Session Information
Date: Wednesday, September 25, 2019
Session Title: Epidemiology
Session Time: 1:15pm-2:45pm
Location: Les Muses, Level 3
Objective: To estimate the number of people with Parkinson’s disease dementia (PDD) in New Zealand and how this has changed over time.
Background: People with Parkinson’s often develop dementia. Cognitive impairment and dementia represent disease stages with increased caregiver burden. Many with dementia require care in residential care facilities, the cost of which is subsidized in New Zealand, thus, PDD represents an economic cost to the state. Having a robust method to estimate the number of people with PDD would help in the planning for healthcare and support services for people with PDD and Parkinson’s in general.
Method: A hierarchical Bayesian survival model that, given a Parkinson’s diagnosis, estimated the probability of PDD by age and sex was developed from a convenience sample of 328 people with Parkinson’s. This cohort has been followed longitudinally with detailed cognitive assessments for up to 10 years, resulting in over 1000 assessments and 95 people classified as having dementia. Using pharmaco-epidemiological methods calibrated through known diagnoses, we have previously determined the number of people with Parkinson’s disease in New Zealand by age and sex from 2006 to 2017. By then multiplying each age-sex group count by the matching PDD probability we were able to estimate the number of people with PDD in New Zealand.
Results: We estimated the number of people with PDD in New Zealand to have increased from 2360 (95% uncertainty interval [1800, 2760]) in 2006 to 3400 [2570, 3970] in 2017. This indicates that the prevalence of dementia within the Parkinson’s population is 32% [25%, 36%]. The mean age of those with PDD was 83 years.
Conclusion: This is the first nationwide estimate of the number of people in New Zealand living with PDD. We have previously predicted a doubling of the number of people with Parkinson’s in New Zealand by 2040, thus, we expect the number of people with PDD to concomitantly increase in the coming decades.
To cite this abstract in AMA style:
T. Pitcher, D. Myall, J. Dalrymple-Alford, M. Macaskill, T. Anderson. Number of people with Parkinson’s dementia in New Zealand [abstract]. Mov Disord. 2019; 34 (suppl 2). https://www.mdsabstracts.org/abstract/number-of-people-with-parkinsons-dementia-in-new-zealand/. Accessed June 14, 2025.« Back to 2019 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/number-of-people-with-parkinsons-dementia-in-new-zealand/