Since tremor is common in both essential tremor and Parkinson’s disease, people often misunderstand and consider them the same. However, both are quite different conditions and there are many ways to differentiate between the two.
Here are 10 differences that help to distinguish between essential tremor and Parkinson’s disease.
1. The Difference in the Specificity of Tremor
Tremor is the key symptom in essential tremor. The diagnosis of essential tremor is based on the presence of tremor.
In the case of Parkinson’s disease, tremor is not the only symptom. There are other motor symptoms that are specific to Parkinson’s disease. These include slowness of movement, rigidity, and balance problems. The disease is said to be Parkinson’s when besides tremor these symptoms are also present in a patient.
2. The Difference in Non-motor Features
In Parkinson’s disease, the non-motor symptoms are more common and sometimes they can overshadow other signs of the disease. In fact, researchers started to believe that the non-motor symptoms of Parkinson’s appear many years before the onset of its typical motor symptoms. These include constipation, loss of smell, and abnormal sleep behavior.
Essential tremor can also be characterized by its non-motor features. However, they are less intensive and rarely reported in a patient. Some of the non-motor signs that may develop during the course of the disease include sleep disturbances, loss of smell, and personality changes.
3. The Difference in the Appearance of Tremor
Essential tremor is usually an action tremor. It means that it appears when the hands are performing activities like drinking, eating, and writing.
On the other hand, tremor in Parkinson’s disease appears when the hands are at rest. This is why it’s also known as resting tremor.
This is an easy way to differentiate between the two tremors and often used as a useful diagnostic criterion at the clinic.
4. The Difference in the Location of Tremor
In both cases, tremor appears primarily in the hands. However, other parts may also be affected.
In the case of essential tremor, the head and voice are mostly affected after the hands. While in Parkinson’s tremor, legs are more affected than head and voice.
In essential tremor, the tremor starts on both sides of the body. Whereas, Parkinson’s tremor first appears on one side and gradually spreads to the other side.
5. The Difference in the Genetics
Genetics plays a big role in the development of essential tremor. Around 50-70% of people with essential tremor have a family history of the condition. There are more than 11 defective genes that are linked to essential tremor. However, no specific mutations have been identified in them.
The contribution of genetics in Parkinson’s disease is small. It accounts for 10% of Parkinson’s cases. To date, more than 15 genes have been identified that are linked to Parkinson’s disease.
6. The Difference in the Age of Onset
Essential tremor can appear at any age. It usually affects people in their 40s or above. Childhood cases are also reported.
Parkinson’s tremor affects older people. It’s most common in people who are above the age of 60. That’s why Parkinson’s is often called the disease of old people.
7. The Difference in Handwriting Style
People with essential tremor are generally writing in a large and jerky way. While the handwriting of Parkinson’s tremor patients tends to be small. They usually write in a slow and steady manner.
8. The Difference in the Prevalence
Essential tremor is more common than Parkinson’s tremor. There are approx 41 million people worldwide are living with this condition. The current estimate shows that 4 out of 100 individuals over the age of 40 are affected by essential tremor.
The number of people suffering from Parkinson’s disease is estimated to be 10 million. The statistic shows that around 4 percent of people with Parkinson’s are diagnosed before the age of 50.
9. The Difference in Gender
Essential tremor tends to affect both men and women equally. Parkinson’s tremor on the other hand is more common in men than in women. Scientists are still trying to understand why sex and gender differences exist between the two conditions.
10. The Difference in Medication
Medications used to treat tremors in both cases are different. The most common drugs used to treat essential tremor include primidone and propranolol. Primidone is a beta-blocker that is used as first-line therapy. Propranolol is an anti-epileptic drug and is prescribed when a patient is not responding to primidone. When both drugs failed to improve the tremor, a drug called botox is used in the form of injection.
Parkinson’s tremor is often treated with anticholinergic drugs like benztropine and trihexyphenidyl. The other commonly used drug is levodopa, which is prescribed when symptoms like the slowness of movement and rigidity are also present.