Signs And Symptoms Of Parkinson's Disease
   HOME

TheInfoList



OR:

Signs and symptoms of Parkinson's disease are varied.
Parkinson's disease Parkinson's disease (PD), or simply Parkinson's, is a neurodegenerative disease primarily of the central nervous system, affecting both motor system, motor and non-motor systems. Symptoms typically develop gradually and non-motor issues become ...
affects movement, producing motor
symptom Signs and symptoms are diagnostic indications of an illness, injury, or condition. Signs are objective and externally observable; symptoms are a person's reported subjective experiences. A sign for example may be a higher or lower temperature ...
s. Non-motor symptoms, which include
dysautonomia Dysautonomia, autonomic failure, or autonomic dysfunction is a condition in which the autonomic nervous system (ANS) does not work properly. This condition may affect the functioning of the heart, bladder, intestines, sweat glands, pupils, and ...
, cognitive and neurobehavioral problems, and sensory and sleep difficulties, are also common. When other diseases mimic Parkinson's disease, they are categorized as
parkinsonism Parkinsonism is a clinical syndrome characterized by tremor, bradykinesia (slowed movements), Rigidity (neurology), rigidity, and balance disorder, postural instability. Both hypokinetic features (bradykinesia and akinesia) and hyperkinetic f ...
.


Motor

Four motor symptoms are considered
cardinal signs Signs and symptoms are diagnostic indications of an illness, injury, or condition. Signs are objective and externally observable; symptoms are a person's reported subjective experiences. A sign for example may be a higher or lower temperature ...
in PD: slowness of movement (
bradykinesia Hypokinesia is one of the classifications of movement disorders, and refers to decreased bodily movement. Hypokinesia is characterized by a partial or complete loss of muscle movement due to a disruption in the basal ganglia. Hypokinesia is a sy ...
), tremor, rigidity, and postural instability. Typical for PD is an initial asymmetric distribution of these symptoms, where in the course of the disease, a gradual progression to bilateral symptoms develops, although some asymmetry usually persists. Other motor symptoms include gait and posture disturbances such as decreased arm swing, a forward-flexed posture, and the use of small steps when walking; speech and swallowing disturbances; and other symptoms such as a mask-like facial expression or small handwriting are examples of the range of common motor problems that can appear.


