While several studies have investigated the clinical progression of cognitive decline in Parkinson's disease (PD) patients, there has been a paucity of data on specifically evaluating PD patients with a disease duration of over 20 years. This study retrospectively investigated the frequency of dementia in PD (PDD) patients with a disease duration of over 20 years assessed in research clinics across the UK and Australia. Data from 2327 PD patients meeting the United Kingdom Parkinson's Disease Society Brain Bank Criteria was pooled. A diagnosis of probable PDD was made according to the Movement Disorder Society Level 1 criteria. Thirty-six participants had a disease duration of at least 20 years. Of the 36 patients, only 7 (19%) were classified as probable PDD. Compared to PD patients without dementia, those with dementia had lower levels of educational attainment and exhibited more severe motor features. Additionally, 34 out of the 36 patients (94%) exhibited a non-tremor dominant phenotype. No significant differences in age, age onset, disease duration, dopaminergic medication use, and sex distribution were observed between PD patients with and without dementia. Findings from the present study suggest that the prevalence of dementia in long-term PD patients may be lower than anticipated and suggest that the trajectory of cognitive decline in PD patients can be different. These findings highlight the need to investigate factors that might affect the outcome of cognitive decline in long-term PD patients, which may lead to the determination of potential modulating factors in the development of dementia in these patients.

中文翻译：

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长期帕金森氏病患者的痴呆：一项多中心回顾性研究。

尽管有几项研究调查了帕金森氏病（PD）患者认知能力下降的临床进展，但缺乏专门评估病程超过20年的PD患者的数据。这项研究回顾了在英国和澳大利亚的研究诊所中评估的，病程超过20年的PD（PDD）患者痴呆的发生率。汇总了2327名符合英国帕金森氏病学会脑库标准的PD患者的数据。根据运动障碍学会1级标准诊断可能的PDD。三十六名参与者的病程至少为20年。在这36名患者中，只有7名（19％）被归类为可能的PDD。与没有痴呆的PD患者相比，痴呆症患者的教育程度较低，运动功能较严重。此外，在36名患者中，有34名（94％）表现出非震颤显性表型。在患有和没有痴呆的PD患者之间，未观察到年龄，发病年龄，疾病持续时间，多巴胺能药物的使用以及性别分布的显着差异。从本研究中发现，长期PD患者的痴呆症患病率可能低于预期，并提示PD患者认知能力下降的轨迹可能不同。这些发现强调需要研究可能影响长期PD患者认知下降结果的因素，这可能导致确定这些患者痴呆发展中潜在的调节因素。