Personality changes in Parkinson’s disease: symptoms, causes, treatment, tips

Personality changes, which can manifest themselves in increased irritability, depressive moods, dementia or delusional thinking, for example, are a common side effect of Parkinson’s disease. Such personality changes often not only reduce the quality of life of those affected, but can also be experienced as stressful by relatives. It is therefore important to treat not only the motor symptoms of Parkinson’s, such as tremors or muscle stiffness, but also the mental impairments of those affected.

We would like to take this opportunity to inform you about the symptoms of personality changes in Parkinson’s, their causes and how they can be treated medically. We have also compiled tips for relatives that can make life with a person with the disease easier.

What is a personality change?

“I didn’t marry this person” is how relatives often describe the changes in a person’s character that are caused by a neurodegenerative disease such as Parkinson’s, for example. The affected person shows psychological changes, certain behavioral abnormalities that were not previously characteristic of them. Their behavior can be unpredictable for relatives and present them with great challenges in dealing with their loved one. As a rule, the person with the illness does not notice any changes in themselves and therefore shows a corresponding lack of understanding.

Personality changes in Parkinson’s disease: symptoms

The changes in personality that are triggered by Parkinson’s disease or occur as a side effect during the course of drug treatment can manifest themselves in very different ways. The changes often relate to emotional experience, but are frequently also cognitive in nature. The following personality changes are frequently observed by doctors in Parkinson’s patients:

• Depressive mood or depression
• Lack of drive and lack of motivation
• Fear
• Psychosis (hallucinations, delusions)
• Cognitive problems (e.g. concentration and memory disorders, confusion, disorientation and even Parkinson’s dementia)
• Irritability and aggressiveness
• Mood swings
• Emotional instability
• Stubbornness
• Compulsive behavior, e.g. sex addiction, shopping addiction, gambling addiction, eating addiction

Depression and anxiety in Parkinson’s disease

Depression and anxiety often appear at an advanced stage, with around 40 percent of Parkinson’s patients said to be affected. However, these symptoms can also become noticeable at the beginning, as the first signs. Either only one of the mental disorders is evident or both together.

Cause of depression and anxiety in Parkinson’s disease

Anxiety and depression arise because the finely tuned composition of neurotransmitters in the brain is out of balance in Parkinson’s patients. For example, the lack of dopamine in the brain caused by the disease promotes feelings or states such as anxiety, dejection, hopelessness, apathy (numbness and loss of interest), increased brooding, lack of drive or social withdrawal. These are all typical symptoms of clinical depression.

However, the motor symptoms of Parkinson’s, such as slowed movements (bradykinesia) and postural instability, also play a role in the development of anxiety. This is because Parkinson’s sufferers tend to fall more often, which brings with it the risk of injury. As a result, many sufferers become anxious and try to avoid movement wherever possible. The motor impairments also lead to many patients feeling uncomfortable around other people and increasingly withdrawing from social life. This isolation in turn often leads to sadness, hopelessness and loneliness – and to depression.

Treatment of depression and anxiety in Parkinson’s disease

The treatment of depression or anxiety in connection with Parkinson’s is often carried out with the help of cognitive behavioral therapy. Doctors can also initiate drug treatment, for example with antidepressants, to improve the balance of neurotransmitters in the brain and alleviate symptoms such as numbness or panic attacks.

Hallucinations and delusions in Parkinson’s disease

In the advanced stages of the disease, many patients develop psychosis, which can manifest itself in the form of hallucinations or delusions. According to one study, almost 75 percent of people who have been living with Parkinson’s disease for at least 20 years are affected. Hallucinations are also known as “delusions”, as in this case people see something that does not exist in reality. Those affected often think they see people or animals that are not actually there. This happens, for example, when they see a shadow and interpret something into it. However, they may also smell, hear or touch things that healthy people do not perceive.

In addition, delusions often play a role in advanced Parkinson’s disease. People are then firmly convinced that someone is trying to harm them, for example. One example of this is that they believe that someone is trying to poison them with food, for example. Those affected may also feel persecuted by someone or accuse their partner of being unfaithful. These psychoses pose a major challenge in the care of an affected relative and are often the reason for an inpatient stay in hospital or placement in a care home.

