Understand & act

Parkinson's disease is a chronic condition that progressively affects the ability to produce movement. Gradually, the symptoms of the disease appear and worsen over time. However, you have the power to act to maintain a good quality of life and your daily activities.

What is Parkinson's disease ?

Parkinson’s disease is a neurodegenerative disease that is mainly manifested by movement disorders. Unlike many other cases of neurological damage, the anomaly at the base of Parkinson’s disease is known and is explained by the loss of neurons from a part of the brain called the substantia nigra.

These neurons, which control movement, communicate with each other through a chemical element, dopamine. The decrease in the number of these neurons leads to a drop in the level of dopamine and therefore, less good management of movements and the appearance of motor symptoms. Other parts of the brain are also affected by the disease, which explains the appearance of non-motor symptoms.

The loss of neurons is a slow process. Motor symptoms begin to appear when nearly 80% of dopaminergic neurons have disappeared. The death of neurons is caused by a combination of environmental and genetic factors. Although there is no cure for Parkinson’s disease yet, there are several treatments to alleviate its symptoms and therefore improve the quality of life of people who suffer from it.

At the time the diagnosis is made, it is estimated that 80% dopamine-producing cells have already stopped working.

Évolution de la maladie

Each person with Parkinson’s disease is unique and, as such, prone to developing different symptoms. However, since Parkinson’s is a progressive disease, existing symptoms tend to worsen, and new symptoms may appear. It is difficult to assess how quickly Parkinson’s will progress for each person affected. In general, the first stage of the disease is a honeymoon period which can last from 3 to 8 years and which is defined by a practically normal life. During this period the treatments generally work best. It is possible that degeneration occurs more quickly in people who are older when the first symptoms appear. It is also possible that Parkinson’s progresses more slowly when the main symptom is tremor, especially if tremor starts on one side.

You can live an active life while having Parkinson’s, depending on your age when symptoms first appear, how you manage your symptoms, and your overall health. In most cases, Parkinson’s disease does not shorten life expectancy. However, as one ages and the disease progresses, the risks increase. Thus, poor balance can lead to falls, and swallowing problems, if neglected, can lead to pneumonia. Parkinson’s is a chronic (long-term) condition that requires ongoing vigilance and management to maintain a good quality of life.



Four motor symptoms are the main clinical manifestations on which the diagnosis of the disease is based. The main sign making the diagnosis possible is the presence of two of the first three symptoms.

Tremor is an uncontrollable, rhythmic, back-and-forth repetitive movements that affects one or more parts of the body. It is the symptom of Parkinson’s disease best known to the general public. The characteristics of the tremor is an important part of the diagnosis.

The characteristic tremor of Parkinson’s disease is a resting tremor.

  • It occurs when the limb is inactive, for example, when the person is seated and their hand is resting on their thigh.
  • It decreases during sleep and when the limb is actively used.
  • It tends to subside when a movement is made voluntarily.

Tremor remains one of the most troublesome symptoms of the disease. It is also the most visible and well-known symptom of Parkinson’s disease among the general public. Tremor usually affects only one side of the body, especially in the early stages of Parkinson’s disease. But as the disease progresses, both sides can be affected. In general, the intensity of tremor stabilizes at some point and it stops getting worse.


Stiffness associated with Parkinson’s disease refers to stiffness in the limbs or torso. It is an excessive tension in the muscles that prevents them from stretching and relaxing. It is the most common symptom of the disease. It can affect one side of the body or both.
Stiffness is one of the motor symptoms of Parkinson’s disease, along with slowness of movement and tremors. It does not affect everyone living with the disease.

Some people feel it on one side of the body while others feel it on both sides. It usually appears in the muscles of the shoulders, arms and legs. But it can also be felt in the neck, trunk, hips and ankles.

Stiffness can cause :

  • Pain
  • Cramps
  • Loss of facial expression
  • Communication difficulties
  • Inability to properly hold utensils
  • Difficulty dressing and buttoning clothes
  • A stooped posture
  • A reduction in range of motion
  • Difficulty in getting out of bed or a chair

Stiffness is often confused with other diseases or symptoms associated with aging, such as arthritis, especially in the early stages of the disease.

