Similarities and Differences Between Parkinson’s Disease and Essential Tremor
Parkinson’s disease (PD) and essential tremor (ET) fall under the movement disorders category, yet essential tremor is approximately eight times more prevalent than Parkinson’s disease. While these disorders share certain similarities, they also exhibit several notable distinctions. Additionally, they differ in medical coding, where they are assigned different ICD-10-CM codes
Similarities Shared by PD and ET
One of the main symptoms of both PD and ET is tremors, an involuntary and rhythmic shaking. This similarity can cause a healthcare professional to diagnose one of these disorders for the other mistakenly. Therefore, the physician must understand the characteristics of each to identify the correct diagnosis and treatment.
Differences Between PD and ET
According to ParkinsonsDisease.net, the nine fundamental differences between Parkinson’s disease and essential tremor are listed in the table below.
Making a Final Diagnosis Between PD and ET
Once a physician has narrowed the diagnosis down to Parkinson’s and essential tremor, they may perform a nuclear imaging procedure called DaTscan to identify the specific disorder. According to Providence.org, this test offers physicians the ability to observe dopamine levels within the brain and assess the potential degeneration of neurons.
This diagnostic technique involves the fusion of medication with imaging technology known as single photon emission computed tomography (SPECT). In the case of individuals with Parkinson’s, a noticeable depletion of dopamine occurs. Conversely, patients afflicted with essential tremor do not exhibit a decline in dopamine production.
The ICD-10-CM codes for Parkinson’s disease and essential tremor are located in Chapter 6: Diseases of the nervous system, code range G00-G99/Extrapyramidal and movement disorders (G20-G26).
Parkinson’s Disease (PD)
PD currently has one ICD-10-CM code. However, that will change on October 1, 2023, when code G20 becomes category G20 and five new codes are added.
For now, though, coders must still use G20. To find Parkinson’s disease in the Alphabetic Index, go to
Disease, diseased – see also Syndrome; Disease, Parkinson’s G20
In the Tabular, G20 Parkinson’s disease applies to:
- Idiopathic Parkinsonism or Parkinson’s disease
- Paralysis agitans
- Parkinsonism or Parkinson’s disease NOS
- Primary Parkinsonism or Parkinson’s disease
There are notations, inclusions, and exclusions that you need to review before selecting the specific code. These notes are critical to accurate coding.
For example, there is an Excludes1 note at G20 that indicates if the patient has dementia with Parkinsonism, G20 may not be assigned. Instead, G31.83 should be reported.
An Excludes2 note is listed for all codes in the G00-G99 range that indicate if the patient has PD and also has any of the following conditions, both conditions should be reported:
- certain conditions originating in the perinatal period (P04-P96)
- certain infectious and parasitic diseases (A00-B99)
- complications of pregnancy, childbirth, and the puerperium (O00-O9A)
- congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
- endocrine, nutritional, and metabolic diseases (E00-E88)
- injury, poisoning and certain other consequences of external causes (S00-T88)
- neoplasms (C00-D49)
- symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
Essential Tremor (ET)
ET is listed under G25 Other extrapyramidal and movement disorders.
To find essential tremor in the Alphabetic Index, go to:
Tremor(s); essential (benign) G25.0
In the Tabular, G25.0 Essential tremor is applicable to:
- Familial tremor
There is an Excludes1 note that indicates tremor NOS should be reported with R25.1 and not G25.0. Therefore, if the type of tremor is unspecified, R25.1 should be assigned rather than G25.0.
An Excludes2 note is listed to indicate if the patient has a sleep-related movement disorder, G47.6- should be reported in addition to G25.0 for essential tremor.
Also, be sure and look at the additional Excludes2 note at the beginning of the G00-G99 code range (as listed above) in case any additional conditions from that list need to be reported.
Parkinson’s disease and essential tremor are movement disorders that share certain symptoms, mainly tremors. They have many differences, however, and their treatment is completely different. A physician must make an accurate diagnosis to provide the right treatment. A DaTscan imaging test may be performed to assist in this diagnosis. Hopefully, as a medical coder, this post has given you the knowledge you need to accurately locate and verify the correct diagnosis codes for these two disorders.
- Parkinson’s and Deep Brain Neurostimulator Coding in CPT
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- Difference Between Parkinsonism and Parkinson’s Disease (with ICD-10 Coding)
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