Cosmos Study

Most Parkinson’s Diagnoses Occur After Age 70, with a Slight Rise in Diagnosis Age Since 2017

August 6, 2026

Team A:Kersten Bartelt, RNNicholas Volker

Team B:Blaine Franklin, PT, DPTEric Barkley

Key Findings

Among patients newly diagnosed with Parkinson’s disease, 90.2% were aged 60 or older at diagnosis, with a median diagnosis age of 73. Diagnoses before age 50 were rare, accounting for 2.6% of patients.
The median age at diagnosis has risen slightly, holding at 73 from 2017 through 2023 before reaching 74 in 2024 and 2025.
Median diagnosis age varied by race and ethnicity: Hispanic patients were diagnosed youngest (median 71) and White patients oldest (median 74).

Parkinson’s disease is a progressive disorder of the nervous system that affects movement, causing symptoms such as tremor, stiffness, and slowed movement that worsen over time.¹ It is most commonly diagnosed in older adults, though a smaller share of cases, sometimes called young-onset Parkinson’s, occurs in people under 50.² In recent years, some conditions long associated with older age, like cancers, have shown rising incidence among younger adults, raising questions about whether the age profile of other age-related disease is also shifting.³Because age is the strongest known risk factor for Parkinson’s,⁴ understanding the age at which patients are diagnosed, and how that varies across demographic groups, can help clinicians and health systems anticipate where care needs will fall.

We studied 224,448 U.S. patients who received a new diagnosis of Parkinson’s disease in a neurology department between January 2017 and November 2025. Patients were included if they had a diagnosis of Parkinson’s disease and at least one outpatient face-to-face visit in the one to three years preceding diagnosis, helping ensure they were established in the health system rather than newly presenting.

Parkinson’s diagnoses were heavily concentrated in older adults. More than 90% of newly diagnosed patients were aged 60 or older, with the largest single group being those aged 70–79 (42.4%), followed by ages 60–69 (24.4%) and 80 and older (23.4%). Younger adults made up a small share of newly diagnosed patients: those under 50 accounted for just 2.6%, and those under 40 for less than 0.9%. This age distribution is consistent with Parkinson’s being a disease primarily of later life.²

Figure 1

Newly Diagnosed Parkinson's Patients by Age Group

Figure 1. The distribution of patients with a new Parkinson’s diagnosis across age groups at the time of diagnosis.

Rather than shifting toward younger ages, as has been observed for several cancers, the age at which patients were diagnosed with Parkinson’s rose slightly over the study period. Median age at diagnosis held steady at 73.0 from 2017 through 2023 and then rose to 74.0 in 2024 and remained there in 2025. Mean age at diagnosis showed a gradual upward drift, increasing from 71.8 in 2017 to 72.8 in 2025, a shift of about one year across nearly a decade.

Figure 2

Median and Mean Age at Parkinson's Diagnosis Over Time

Figure 2. The median age and mean age at first Parkinson’s diagnosis by year, 2017 through 2025.

Age at diagnosis differed modestly across racial and ethnic groups. Hispanic patients had the youngest median age at diagnosis (71), while White patients had the oldest (74); Black patients and patients with another race fell in between at a median of 72. Health care access and patterns in how and when patients present for care might explain some or all of this difference rather than differences in the biology of the disease itself.

Figure 3

Median Age at Parkinson's Diagnosis by Race and Ethnicity

Figure 3. The median age at first Parkinson’s diagnosis within each race and ethnicity group.

These data come from Cosmos, a dataset created in collaboration with a community of Epic health systems representing more than 307 million patient records from 2,000 hospitals and more than 49,000 clinics from all 50 U.S. states, Canada, Lebanon, and Saudi Arabia. This study was completed by two teams that worked independently, each composed of a clinician and research scientist. The two teams came to similar conclusions. Graphics by Brian Olson.

References

Parkinson’s disease. National Institute of Neurological Disorders and Stroke. https://www.ninds.nih.gov/health-information/disorders/parkinsons-disease. Accessed June 29, 2026.
Parkinson’s disease: causes, symptoms, and treatments. National Institute on Aging. https://www.nia.nih.gov/health/parkinsons-disease. Accessed June 29, 2026.
Sung H, Jiang C, Bandi P, et al. Differences in cancer rates among adults born between 1920 and 1990 in the USA: an analysis of population-based cancer registry data. Lancet Public Health. 2024;9(8):e583-e593. doi:10.1016/S2468-2667(24)00156-7
Parkinson disease. World Health Organization. https://www.who.int/news-room/fact-sheets/detail/parkinson-disease. Accessed June 29, 2026.

Data Definitions

Study period: 1/1/2017 to 11/30/2025

Study population: inclusion

Patients:

Newly diagnosed with Parkinson’s disease
- Diagnosis occurred in a department with one of the following specialties: neurology
Another outpatient face-to-face visit in one to three years preceding diagnosis

Study population: exclusion: Patients are only counted in the time period they are first diagnosed
No evidence of the outcome diagnosis before the inclusion diagnosis (including from patient medical history and problem list)

Outcomes: Age at time of new Parkinson’s disease diagnosis

Race and ethnicity: Patient’s self-reported race and ethnicity mapped to standards. Patients were classified as Asian, Black, Hispanic, Multiracial, White, or another race.

Outpatient face-to-face visit: Encounter of type “Office Visit,” “Well Child,” “Follow-up,” or “Telemedicine” with an encounter diagnosis

Parkinson’s disease: A billing or encounter diagnosis with ICD-10-CM code G20* or SNOMED code 49049000