Slowness of movement, also called bradykinesia, is one of the most common symptoms of Parkinson’s disease. It affects dexterity and coordination of all movements.

Bradykinesia involves a slowness in performing (rather than initiating) movement as well as a reduced range of motion.

Bradykinesia, along with tremors and stiffness, are the main motor symptoms of Parkinson’s disease. It can affect only one side of the body or both.

In everyday life, bradykinesia manifests itself, among others, by :

  • a reduction in fine dexterity which will cause difficulty in buttoning one’s clothes, tying one’s shoes
  • grooming slowness in walking, speaking and affecting the style of writing
  • reduction in the size of steps, the frequency of blinking of the eyes and facial expression

Daily tasks and activities therefore take longer to complete.

Bradykinesia can be particularly frustrating because it is often unpredictable. One moment you can get around easily, and the next you need help. As Parkinson’s disease progresses, certain tasks may become impossible to perform.


Losing your balance and preventing falls is part of daily life for those with Parkinson’s disease. With time, almost every person suffers from postural instability, but you have some control over the severity of balance issues and the frequency of falls.

Parkinson’s disease significantly affects gait. The motor symptoms of the disease, such asrigidity,freezingand changes in posture disrupt the sense of balance and can lead to falls.

Nearly two-thirds of people living with the disease have fallen in the past year, and half of these cases resulted in injuries. Fortunately, there are many resources that can help you improve your balance and prevent these falls.


Freezing is a leg locking that prevents you from taking steps while walking. People usually describe it as a feeling of having their feet glued to the ground.

Freezing can occur when you want to start walking, while walking or when you turn around. You may also be affected during repetitive movements, such as talking, writing or brushing your teeth or hair.

Freezing episodes last a few seconds to a few minutes, though not everyone with Parkinson’s disease is affected by them.


Dysphagia is a feeling of discomfort or obstruction when saliva or food passes from the mouth to the stomach. Although it is more common in the advanced stages of Parkinson’s, it can occur at any stage of the disease.

Close to 90% of people living with Parkinson’s disease have difficulty swallowing.

Signs of a swallowing disorder can sometimes be subtle and go unnoticed, which is why you need to carefully note any changes in your ability to swallow.

Dysphagia is usually accompanied by :

  • Excess saliva
  • Difficulty or inability to eliminate food from the mouth
  • Feeling that food sticks or gets caught in the throat
  • Rough voice
  • Pain when swallowing food
  • Throat discomfort

Difficulty swallowing during meals and excess saliva on the corner of the lips can also cause embarrassment that can increase social isolation.

Given the risks associated with swallowing disorders (dehydration, undernutrition, choking, pneumonia), it is important to discuss it as soon as possible with your neurologist. Early treatment will help preserve your health and quality of life.

Muscle contractions and pain are common in people living with Parkinson’s disease. This can be caused by dystonia or muscle cramps, which need to be differentiated to be treated effectively.

Dystonia is a movement disorder caused by abnormal
signals to the brain. These signals lead the muscles to contract and twist involuntarily. These muscle spasms or twisting movements cause parts of the body to flex in an unusual and painful way.

Muscle cramps are mainly caused by a lack of oxygen, water, or waste elimination directly in the muscles. The cause is therefore local. The muscles flex and contract, causing sudden and sharp pain. Muscle cramps are painful but most often are not visible.


non motors

Many patients do not realize that these other symptoms are related to Parkinson's disease. Therefore, they are not processed. These changes, known as non-motor symptoms, can also impact quality of life.

Fatigue is one of the most common and least recognized symptoms of Parkinson’s disease. Yet, it significantly affects the quality of one’s life. A consultation with a neurologist as well as the adoption of a better lifestyle can restore a good quality of life.
About 50% of people living with Parkinson’s disease are affected.

It is difficult to describe or even measure fatigue. People living with Parkinson’s disease can experience moments of intense fatigue. This fatigue occurs even if the person has not made any physical effort or done any type of activity; it also does not improve with rest. Its severity is not related to the motor symptoms.

