Parkinson: early symptoms and early diagnosis
The second neurodegenerative disease after Alzheimer's, Parkinson's begins to signal itself 10-20 years before the first tremors. Recognizing early signs changes the course of the disease.
1. Mechanism: the loss of dopamine
Parkinson's is caused by the progressive degeneration of dopaminergic neurons in the substantia nigra (substantia nigra) in the midbrain. These neurons produce dopamine — a neurotransmitter essential for controlling voluntary movements, motivation, and emotional regulation. When 50 to 60% of these neurons are destroyed, motor symptoms appear. This loss is accompanied by the accumulation of Lewy bodies (aggregates of alpha-synuclein protein) in the surviving neurons.
2. The motor triad
Bradykinesia — slowness of movements
Bradykinesia is the only mandatory cardinal sign for diagnosing Parkinson's. It manifests as a general slowness of movements, a decrease in their amplitude (small steps, small writing — micrographia), and difficulty initiating movement ("feet glued to the ground"). It directly impacts all daily activities: dressing, eating, walking.
The tremor — signature but not mandatory
The typical Parkinsonian tremor is a resting tremor (it disappears during intentional movement), at a frequency of 4 to 6 Hz, often asymmetrical at first (predominates on one side). The so-called "pill-rolling" movement (rolling the thumb on the index finger as if rolling a pill) is characteristic. But 25% of Parkinson's patients do not have a visible tremor.
Rigidity — resistance to mobilization
Parkinsonian rigidity is characterized by resistance to passive movements, present throughout the joint range. Two types are described: cogwheel rigidity (intermittent resistance, characteristic of Parkinson's) and lead-pipe rigidity (uniform and continuous resistance). It is a source of muscle pain and early muscle fatigue.
3. Non-motor symptoms: precursor signs
Non-motor symptoms are now recognized as appearing well before motor signs — sometimes 10 to 20 years before diagnosis. They constitute what is called the "prodromal phase" of Parkinson's. Recognizing these signals can allow for earlier diagnosis and intervention.
| Non-motor symptom | Frequency | Precedes motor signs? |
|---|---|---|
| Anosmia (loss of smell) | 90% | Yes — 5-10 years before |
| RBD (REM sleep behavior disorder) | 50-60% | Yes — may precede by 15-20 years |
| Chronic constipation | 80% | Yes — several years before |
| Depression | 30-40% | Often |
| Cognitive disorders | 30-50% | May precede motor signs |
| Pain | 40-50% | Sometimes |
4. Cognitive disorders in Parkinson's
30 to 50% of patients develop significant cognitive disorders. The most affected areas are executive functions (planning, mental flexibility), processing speed (bradyphrenia), divided attention, and working memory. These disorders, often minimized by the patients themselves, deeply impact autonomy and quality of life. Regular cognitive stimulation is recommended to maintain preserved functions as long as possible.
🧠 DYNSEO support for Parkinson's
• Training "Understanding Parkinson's Disease" — guide for relatives
• Training "Parkinson's in institutions"
• Concentration and Attention Test — assess cognitive functions
• 62 cognitive stimulation tools
FAQ
What is Parkinson's disease?
Neurodegenerative disease caused by the loss of dopaminergic neurons in the substantia nigra. 2nd neurodegenerative disease, affecting 200,000 people in France.
What are the 3 cardinal signs?
Bradykinesia (mandatory), resting tremor, and muscle rigidity. Postural instability is added in advanced stages.
Are tremors mandatory?
No — 25% of patients do not have them. Only bradykinesia is mandatory for diagnosis.
What are the non-motor symptoms?
Anosmia, constipation, REM sleep behavior disorder, depression, cognitive disorders, pain. Many precede motor symptoms by 10-20 years.
Parkinson's and cognitive disorders?
30-50% develop cognitive disorders: executive functions, processing speed, attention. Regular cognitive stimulation is recommended.
Conclusion: Parkinson's beyond tremors
Parkinson's is a complex, multidimensional disease that goes far beyond cinematic tremors. Its non-motor precursor signs, often underestimated cognitive disorders, and variability among patients make it a demanding support. DYNSEO offers specialized training for relatives and professionals, as well as cognitive stimulation tools adapted to the Parkinsonian cognitive profile.
