Objective: To define the nomenclature for Early Onset Parkinson Disease (EOPD) / Young Onset Parkinson Disease (YOPD), and the age at onset (AAO) cut off defining this condition.
Background: EOPD/YOPD is defined as PD with AAO after age 21 years but before the usual AAO for PD. Consensus is lacking and the reported maximal age for EOPD/YOPD has varied from 40 to 60 years, leading to lack of uniformity in published studies, difficulty in scientific harmonization of data, and, consequently, difficulty in identifying the specific challenges and unmet needs of this patient population. EOPD and YOPD have both been used in the literature, somewhat interchangeably.
Method: An extensive review of the literature in addition to Task Force meetings were conducted. A consensus on the nomenclature and upper age cut off for the AAO was reached.
Results: 1-Literature has seen a shift from the use of YOPD towards EOPD since the mid-2000’s. This seems motivated by an attempt to avoid age-related stigmatization of patients. 2- In defining EOPD, and reviewing literature by country, 38% of the countries use 40 or 45 years as a cut off, 56% of the countries use 50 or 51 years as cut off, and 6% use 55 or 60 years. 3- The vast majority of international genetic studies in PD use an age cut off of less than 50 years to define EOPD. 4- Many studies suggest that changes in the estrogen level can affect the predisposition to develop PD, making the average age at menopause of 50 years a potentially important factor to consider when defining EOPD. 5- Considering the differential impact of the AAO of PD on professional and social life, using 50 years as the upper cut off for the definition of EOPD seems reasonable.
Conclusion: This task force recommends the use of EOPD rather than YOPD. It defines EOPD as PD with AAO after 21 years but before 50 years. We anticipate that this will help harmonize future research on the specific challenges and unmet needs of this subset of PD patients, as well as guide future research and other initiatives.
To cite this abstract in AMA style:
R. Mehanna, K. Smilowska, A. Merola, B. Zhang, B. Post, C. Marras, J. Fleisher, K. Kumar, M. Salari, O. Ross, R. Alcalay, T. Hatano, V. Mcconvey, Y-R. Wu, E-K. Tan, R. Savica. Defining nomenclature and age cut off for Early Onset Parkinson’s Disease: Recommendations from the Early Onset Parkinson’s Disease Task Force. [abstract]. Mov Disord. 2022; 37 (suppl 2). https://www.mdsabstracts.org/abstract/defining-nomenclature-and-age-cut-off-for-early-onset-parkinsons-disease-recommendations-from-the-early-onset-parkinsons-disease-task-force/. Accessed May 19, 2025.« Back to 2022 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/defining-nomenclature-and-age-cut-off-for-early-onset-parkinsons-disease-recommendations-from-the-early-onset-parkinsons-disease-task-force/