Cardinal signs

Four motor signs are considered cardinal in PD:
tremor A tremor is an involuntary, somewhat rhythmic muscle contraction and relaxation involving neural oscillations, oscillations or twitching movements of one or more body parts. It is the most common of all involuntary movements and can affect the h ...
, rigidity,
bradykinesia Hypokinesia is one of the classifications of movement disorders, and refers to decreased bodily movement. Hypokinesia is characterized by a partial or complete loss of muscle movement due to a disruption in the basal ganglia. Hypokinesia is a sy ...
, and
postural instability A balance disorder is a disturbance that causes an individual to feel unsteady, for example when standing or walking. It may be accompanied by feelings of giddiness, or wooziness, or having a sensation of movement, spinning, or floating. Balance ...
(also referred to as parkinsonism). *
Tremor A tremor is an involuntary, somewhat rhythmic muscle contraction and relaxation involving neural oscillations, oscillations or twitching movements of one or more body parts. It is the most common of all involuntary movements and can affect the h ...
is the most apparent and well-known sign. It is also the most common; though around 30% of individuals with PD do not have tremor at disease onset, most develop it as the disease progresses. It is usually a rest tremor, maximal when the limb is at rest and disappearing with voluntary movement and sleep. It affects to a greater extent the most
distal Standard anatomical terms of location are used to describe unambiguously the anatomy of humans and other animals. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position provi ...
part of the limb, and at onset typically appears in only a single arm or leg, becoming bilateral later during the course of the disease. Frequency of PD tremor is between 4 and 6
hertz The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), often described as being equivalent to one event (or Cycle per second, cycle) per second. The hertz is an SI derived unit whose formal expression in ter ...
(cycles per second). It is a
pronation Motion, the process of movement, is described using specific anatomical terminology, anatomical terms. Motion includes movement of Organ (anatomy), organs, joints, Limb (anatomy), limbs, and specific sections of the body. The terminology used de ...
supination Motion, the process of movement, is described using specific anatomical terms. Motion includes movement of organs, joints, limbs, and specific sections of the body. The terminology used describes this motion according to its direction relativ ...
tremor that is described as "pill-rolling"; that is, the index finger of the hand tends to get into contact with the thumb, and they perform a circular movement together. Such term was given due to the similarity of the movement in PD patients with the former pharmaceutical technique of manually making pills. PD tremor is not improved with alcohol intake, as opposed to
essential tremor Essential tremor (ET), also called benign tremor, familial tremor, and idiopathic tremor, is a medical condition characterized by involuntary rhythmic contractions and relaxations ( oscillations or twitching movements) of certain muscle groups i ...
. * Rigidity is characterized by an increased
muscle tone In physiology, medicine, and anatomy, muscle tone (residual muscle tension or tonus) is the continuous and passive partial contraction of the muscles, or the muscle's resistance to passive stretch during resting state.O’Sullivan, S. B. (2007) ...
(an excessive and continuous contraction of the muscles) which produces
stiffness Stiffness is the extent to which an object resists deformation in response to an applied force. The complementary concept is flexibility or pliability: the more flexible an object is, the less stiff it is. Calculations The stiffness, k, of a ...
and resistance to movement in joints. Rigidity may be associated with joint pain, with such pain being a frequent initial manifestation of the disease. When limbs of the person with PD are passively moved by others, a "
cogwheel A gear or gearwheel is a rotating machine part typically used to transmit rotational motion and/or torque by means of a series of teeth that engage with compatible teeth of another gear or other part. The teeth can be integral saliences or ...
rigidity" is commonly seen. Cogwheel-like or ratchety jerks are characterized by the articulation moving as opposed to the normal fluid movement; when a muscle is externally tried to move, it resists at first, but with enough force, it is partially moved until it resists again, and only with further force, will it be moved. The combination of tremor and increased tone is considered to be at the origin of cogwheel rigidity. *
Bradykinesia Hypokinesia is one of the classifications of movement disorders, and refers to decreased bodily movement. Hypokinesia is characterized by a partial or complete loss of muscle movement due to a disruption in the basal ganglia. Hypokinesia is a sy ...
and akinesia: the former is slowness of movement, while the latter is the absence of it. It is the most characteristic clinical feature of PD, and is associated with difficulties along the whole course of the movement process, from planning to initiation and finally execution of a movement. The performance of sequential and simultaneous movements is also hindered. Bradykinesia is the most disabling symptom in the early stages of the disease. Initial manifestations of bradykinesia are problems when performing daily life tasks requiring fine motor control such as writing, sewing, or getting dressed. Clinical evaluation is based in similar tasks consisting such as alternating movements between both hands or feet. Bradykinesia is not equal for all movements or times. It is modified by the activity or emotional state of the subject to the point of some patients who are barely able to walk being capable of riding a bicycle. Generally, patients have less difficulties when some sort of external cue is provided. *
Postural instability A balance disorder is a disturbance that causes an individual to feel unsteady, for example when standing or walking. It may be accompanied by feelings of giddiness, or wooziness, or having a sensation of movement, spinning, or floating. Balance ...
: In the late stages, postural instability is typical, which leads to impaired balance and frequent falls, and secondarily to bone fractures. Instability is often absent in the initial stages, especially in younger people. Up to 40% of the patients may experience falls and around 10% may have falls weekly, with the number of falls being related to the severity of PD. It is produced by a failure of postural
reflexes In biology, a reflex, or reflex action, is an involuntary, unplanned sequence or action and nearly instantaneous response to a Stimulus (physiology), stimulus. Reflexes are found with varying levels of complexity in organisms with a nervous s ...
, along other disease-related factors such as
orthostatic hypotension Orthostatic hypotension, also known as postural hypotension, is a medical condition wherein a person's blood pressure drops when they are standing up ( orthostasis) or sitting down. Primary orthostatic hypotension is also often referred to as ne ...
or
cognitive Cognition is the "mental action or process of acquiring knowledge and understanding through thought, experience, and the senses". It encompasses all aspects of intellectual functions and processes such as: perception, attention, thought, ...
and sensory changes.


