Previous estimates of the incidence of Parkinson’s disease have varied for reasons that are not completely understood but may be attributable to the location of the study, small sample sizes, or how cases were defined. Accurate estimates are needed to inform care planning and help identify risks for Parkinson’s.
To this end, researchers used data from Kaiser Permanente Northern California (KPNC), the Honolulu-Asia Aging Study (HAAS), the Rochester Epidemiology Project (REP), US Medicare, and Ontario health administrative databases to estimate the incidence of Parkinson’s disease in 2012. The study population included 6.7 million person-years of data in patients 45 and older.
Estimates of the incidence of Parkinson’s disease in patients 65 and older ranged from 108 to 212 per 100,000 and from 47 to 77 per 100,000 in patients 45 and older. Incidence rates increased with age in each of the five study cohorts for patients aged 65 to 84 and were higher for males than females in the study cohorts where sex-based comparisons could be made (Medicare, Ontario, and KPNC). Geographical patterns were also identified, with a higher incidence of Parkinson’s in certain areas such as southern California and central Pennsylvania.
Based on these data, researchers estimate the incidence of Parkinson’s to be 60,000 to 95,000 cases per year among adults ages 45 and older compared to previously reported estimates of 40,000-60,000 new cases per year and propose a working estimate of 62 per 100,000 person-years, or 86,000 cases per year.
“The growth in those diagnosed and living with PD underscores the need for policy makers to confront an increasing strain on clinical services as well as the need to provide additional funding for research that can lead to improved therapies if not an outright cure.”