From the Guidelines
Healthcare providers should be alerted to early Parkinson's disease by key signs and symptoms including resting tremor, bradykinesia, rigidity, postural instability, micrographia, reduced arm swing, stooped posture, masked facial expression, and a soft, monotone voice, as well as non-motor symptoms such as loss of smell, sleep disturbances, constipation, depression, and anxiety. These symptoms are crucial for early diagnosis, as they are associated with the degeneration of dopamine-producing neurons in the substantia nigra of the brain, leading to dopamine deficiency and the characteristic motor symptoms 1.
Key Motor Symptoms
- Resting tremor, typically beginning in one hand, often described as "pill-rolling"
- Bradykinesia, or slowness of movement
- Rigidity, or stiffness in limbs and trunk
- Postural instability, or balance problems
- Micrographia, or small, cramped handwriting
- Reduced arm swing while walking
- Stooped posture
- Masked facial expression, or reduced facial animation
- A soft, monotone voice
Key Non-Motor Symptoms
- Loss of smell, or hyposmia
- Sleep disturbances, particularly REM sleep behavior disorder
- Constipation
- Depression
- Anxiety
- Subtle changes in cognition
- Unexplained fatigue
These symptoms typically develop gradually and asymmetrically, affecting one side of the body more than the other initially 1. Early recognition of these signs is crucial as treatment can help manage symptoms and potentially slow disease progression, though there is currently no cure for Parkinson's disease. The clinical presentation of Parkinson's disease is characterized by progressive degeneration of the dopaminergic neurons in the substantia nigra/striatum, with an estimated interval between initial loss of dopaminergic neurons and the appearance of symptoms of approximately 5 years 1.
From the Research
Key Signs and Symptoms of Early Parkinson's
The key signs and symptoms that may alert a provider to early Parkinson's disease include:
- Prodromal features such as rapid eye movement sleep behavior disorder, hyposmia, and constipation 2
- Characteristic movement difficulties, including tremor, stiffness, and slowness 2
- Psychological or cognitive problems, such as cognitive decline, depression, and anxiety 2
- Bradykinesia with tremor, rigidity, or both, as demonstrated by examination 2
Motor Symptoms
Motor symptoms of Parkinson's disease include:
- Resting tremor, cogwheel rigidity, and bradykinesia 3, 4
- "End-of-dose wearing-off" and "morning akinesia", which describe the transition between a patient's relatively normal motor performance when levodopa is effective and when it has transiently lost its effect on motor responses and parkinsonian symptoms reemerge 4
Non-Motor Symptoms
Non-motor symptoms of Parkinson's disease include:
- Constipation, cognitive impairment, mood changes, and sleep disturbances 2, 3
- Homocysteine synthesis, which has been linked to vascular diseases, cognitive impairment, and dementia 3
Diagnostic Considerations
Diagnosis of Parkinson's disease is based on history and examination, and may be supported by dopamine transporter single-photon emission computed tomography when the presence of parkinsonism is uncertain 2