Parkinson’s disease Prevalence Study

New Parkinson’s disease prevalence study

Trying to estimate the number of people living with Parkinson’s disease (PD) in North America is extremely important but notoriously difficult. It is critical to know the prevalence of PD because it informs lawmakers who make decisions concerning allocation of research funds about the true impact of the disease, and it also informs public health officials who need to plan for the growing PD population. The difficulties in ascertaining this number however, lie in trying to capture every case of a highly varied disease, on a continent without a centralized medical system and without uniformity in medical care.

A newly published study on the prevalence of PD is the most comprehensive study yet to tackle this question. The study was conducted with the support of Parkinson’s Foundation and consisted of five separate studies to determine the local prevalence — one each in Minnesota, Hawaii, and Ontario, Canada, and two in California. The data from each study was then analyzed together and compared to US Medicare data. According to this strategy, the estimated prevalence of PD in people 45 and older is 572 per 100,000. Using the last available US Census Bureau data from 2010, the overall prevalence of PD across North America in 2010 was calculated to be 680,000.  Population projections were then used to extrapolate the prevalence for the year 2020, calculated to be 930,000, and for the year 2030, calculated to be 1,238,000.

As indicated in the paper, these numbers likely underestimate the true prevalence of PD for a number of reasons. In most of the studies, the ascertainment of cases relied on the use of an electronic medical record or insurance claims data. Therefore, people who did not seek care for their symptoms were not captured. In addition, if the diagnostic codes entered into these systems were incomplete or inaccurate, additional cases of PD would not be captured. Therefore, the prevalence data presented in this study needs to be considered a minimum estimate.

Obtaining data that is as accurate as possible regarding the prevalence of PD in North America will continue to be an active area of research and concern for the PD community, especially as our aging population grows and the potential for PD diagnosis increases.