Cause of psychosis in Parkinson’s disease

One cause of psychosis is the use of medication for Parkinson’s disease, such as levodopa (L-dopa), which is intended to compensate for the lack of dopamine in the brain caused by the disease. This is because the dopamine level in the brain needs to be increased in order to alleviate motor symptoms such as tremors or slowness of movement in Parkinson’s disease. However, too high a dosage can lead to an excess of the neurotransmitter dopamine in the brain, which can trigger psychotic states.

Treatment of psychosis in Parkinson’s disease

It is important that you inform your neurologist about hallucinations or delusional thinking, as a change in medication can bring about positive changes. The use of antipsychotics can also be considered as a therapy. However, treatment with these drugs should be viewed critically, as common drugs can inhibit the absorption of dopamine, which is produced in the brain with the help of levodopa, and therefore worsen the motor symptoms.

Parkinson’s dementia

Cognitive disorders, including diagnosed Parkinson’s dementia, also pose an increasing problem for relatives and sufferers as Parkinson’s disease progresses. Between 30 and 40 percent of all Parkinson’s patients are diagnosed with Parkinson’s dementia as their disease progresses. Parkinson’s dementia manifests itself, for example, in problems with attention span. Patients can no longer concentrate on one thing, and thinking also slows down. In particular, tasks that require a high level of concentration can no longer be completed as well.

The memory disorders typical of Alzheimer’s are less prominent in Parkinson’s when it comes to cognitive symptoms, although they do occur. Instead, those affected often appear mentally confused and have difficulty finding their way around reliably. Their ability to solve problems, plan everyday life sensibly or make decisions decreases significantly. Parkinson’s patients also have noticeable language problems such as difficulty finding words. If Parkinson’s dementia is more advanced, those affected can only cope with everyday life with nursing support.

Cause of Parkinson’s dementia

One cause of Parkinson’s dementia is the lack of dopamine as a result of the accelerated death of the dopamine-producing nerve cells (neurons) in the black substance (substantia nigra). Dopamine is not only involved in controlling our movements, but also plays an important role in our perception, information processing, memory and emotional experience. As a result of a dopamine deficiency, another neurotransmitter that also controls our mental functions decreases: acetylcholine. We also notice a lack of acetylcholine through poorer mental performance.

Doctors see another cause of Parkinson’s dementia in the protein deposits, the so-called Lewy bodies, which are deposited in the nerve cells of the substantia nigra in the midbrain in affected patients, causing the death of the nerve cells and having a negative impact on thought processes. Nevertheless, not all Parkinson’s patients, who also have these protein deposits in the nerve cells of the substantia nigra, develop dementia. In the late stages, however, many patients develop Parkinson’s dementia, probably because the deposits also spread to other areas of the brain.

Parkinson’s dementia versus Lewy body dementia

This is because these protein deposits also occur in so-called Lewy body dementia. Here, however, these protein clumps are found more in the nerve cells of the cerebral cortex (gray matter) and less in the substantia nigra. If the cognitive disorders occur within a year of the motor symptoms of Parkinson’s, doctors speak of Lewy body dementia. If the signs of dementia only appear around 15 years after the motor symptoms, this is referred to as Parkinson’s dementia.

Despite the parallels to Parkinson’s dementia, Lewy body dementia is seen as a separate form of dementia. In this understanding, it is counted among the atypical Parkinson’s syndromes. This includes various other diseases with similar or partly identical symptoms to Parkinson’s disease, but with different causes.

Treatment of Parkinson’s dementia

Parkinson’s dementia is often treated with the active ingredient rivastigmine. This ensures that a larger amount of the missing neurotransmitter acetylcholine is available in the body, so that cognitive performance may increase again. Another option is therapy with the active ingredient donepezil.

Irritability and mood swings in Parkinson’s disease

In addition to motor and cognitive symptoms, many people with Parkinson’s syndrome also experience turbulence in their emotional experience. Those affected can become overly emotional, for example by starting to cry at trivial things or exploding in a sudden outburst of anger. Many are prone to increased irritability or even aggressive reactions when they are asked to do something against their will. This is because advanced Parkinson’s patients are often stubborn and intransigent.

Furthermore, it is not unusual for their mood to change quickly. For example, it can happen that a patient is cheerful and mild one moment and then throws a tantrum the next. In this case, those affected often do not realize that they are sometimes hurting others around them, as their ability to empathize is no longer sufficiently developed due to the illness.

