Category: Parkinson's Disease: Cognitive functions
Objective: To investigate whether progression to dementia in senile Parkinson’s disease, SPD, (disease onset after 70 years) differs from that in old Parkinson’s disease, OPD, (over 70 years but with onset at 40-70 years).
Background: Dementia frequency in Parkinson disease (PD) increases with age. Older age at disease onset and disease duration are independently associated with PD dementia [1]. Cortical Lewy pathology – major correlate of dementia – usually progresses slowly but may progress rapidly in SPD [2].
Method: We examined the clinical records of PD patients over 70 years, seen in 2019 at the outpatient clinics of our PD Institute, dividing them into SPD and OPD according to age at PD onset, and assessing the frequency of mental decay (MMSE <26/30).
Results: Of 2072 cases over 70 years, 915 (44%) were SPD and 1157 (56%) OPD. MMSE was administered to 94 (10%) SPD and 149 (13%) OPD (p=0.067). Forty-nine SPD (52%) and 56 OPD (37.5%) (p=0.026) had age and education-adjusted MMSE score <26, suggesting mental decay. SPD and OPD patients with mental decay differed, as expected, for age at disease onset (p<0.001) and disease duration (p<0.001), but also differed for age at examination (p<0.001) with SPD older than OPD. However the two groups did not differ for years of education, MMSE and UPDRS scores, or Hoehn and Yahr stage.
Conclusion: Our data are preliminary and retrospective in nature. Nevertheless they indicate that frequency of cognitive impairment is higher in SPD than OPD, particularly since, although SPD were older than OPD, MMSE scores were adjusted for age and education. This suggests that dementia pathogenesis may differ between the two groups, although comorbidities, lifestyles, and intrinsic factors (like chronic aminergic denervation or interaction between Parkinson and Alzheimer lesions [3]) must all be taken into account when interpreting the results.
References: [1] Cilia et al 2015. J Neurol Neurosurg Psychiatry;86:849-855 [2] Halliday and McCann 2010. N.Y. Acad. Sci;1184:188–195 [3] Irwin et al 2012. Ann Neurol;72:587-598
To cite this abstract in AMA style:
P. Soliveri, F. Del Sorbo, A. Zecchinelli, G. Sacilotto, N. Meucci, M. Zini, C. Mariani, S. Tesei, G. Pezzoli. Does age at onset of Parkinson’s disease affect the development of dementia? [abstract]. Mov Disord. 2020; 35 (suppl 1). https://www.mdsabstracts.org/abstract/does-age-at-onset-of-parkinsons-disease-affect-the-development-of-dementia/. Accessed May 13, 2025.« Back to MDS Virtual Congress 2020
MDS Abstracts - https://www.mdsabstracts.org/abstract/does-age-at-onset-of-parkinsons-disease-affect-the-development-of-dementia/