Parkinson's Disease in Black Patients: Diagnosed Late, Treated Less

Parkinson's disease is a progressive brain disorder caused by the loss of neurons that make dopamine, the chemical your brain uses to control smooth movement. It shows up as tremor, slowness, and stiffness, but it can announce itself years earlier through a lost sense of smell, stubborn constipation, or acting out dreams in sleep. In Black patients, the disease is recognized late and treated less aggressively at almost every step: diagnosis, specialist referral, medication, and surgery. The disparities are documented, and they are fixable with earlier referral and a movement-disorder specialist who is actually looking.

Parkinson's disease is a disorder of the nervous system that affects movement and gets worse over time. It develops when neurons in a brain region called the substantia nigra die off. Those neurons make dopamine. As dopamine drops, the brain's movement circuits misfire. By the time the first obvious symptoms appear, most people have already lost 60 to 80 percent or more of their dopamine-producing cells, according to the National Institute of Neurological Disorders and Stroke. That long silent runway is exactly why early non-movement signs matter.

NINDS describes four cardinal motor symptoms. They usually start on one side of the body and stay asymmetric for a long time.

• Resting tremor. A rhythmic shaking, often beginning in one hand or thumb, that is most noticeable when the hand is at rest. It is the first symptom for most people.
• Bradykinesia. Slowness and shrinking of movement: smaller handwriting, less arm swing when walking, a slower shuffle, trouble starting a movement.
• Rigidity. Stiffness and tightness in the limbs or trunk that can be mistaken for arthritis or a bad shoulder.
• Postural instability. Balance and gait problems that raise the risk of falls, usually a later sign.

Parkinson's is not just tremor. A set of non-motor symptoms can precede the movement problems by years, and they are the signs most often dismissed. The Parkinson's Foundation and NINDS describe the most common early ones:

• Loss of smell (hyposmia). Often present years before motor symptoms and frequently unnoticed by the person.
• Constipation. A common and early gut symptom of the disease, not just a diet problem.
• REM sleep behavior disorder. Physically acting out dreams, kicking, punching, or shouting in sleep, is a strong premotor warning sign.
• Depression and anxiety. Mood changes can arrive before any tremor.
• A softer voice or a masked, less expressive face. Family often notices the flattened expression before the patient does.

If you or a parent has several of these together, that is a reason to ask a doctor about Parkinson's specifically, not to wait for shaking.

The disparities are not subtle, and they are documented across large studies. In the largest single-center Black Parkinson's cohort to date, 725 of 2,033 patients, Black patients were diagnosed about four years older than white patients and were less likely to be on medications for both Parkinson's and mood symptoms (Xie and colleagues, Parkinsonism & Related Disorders, 2021). They were also more likely to be cared for through emergency or inpatient services rather than ongoing outpatient care.

Specialist access is a large part of the gap. In a Medicare analysis of more than 138,000 people with Parkinson's, nonwhite patients were significantly less likely to be treated by a neurologist (Willis and colleagues, Neurology, 2011). That matters because the same study found patients who saw a neurologist had a lower risk of nursing-home placement, hip fracture, and death. Seeing a specialist is not a luxury in Parkinson's. It tracks with living longer.

The surgical gap is starker. In a national analysis of inpatient data from 2002 to 2018, white patients with Parkinson's were five times more likely than Black patients to undergo deep brain stimulation, a disparity that persisted even as DBS became more common (Cramer and colleagues, Annals of Neurology, 2022). Follow-up work found the gap was not explained by the surgical workup itself, which points upstream to referral and awareness.

The reasons stack: symptoms blamed on normal aging, arthritis, or the more familiar diabetes and hypertension; fewer referrals to movement-disorder specialists; medical mistrust rooted in real history; and uneven access to specialty care. Dr. Chantale Branson, a neurologist at Morehouse School of Medicine, put the recognition problem plainly to AARP: "We have to reintroduce Parkinson's disease to people. It's not just tremor." Mood symptoms are part of the same picture, which is why our coverage of depression in Black men and anxiety symptoms in Black adults overlaps with the early Parkinson's story.

The research itself is part of the problem. Black Americans make up roughly 8 percent of clinical trial participants while about 75 percent are white, per FDA data cited by AARP. When the people most likely to be undertreated are missing from the studies, the evidence on how the disease presents and responds in Black patients stays thin.

There is no single blood test or scan that confirms Parkinson's. NINDS notes the diagnosis is clinical: a neurologist takes a detailed history, examines you for the cardinal signs, and rules out conditions that mimic Parkinson's. A common mimic is essential tremor, which is a shaking that happens during action rather than at rest. Certain medications, including some used for nausea and psychiatric conditions, can also cause Parkinson-like symptoms. In some cases a specialist orders a DaTscan, an imaging test that looks at dopamine activity in the brain, to help separate Parkinson's from look-alikes. A movement-disorder specialist is the clinician most likely to get this right and to catch it early.

There is no cure, but treatment dramatically improves quality of life, and the gap in who gets it is what makes the disparities so costly. The main options NINDS describes:

• Levodopa (usually combined with carbidopa) is the most effective medication. It replenishes brain dopamine and can sharply reduce tremor, slowness, and stiffness. Other drug classes, including dopamine agonists and MAO-B inhibitors, are used alone or alongside it.
• Exercise and physical, occupational, and speech therapy. Exercise is not just supportive. Regular activity improves balance, flexibility, gait, and strength, and is a genuine part of disease management. Black and Hispanic patients are less likely to report exercise or physical therapy, which is a fixable gap.
• Deep brain stimulation. For selected patients whose symptoms are no longer well controlled by medication, an implanted device sends electrical signals into movement circuits and can restore years of function. This is the treatment with the widest racial gap, so it is worth asking about directly.

The single most useful step is getting in front of the right specialist early, because specialist care in Parkinson's tracks with better outcomes and longer survival. If your symptoms are being brushed off, push for a referral to a neurologist or a movement-disorder specialist, and bring a family member who can describe changes you may not notice, like a flattened expression or restless sleep. You can find a Black neurologist or a Black-serving clinician through our directory. If you want to help close the research gap, ask your specialist about joining a Parkinson's study or registry; the data only improves for Black patients when Black patients are in it.