The impact and severity of fatigue on one’s daily life varies from individual to individual and its intensity can also change throughout the day. 

You may feel energetic and able to complete daily tasks at certain times of the day, and lack the energy to do small, everyday things at other times.

Implementing actions to better manage fatigue is essential to maintain a good quality of life. Talk with your neurologist about it.


Communication difficulties, especially speech impairments, contribute to the isolation of people living with Parkinson’s disease. Appropriate treatment by speech therapists can help you maintain productive interactions with your spouse, family, friends, and colleagues.

Up to 90% of people with Parkinson’s disease experience changes in voice, speech and language. Micrography, i.e. increasingly small writing, can also negatively affect communication.

Some changes in speech are:

  • Bradykinesia: articulatory movements of the mouth, tongue and lips are slower and weaker.
  • Tremors and small repetitive movements of the lips and tongue
  • Frozen and rigid face that gives the impression that the person speaking has no emotions
  • Decreased saliva control
  • Speech acceleration: the person speaks very fast and it may seem as if he or she is stuttering and parts of words are missing.
  • Palilalia: resembles stuttering because of frequent syllable repetition of a word (e.g., pa-pa-pa-parachute)


 Anxiety is normal when anticipating a difficult or threatening situation and it allows us to take the necessary precautions to avoid risks. Most of the time, anxiety is useful and disappears once the anticipated situation is over. Some anxiety episodes are associated with a decreased effectiveness of Parkinson’s medications.

Anxiety is very common in the general population, and three times as common in people with Parkinson’s disease. Episodes can also be 10 times more intense.

Mild anxiety can be characterized by a feeling of nervousness and premonition disproportionate to the circumstances. In more severe cases, anxiety can induce panic attacks without direct cause.

In most cases, anxiety episodes are justified, but chronic anxiety and a lack of direct triggers can be an impediment to accomplishing daily tasks and activities.

Anxiety is expressed through psychological symptoms (constant worry, excessive nervousness, feelings of fear, avoidance of social situations, difficulty concentrating) and physical symptoms (pounding heartbeat, sweating, increased shaking, dizziness, difficulty breathing).


Mild cognitive impairment, such as memory loss, can be part of the normal aging process. However, some symptoms can also be caused by Parkinson’s disease.
Mild cognitive impairment affects around 1/3 of people with Parkinson’s disease.

Parkinson’s disease slows down all movement of the body. This general slowdown also affects cognitive abilities. Memory, orientation, attention, concentration, the ability to learn, abstract thinking, judgment and language can be affected. 

Mild cognitive impairment is characterized by difficulty:

  • Paying attention
  • Following a complicated conversation
  • Concentrating to read
  • Planning complex activities
  • Finding solutions to problems
  • Taking decisions
  • Formulating your thoughts
  • Finding the right words
  • Keeping information in memory
  • Learning new things
  • Imagining things
  • Orienting yourself
  • Doing several things at the same time

These mild cognitive impairments, although disturbing, do not compromise the performance of daily activities. Their appearance doesn’t mean that you have dementia or that it will develop later on. Occasionally forgetting phone numbers or names when you’re over 70 is perfectly normal.

Dementia is diagnosed when problems with memory and thinking take up more space in your life and prevent you from performing everyday tasks.


It’s common to feel depressed from time to time. Depression is more than a temporary feeling of sadness or unease. It is a symptom associated with Parkinson’s disease. With outside help and appropriate treatments, it is possible to overcome it and enjoy a good quality of life.

Almost 1 in 5 people living with Parkinson’s disease have depressive episodes.

Depression affects people in very different ways and can cause a diverse set of emotional, cognitive, and also physical symptoms.
  • Loss of interest in usual hobbies or daily activities
  • Feeling helpless or hopeless almost every day
  • Feelings of worthlessness, anguish, worry or fear
  • Inability to feel joy
  • Difficulty or inability to carry out one’s daily routine
  • Difficulty concentrating
  • Loss of self-confidence
  • Persistent sadness
  • Low energy or feeling very tired
  • Changes in appetite, usually in conjunction with a change in weight
  • Sleep disturbances (insomnia or excessive sleep)
  • Dark or suicidal thoughts (in extreme cases)

Not all people with depression present with the totality of these symptoms.