Other motor symptoms

Other motor symptoms include: *
Gait Gait is the pattern of Motion (physics), movement of the limb (anatomy), limbs of animals, including Gait (human), humans, during Animal locomotion, locomotion over a solid substrate. Most animals use a variety of gaits, selecting gait based on s ...
and posture disturbances: **Shuffling gait is characterized by short steps, with feet barely leaving the ground. Small obstacles tend to cause the patient to trip. **Decreased arm-swing **Turning en bloc'', rather than the usual twisting of the neck and trunk and pivoting on the toes, is when PD patients keep their necks and trunks rigid, requiring multiple small steps to accomplish a turn. ** Camptocormia is a stooped, forward-flexed posture. In severe forms, the head and upper shoulders may be bent at a
right angle In geometry and trigonometry, a right angle is an angle of exactly 90 Degree (angle), degrees or radians corresponding to a quarter turn (geometry), turn. If a Line (mathematics)#Ray, ray is placed so that its endpoint is on a line and the ad ...
relative to the trunk. ** Festination is a combination of stooped posture, imbalance, and short steps. It leads to a gait that gets progressively faster and faster, often ending in a fall. ** Gait freezing, also called motor blocks, is a manifestation of akinesia. Gait freezing is characterized by a sudden inability to move the lower extremities which usually lasts less than 10 seconds. It may worsen in tight, cluttered spaces, when attempting to initiate gait or turning around, or when approaching a destination. Freezing improves with treatment and also with behavioral techniques such as marching to command or following a given rhythm. **
Dystonia Dystonia is a neurology, neurological Hyperkinesia, hyperkinetic Movement disorders, movement disorder in which sustained or repetitive muscle contractions occur involuntarily, resulting in twisting and repetitive movements or abnormal fixed po ...
is abnormal, sustained, sometimes painful twisting muscle contractions, often affecting the foot and ankle (mainly toe flexion and foot inversion), which often interferes with gait. **
Scoliosis Scoliosis (: scolioses) is a condition in which a person's Vertebral column, spine has an irregular curve in the coronal plane. The curve is usually S- or C-shaped over three dimensions. In some, the degree of curve is stable, while in others ...
is abnormal curvature of the spine. *Speech and swallowing disturbances: ** Hypophonia (soft speech). **Monotonic speech—quality tends to be soft, hoarse, and monotonous. **Festinating speech—excessively rapid, soft, poorly intelligible speech. ** Drooling is most likely caused by a weak, infrequent swallow. **
Dysphagia Dysphagia is difficulty in swallowing. Although classified under " symptoms and signs" in ICD-10, in some contexts it is classified as a condition in its own right. It may be a sensation that suggests difficulty in the passage of solids or l ...
is an impaired ability to swallow, which in the case of PD is probably related to an inability to initiate the swallowing reflex or by a too long laryngeal or oesophageal movement. It can lead to
aspiration pneumonia Aspiration pneumonia is a type of lung infection that is due to a relatively large amount of material from the stomach or mouth entering the lungs. Signs and symptoms often include fever and cough of relatively rapid onset. Complications may incl ...
. **
Dysarthria Dysarthria is a speech sound disorder resulting from neurological injury of the motor component of the motor–speech system and is characterized by poor articulation of phonemes. It is a condition in which problems effectively occur with the ...
is a form of speech disorder. *Other motor symptoms and signs: **
Fatigue Fatigue is a state of tiredness (which is not sleepiness), exhaustion or loss of energy. It is a signs and symptoms, symptom of any of various diseases; it is not a disease in itself. Fatigue (in the medical sense) is sometimes associated wit ...
** Hypomimia (a mask-like face). **Difficulty rolling in bed or rising from a seated position. **
Micrographia ''Micrographia: or Some Physiological Descriptions of Minute Bodies Made by Magnifying Glasses. With Observations and Inquiries Thereupon'' is a historically significant book by Robert Hooke about his observations through various lenses. It wa ...
(small, cramped handwriting). **Impaired fine-motor dexterity and
motor coordination In physiology, motor coordination is the orchestrated movement of multiple body parts as required to accomplish intended actions, like walking. This coordination is achieved by adjusting kinematic and kinetic parameters associated with each bo ...
**Impaired gross-motor coordination. **
Akathisia Akathisia (IPA: /æ.kə.ˈθɪ.si.ə/) is a movement disorder characterized by a subjective feeling of inner restlessness accompanied by mental distress and/or an inability to sit still. Usually, the legs are most prominently affected. Those a ...
(an unpleasant desire to move, often related to medication). **Reemergence of
primitive reflexes Primitive reflexes are reflex actions originating in the central nervous system that are exhibited by normal infants, but not neurologically intact adults, in response to particular stimuli. These reflexes are suppressed by the development of th ...
. **
Glabellar reflex The glabellar reflex, also known as the "glabellar tap sign", is a primitive reflex elicited by repetitive tapping of the the smooth part of the forehead above the nose and between the eyebrows. Subjects respond to the first several taps by blink ...


