Supplementary Material for: Parkinson's Disease Case Ascertainment in the EPIC Cohort: The NeuroEPIC4PD Study

<strong><em>Background/Aims:</em></strong> Large epidemiological prospective studies represent an important opportunity for investigating risk factors for rare diseases such as Parkinson's disease (PD). Here we describe the procedures we used for ascertaining PD cases in the EPIC (European Prospective Investigation into Cancer and Nutrition) study. <b><i>Methods:</i></b> The following three-phase procedure was used: (1) elaboration of a NeuroEPIC4PD template for clinical data collection, (2) identification of all potential PD cases via record linkage and (3) validation of the diagnosis through clinical record revision, in a population of 220,494 subjects recruited in 7 European countries. All cases were labelled with the NeuroEPIC4PD diagnoses of ‘definite', ‘very likely', ‘probable', or ‘possible' PD. <b><i>Results:</i></b> A total of 881 PD cases were identified, with over 2,741,780 person-years of follow-up (199 definite, 275 very likely, 146 probable, and 261 possible). Of these, 734 were incident cases. The mean age at diagnosis was 67.9 years (SD 9.2) and 458 patients (52.0%) were men. Bradykinesia was the most frequent presenting motor sign (76.5%). Tremor-dominant and akinetic rigid forms of PD were the most common types of PD. A total of 289 patients (32.8%) were dead at the time of the last follow-up. <b><i>Conclusions:</i></b> This exercise proved that it is feasible to ascertain PD in large population-based cohort studies and offers a potential framework to be replicated in similar studies.

背景与目的：大型前瞻性流行病学研究为探究帕金森病（Parkinson's disease, PD）这类罕见疾病的风险因素提供了重要契机。本研究针对欧洲癌症与营养前瞻性调查（European Prospective Investigation into Cancer and Nutrition, EPIC）队列中帕金森病病例的确认流程进行详述。
方法：本研究采用如下三阶段流程：（1）研制用于临床数据采集的NeuroEPIC4PD模板；（2）通过记录链接识别所有潜在帕金森病病例；（3）针对在7个欧洲国家招募的220494名研究对象，通过临床病历复核完成诊断验证。所有病例均按照NeuroEPIC4PD诊断标准被划分为“确诊”“极可能”“很可能”“可能”帕金森病四个等级。
结果：本研究共确认881例帕金森病病例，累计随访人年数超过2741780，其中确诊199例、极可能275例、很可能146例、可能261例。其中734例为新发病例。患者确诊时的平均年龄为67.9岁（标准差9.2），男性患者共458例，占比52.0%。运动迟缓是最常见的首发运动症状（占比76.5%）。震颤主导型与运动不能强直型帕金森病为最常见的临床亚型。末次随访时，共有289例患者（占比32.8%）死亡。
结论：本次研究证实，在大型人群队列研究中确认帕金森病病例具有可行性，并可为同类研究提供可复制的标准化流程框架。