People who live with Parkinson’s disease feel pain more acutely than others. Muscle stiffness, immobility, poor postures and fluctuations in the effectiveness of treatment are among the most common causes of pain. 

50% of people with Parkinson’s disease suffer from pain.  The pain suffered affects a wide variety of areas, has very different causes and requires different treatments.



Drops in blood pressure occur during sudden changes in position. These pressure drops can cause dizziness or falls. They can be treated with simple everyday measures or medication.

One in three people with Parkinson’s disease experience drops in blood pressure


Blood pressure is ameasure of the pressureyour heart uses topump bloodthrough your body. It fluctuates naturally throughout the day. It is balanced throughout the body, from the feet to the brain.

These pressure drops, caused by the transition from lying or sitting to standing, are actually drops in pressure in the brain.

They can cause several symptoms including:

  • Feeling dizzy or light-headed
  • Blurred vision
  • Weakness
  • Confusion
  • Fainting


Hallucinations are the perception of objects or sounds that do not exist. These perceptions are rare and can occur in the later stages of Parkinson’s disease. They do not mean that you have dementia and they can be treated.

Nearly 1/3 of people with Parkinson’s disease experience hallucinations

Hallucinations can take different forms:

  • Visual: People, especially loved ones, or absent pets.
  • Auditory: Sounds, music or voices that others cannot hear.
  • Tactile: Feeling that something or someone is touching you or is near you when this is not the case.
  • Taste: Tasting food that has not been eaten.
  • Smell: An odour that others do not smell.

Visual hallucinations are the most common in people living with Parkinson’s disease. Auditory, taste, smell and touch hallucinations are quite rare.

Hallucinations are different from delusions, which are thoughts, beliefs or worries that have no basis in reality.

Hallucinations often occur in low light conditions or when the person is in an altered state of consciousness, such as when the person is just waking up.


The slow and decreased muscle coordination typical in Parkinson’s disease also affects the gastrointestinal tract. Stool becomes more difficult to pass and the frequency of bowel movements is reduced to less than three per week. Lifestyle changes and treatments exist to address constipation.

Constipation affects more than 60% of people with Parkinson’s disease.

Constipation is common in the general population. But in people living with Parkinson’s disease, the symptoms of the disease can increase constipation problems.

You can relieve constipation with changes in your lifestyle and eating habits.


Dementia is a set of cognitive impairments that progressively develop to the point of interfering with daily activities. It can affect people living with or without Parkinson’s disease. Not everyone with mild cognitive impairment will develop dementia.

Nearly one-third of people with Parkinson’s disease will eventually develop dementia.

The risk of developing dementia increases significantly after the age of 75, with or without Parkinson’s disease. However, people living with the disease are at greater risk.

The onset of dementia is subtle and its progression is usually slow. During the first few years, people maintain their independence. Their memory is compromised, but less so than in Alzheimer’s disease. Later on, their judgment may be affected, making it difficult to manage daily activities. Managing complex concepts or several tasks at once becomes impossible. The ability to visualize objects in time and space gradually decreases, which explains why people affected get lost easily. Finally, their general mood and personality may change.

Dementia takes different forms in different people, on different days, and even within the same day.


People living with Parkinson’s disease sometimes notice changes in the condition of their skin. These problems may be minor, but for some, they can affect quality of life.

It’s common for people living with Parkinson’s disease to have skin that is oily, red, irritated and/or flaky. The amount of sweat produced may also change. Although these problems are rarely dangerous, they can cause embarrassment and discomfort.

The most common problems include:

  • Seborrhea
  • Seborrheic dermatitis
  • Excessive sweating
  • Inadequate sweating


  • Melanoma

Weight loss is common in people living with Parkinson’s disease. It is usually mild to moderate, and occurs mostly in the later stages of the illness. 

