Diagnosing Parkinson’s Disease

Receiving a diagnosis of Parkinson’s disease is difficult. Many questions may arise, including how the diagnosis was made. Unlike a diagnosis of other conditions, there is no one test to diagnose Parkinson's disease. Doctors look at your medical history and perform a full physical and neurological examination. Tests which look for other conditions that could be causing your symptoms, including CT or MRI of the brain and blood work, may also be ordered.

Let’s look at the components of the evaluation:

Medical History

Your doctor will ask you several questions about your symptoms. Some questions might include:

• What symptoms are most concerning to you?
• How do these symptoms impact you each day?
• How have they progressed (if at all)?

You may be asked about many symptoms you haven’t experienced or didn’t think were related, as well as when the symptoms started.

Although you will be asked about your family history of Parkinson's disease, please be aware that the majority of cases of Parkinson’s disease are idiopathic, meaning we don’t know why they occurred. Most patients don’t have an associated family history.

Physical Examination

Your doctor will examine your body for signs of other conditions, which might cause tremor or difficulty walking.

Neurological Examination

Your doctor will perform a neurological examination. This may include many different components to assess your memory, muscle strength, reflexes, and coordination. During this evaluation, your doctor will look for signs of Parkinson’s disease, such as tremor, stiffness, and slowness of movement. In some cases, assessment of your sense of smell may be completed, although this is not typically done.

Tests

Your doctor may order tests to rule out other conditions that could be causing your symptoms. These tests may include blood tests, imaging tests, and sleep studies.

Blood Tests

Blood tests can be used to check for certain conditions that can mimic the symptoms of Parkinson's disease, such as thyroid problems and vitamin B12 deficiency.

Imaging Tests

Imaging tests, such as a CT scan or an MRI scan, can be used to exclude other conditions that could be causing your symptoms, such as a stroke or a tumor. A nuclear medicine study called a DaTscan is sometimes used to help identify if changes consistent with Parkinson’s disease are present.

Sleep Studies

Sleep studies can be used to check for sleep disorders, such as sleep apnea, which can sometimes cause symptoms that mimic Parkinson's disease.

Diagnosis

In summary, Parkinson's is difficult to diagnose because there is no single test for the condition. Evaluations should also be done by a doctor trained in nervous system conditions (neurologist). A neurologist will make a diagnosis based on your medical history, a physical examination, a neurological examination, and any tests that were ordered.

Remember, not every patient will experience all of the common symptoms of Parkinson’s disease, so you don’t want to make assumptions about a diagnosis based on the presence or absence of a single symptom or sign.

We know that there are some conditions that can look like Parkinson’s disease, but over time may change. Your doctor will monitor you closely for signs of those other conditions.

Staging of Parkinson’s Disease

Many patients want to know what “stage” of the disease they are in. There is a staging scale called the Hoehn and Yahr scale, which describes different phases of Parkinson’s disease. This scale is helpful only to give a broad illustration of the symptoms a patient may be experiencing at that specific time but can’t help with prognosis or prediction of the progression of this condition.

Keep in mind that the prognosis for people with Parkinson's disease varies from person to person, and with treatment, most people with Parkinson's disease can live a long and active life.

Approximately 500,000 Americans are diagnosed with Parkinson’s disease but given that many individuals go undiagnosed or are misdiagnosed, the actual number is likely much higher.

If you’re concerned about Parkinson’s disease, talk to your primary care provider about a referral to a neurologist.

Learn more about Trinity Health Michigan Neurosciences and our Movement Disorders programs and clinics, including Parkinson’s diseases.