Compulsive behavior in Parkinson’s disease: shopping addiction, gambling addiction, sex addiction

These impulse control disorders – i.e. behaviors in which people cannot resist an inner urge – often represent a major psychological burden for those affected or their relatives. Compulsive excessive buying behavior, for example, can cause considerable financial damage and put an entire family in financial distress.

Around five percent of all Parkinson’s patients develop compulsive gambling behavior. This usually refers to excessive gambling, which can also lead to financial difficulties. Last but not least, inappropriate sexual behavior can also become apparent. Those affected make inappropriate advances due to the drug-induced, increased libido and impaired impulse control.

Cause of impulse control disorders

Parkinson’s medications such as levodopa generally help people with Parkinson’s to get the motor symptoms of the disease under control. However, Parkinson’s therapy with standard medication can also lead to exaggerated reactions caused by a sudden dopamine high, i.e. an excess of dopamine. This includes not only the euphoric episodes associated with the typical mood swings, but also the addictive behavior that occurs in some patients, for example a shopping addiction, gambling addiction or sex addiction.

Treatment of impulse control disorders

Impulse control disorders are treated by adjusting the medication, such as reducing the dose or administering an alternative Parkinson’s medication. In addition, cognitive behavioral therapy may also bring the desired success. In this therapy, those affected learn how they can better control their addictive behavior in order to avert impending dangers.

What else can you do if your personality changes?

In addition to correctly adjusted medication, a healthy and active lifestyle is important to improve the quality of life with Parkinson’s disease. The following measures may help to counteract changes in mood such as dementia or depression in Parkinson’s disease:

• Keep moving: Plan daily exercise, as this stimulates blood flow to the brain, strengthens your muscles, your cognitive performance and thus lifts your mood. You should do about 30 minutes of moderate exercise three times a week. Suitable activities include table tennis, dancing, Nordic walking, swimming, cycling or Qigong.
• Eat a healthy diet: Make sure you eat a high-fiber diet with whole grain products, plenty of vegetables, salad and fruit (organic if possible), vegetable oils, nuts, seeds, whole grain products, some poultry meat, fish and little sugar. A Mediterranean diet is ideal – read more about this in our article on a healthy diet for Parkinson’s.
• Drink enough: Drink about 1.5 liters of water or unsweetened tea a day so that the brain can work properly.
• Exercise your brain: Those affected should keep their brain fit – this can be achieved by solving puzzles, doing regular activities with friends or learning new activities such as painting, crafting or playing an instrument.

Tips for relatives on dealing with personality changes

Living alongside a person with Parkinson’s is not always easy for relatives – especially when personality changes are added to the motor problems as the disease progresses. Good support from family, friends and care staff is important so that those affected can continue to enjoy life. However, relatives also need to think about themselves so that they don’t burn out while providing care or support. We would like to share the following tips with you as a caregiver:

• Find out at an early stage which counseling services you can use if you have Parkinson’s.
• Get support from mobile assistance services, e.g. if you are planning a vacation or if you are overwhelmed by your care responsibilities.
• Find out about financial assistance within the framework of the care allowance.
• Try not to relate the outbursts of anger or other negative emotions to yourself. Realize that these are illness-related reactions that are not deliberate on the part of the sick person and have nothing to do with you.
• Involve the person with the illness in certain decisions. Because if you decide everything on your own due to the illness, the person affected will feel set back and no longer taken seriously. At the same time, they want to continue to be able to make their own decisions. However, if there is resistance to important matters such as personal hygiene, it makes sense for you to assert your opinion.
• Involve the person as much as possible in daily tasks such as peeling potatoes, despite their illness, so that they continue to feel needed and you are not alone with all the tasks.
• A self-help group for relatives of people with Parkinson’s can sometimes help you to cope better with the psychological strain. Here you can also get tips on how to deal with the person with the disease.
• Ask the neurologist treating your relative how you can help him or her in everyday life in a skillful and sensible way so that his or her independence is maintained as far as possible.

The personality changes that can occur with Parkinson’s are a challenge for those affected and their relatives. However, with patience, forbearance and the willingness to seek help as a family caregiver under certain circumstances and to allow themselves time to rest in between, relatives can provide good support for their family member with the disease.