Assessment of Risk Factors and Early Presentations of Parkinson Disease in Primary Care in a Diverse UK Population

Authors: Cristina Simonet (2022)

Link: https://jamanetwork.com/journals/jamaneurology/fullarticle/2789505

Background Information:

Parkinson’s disease (PD) often begins behind the scenes—individuals might have mood changes, memory issues, constipation, or sleep problems long before classic movement symptoms appear. Much of our understanding comes from research on relatively privileged, white populations, leaving us unsure how early signs show up in more diverse groups.

Purpose of the Study:

This study set out to explore early symptoms and risk markers of Parkinson’s in a large, ethnically and socioeconomically varied UK population—specifically East London. The goal was to see which signs showed up up to 10 years before diagnosis, and whether new early clues—like epilepsy or hearing loss—emerged in these communities.

Methods and Data Analysis:

Researchers examined primary care health records for over a million people (1990–2018), comparing 1,055 people diagnosed with PD to over a million matched controls. They looked for medical codes tied to symptoms and conditions across three time windows: less than 2 years, 2–<5 years, and 5–10 years prior to diagnosis. Associations were tested using logistic regression, and key findings were replicated with data from the UK Biobank.

Key Findings and Conclusions:

Tremor often appeared up to 10 years before diagnosis, while memory complaints often arose 5+ years prior.

Early non-motor signals—like constipation, depression, hypotension—showed up several years in advance.

Surprisingly, epilepsy and hearing loss had new associations with future PD that hadn’t been well reported before.

Midlife risk factors—hypertension and type 2 diabetes—were more common in people later diagnosed with PD (odds ratio ~1.39).

The patterns held even in a high-diversity, lower-income area—suggesting these early signs aren’t limited to affluent or white populations.

In short, the study suggests that a wide range of symptoms—beyond the usual suspects—may surface years before a formal PD diagnosis, particularly in underrepresented groups.

Applications & Limitations:

Clinicians might start connecting dots earlier—for example, seeing hearing loss or new-onset epilepsy in someone who also reports constipation or memory slips may raise a flag for closer follow‑up. Public health and research efforts can now better include diverse populations, widening early detection strategies.

The analyses rely on coded medical records, which may miss subtle or self‑managed symptoms. Association doesn’t prove causation—just because epilepsy showed up more often in people later diagnosed doesn’t mean it contributes to PD onset. Memory complaints, depression, and hearing loss are also common in aging or other conditions, so they’re not specific markers.

Reading this, I was struck by how broad the early sign spectrum seems to be—everything from digestive hiccups to hearing issues to high blood pressure. And yet there’s a caveat: many of these indicators can overlap with normal aging or unrelated health issues. It's tempting to think we could catch PD a decade earlier by tracking these clues—but it’s not that simple. Still, it opens up a more inclusive way of thinking about who might be at risk and how we might spot it sooner in real‑world, diverse populations.