Weight loss should be addressed as quickly as possible, because it can exacerbate both motor and non-motor symptoms of Parkinson’s disease. If not treated properly, it can lead to significant problems, such as osteoporosis (bone deterioration) and increased risk of infection.


People living with Parkinson’s disease often experience vision problems. However, these problems are not always related to Parkinson’s disease.

2/3 of Parkinson’s patients have eyelid movement abnormalities.


Dental health can affect well-being and quality of life. Certain symptoms of Parkinson’s disease can cause dental and oral problems. 

Having a healthy mouth enables you to chew, taste, swallow and speak properly. Strong, healthy teeth help you enjoy your food.


Nightmares and vivid dreams are common and harmless.
In contrast, REM sleep behaviour disorders are a feature of neurodegenerative diseases such as Parkinson’s disease. People then physically externalize their dreams. These individuals and their spouses may become at risk of injury.

General population, 40 years and older: < 3%.
People with Parkinson’s disease: 50%.

REM sleep behaviour disorders can appear several years before Parkinson’s disease. In these often unpleasant dreams, people can become physically or verbally violent, involuntarily and unconsciously.

The most common symptoms of REM sleep behaviour disorders are:

  • Sounds (screaming, swearing, laughing)
  • Physical (kicking, punching, flapping arms or jumping out of bed in response to action-packed or violent dreams)

When they wake up, people with these disorders can remember their dreams, but not what they did during those dreams. These disorders are a risk for both the person with the disorder and the partner who shares the bed. In addition, they can be very frightening for the partner. It is important to talk about this disorder and make the sleeping environment safe to reduce risks.


Gastrointestinal issues are some of the most common and distressing problems reported by people living with Parkinson’s disease.

Parkinson’s disease slows down both the upper and lower gastrointestinal tracts. In the lower tract, this results in constipation. In the upper tract (your stomach), it can lead to nausea, vomiting and bloating. This phenomenon can cause discomfort and affect your nutrition.



Interest in sexuality and the sexual functions of both men and women start to decline from the age of 50. Parkinson’s disease can cause certain psychological and physical disorders, resulting in sexual dysfunction that contributes to a decline in sexual activity.

Half of people with Parkinson’s disease have sexual dysfunctions.

Sexual dysfunctions reported by men and women differ. They can be embarrassing or frustrating and can affect marital relationships.

Sexual dysfunctions include:

  • Erectile dysfunction (in men)
  • Pain during intercourse (in women)
  • Decrease in sexual interest or desire
  • Difficulty reaching orgasm


Age is the main cause of many bladder problems. Parkinson’s disease can make some of these conditions worse. There are many options for treating overactive bladder.

One third of people with Parkinson’s disease have bladder problems.

The bladder stores the urine produced by the kidneys. Urinating involves two simultaneous processes: 1) the contraction of the bladder muscles and 2) the opening of a valve so that the urine can be drained.

When the bladder contains a certain volume of fluid, a reflex signal is sent to the brain to warn it that it is time to go to the bathroom. The brain then sends a signal to release the pressure on the bladder muscles and strengthen the valve tone. Once on the toilet, the brain commands the bladder muscles to contract and open the valve.

The most common problems are usually related to:
Overactive bladder
Feeling that the bladder is full
Frequent and/or urgent need to urinate, including at night
Difficulty holding it in
Involuntary urine leakage (incontinence)

Hypoactive bladder
Difficulty starting to urinate
Feeling that the bladder is not completely empty
Urinary leakage

People living with Parkinson’s disease can be affected by both types of problems.


Some people living with Parkinson’s disease experience partial or complete loss of smell (hyposmia and anosmia, respectively). It becomes more difficult for them to detect, identify and differentiate between smells. Since smell and taste are closely intertwined, the latter can also be affected.

Hyposmia in the general population: 15%
Hyposmia in those with Parkinson’s: 70-90%
Anosmia in those with Parkinson’s: ⅓

Loss of smell can occur several years before the onset of the motor symptoms of Parkinson’s disease. Of course, not everyone who experiences loss of smell will develop Parkinson’s disease.

