，AAA），只有 AAA 与运动症状和认知负担的正相关PD与HC之间的损伤显着不同。此外，我们探讨了多基因风险评分 (PRS) 对临床表型的潜在影响，并确定了 AAO 和 PRS 在 PD 中的显着负相关。未发现 PRS 与临床症状严重程度之间存在显着关联。