Loss of smell often goes unnoticed. When people do notice it, they tend not to realize that it can be associated with Parkinson’s disease. When the motor symptoms appear and they discuss the disease with their doctor, many patients remember having lost their sense of smell years earlier.

 Here are a few of the ways in which hyposmia and anosmia can affect daily life:

  • Difficulty choosing food
  • Loss of interest in eating, followed by weight loss
  • Difficulty identifying potential danger (fire, spoiled food, etc.)
  • Sadness, depression
  • Difficulty adhering to social standards of hygiene (difficulty detecting body odour)

Loss of smell is an important lead for researchers that could contribute to earlier Parkinson’s diagnoses.


While fatigue and falling asleep during the day are normal for seniors, people living with Parkinson’s disease often experience excessive sleepiness caused by disrupted nighttime sleep.

Daytime hypersomnolence is a condition that involves feeling very sleepy or napping too much during the day.

You may have hypersomnolence if:

  • You fall asleep right after breakfast
  • You need naps that last over 2 hours
  • You fall asleep while reading or watching TV
  • You nod off during conversations or meals
  • You have the sudden urge to sleep when eating, working, walking or reading (sleep attacks)

Short naps after meals or physical activity are not symptoms of excessive sleepiness.

Hypersomnolence reduces quality of life by decreasing the time available for meaningful activities and contributing to mental confusion.


Related diseases

People commonly associate tremor with Parkinson’s disease. However, other neurological conditions share many symptoms with Parkinson’s and can be confused with it. It is important to be able to distinguish between these different diseases.

Tremor is the only symptom of essential tremor. People with this condition do not experience slow movementsrigidity or walking difficulties typical of Parkinson’s disease.  The tremor in essential tremor mainly affects the hands, but the head and voice can also be involved.

Unlike Parkinson’s disease, tremor affects both hands and does not decrease with movement, such as when holding a cup or writing.

Essential tremor, which is 5 times more frequent than Parkinson’s disease, has a strong hereditary component.

Parkinsonian syndromes are a group of rare diseases that have symptoms like Parkinson’s disease, such as slow movements, tremors, muscle stiffness and balance disorders, but in these syndromes, other severe symptoms are added to the typical symptoms of Parkinson’s disease.

  • Progressive supranuclear palsy: Frequent falls, difficulty moving the eyes, and emotional and personality changes
  • Multiple system atrophy: Dizziness, difficulty keeping balance, fainting, constipation, erectile dysfunction and urinary retention
  • Corticobasal degeneration:Severe incoordination of movements, accentuated stiffness, jerks or spasms, usually of the hands
  • Lewy body disease:Cognitive decline, hallucinations and loss of alertness and attention.


In the early stages of these diseases, diagnosis is difficult. The presence of non-typical symptoms of Parkinson’s disease such as impaired vision, early falls or significant cognitive impairment will lead to a diagnosis of a Parkinsonian syndrome.

Parkinsonian syndromes often progress more quickly than Parkinson’s disease and, unfortunately, few therapeutic interventions are effective in alleviating these conditions. Beyond the neurologist’s support, the affected person can greatly benefit from the help of other health professionals such as physiotherapists, occupational therapists, neuropsychologists and speech therapists.

Normal pressure hydrocephalus is caused by an accumulation of fluid in the brain. A brain imaging test can differentiate it from Parkinson’s disease. 

This neurological condition usually has symptoms similar to Parkinson’s disease, such as difficulty walking, cognitive problems, dementia and urinary problems.

Some medications can cause reversible Parkinson’s syndrome. These drugs block the activity of dopaminergic neurons, artificially causing motor symptoms similar to those of Parkinson’s disease. 

Medications that can cause this syndrome are usually prescribed to treat:

  • Severe psychiatric disorders
  • Nausea and intestinal mobility problems
  • Migraines
  • Tourette’s syndrome

Stopping these medications makes the Parkinsonian symptoms disappear.

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