Neuropsychiatric

Parkinson's disease causes neuropsychiatric disturbances, which mainly include
cognitive disorder Neurocognitive disorders (NCDs), also known as cognitive disorders (CDs), are a category of mental health disorders that primarily affect cognitive abilities including learning, memory, perception, and problem-solving. Neurocognitive disorders in ...
s,
mood disorder A mood disorder, also known as an affective disorder, is any of a group of conditions of mental and behavioral disorder where the main underlying characteristic is a disturbance in the person's mood. The classification is in the ''Diagnostic ...
s, and behavior problems, and can be as disabling as motor symptoms. Since
L-Dopa -DOPA, also known as -3,4-dihydroxyphenylalanine and used medically as levodopa, is made and used as part of the normal biology of some plants and animals, including humans. Humans, as well as a portion of the other animals that utilize -DO ...
, the widely used drug in Parkinson's disease treatment, is decarboxylated by
aromatic L-amino acid decarboxylase Aromatic L-amino acid decarboxylase (AADC or AAAD), also known as DOPA decarboxylase (DDC), tryptophan decarboxylase, and 5-hydroxytryptophan decarboxylase, is a lyase enzyme (), located in region 7p12.2-p12.1. Mechanism The enzyme uses pyri ...
(AADC), which is found in both
dopaminergic Dopaminergic means "related to dopamine" (literally, "working on dopamine"), a common neurotransmitter. Dopaminergic substances or actions increase dopamine-related activity in the brain. Dopaminergic pathways, Dopaminergic brain pathways facil ...
and serotonergic neurons, it is possible for serotonergic neurons to convert L-Dopa into
dopamine Dopamine (DA, a contraction of 3,4-dihydroxyphenethylamine) is a neuromodulatory molecule that plays several important roles in cells. It is an organic chemical of the catecholamine and phenethylamine families. It is an amine synthesized ...
and generate excessive neuronal death by creating
reactive oxygen species In chemistry and biology, reactive oxygen species (ROS) are highly Reactivity (chemistry), reactive chemicals formed from diatomic oxygen (), water, and hydrogen peroxide. Some prominent ROS are hydroperoxide (H2O2), superoxide (O2−), hydroxyl ...
and quinoproteins. The association of
serotonin Serotonin (), also known as 5-hydroxytryptamine (5-HT), is a monoamine neurotransmitter with a wide range of functions in both the central nervous system (CNS) and also peripheral tissues. It is involved in mood, cognition, reward, learning, ...
with mood and cognition may explain some of the side-effects observed in patients treated with L-Dopa due to serotonin deficit. In most cases, motor symptoms predominate at early PD stages, while cognitive disturbances (such as mild cognitive impairment or
dementia Dementia is a syndrome associated with many neurodegenerative diseases, characterized by a general decline in cognitive abilities that affects a person's ability to perform activities of daily living, everyday activities. This typically invo ...
) emerge later. The onset of parkinsonism in PD relative to dementia is used as an arbitrary criterion to clinically distinguish Parkinson's disease dementia (PDD) and
dementia with Lewy bodies Dementia with Lewy bodies (DLB) is a type of dementia characterized by changes in sleep, behavior change (individual), behavior, cognition, movement, and dysautonomia, regulation of automatic bodily functions. Unlike some other dementias, mem ...
(DLB) using a 'one-year rule'. Dementia onset within 12-months of or at the same time as motor dysfunctions qualified as DLB, whereas in PDD, parkinsonism had to precede dementia by at least one year. Cognitive disturbances occur even in the initial stages of the disease in some cases. A very high proportion of patients have mild cognitive impairment as the disease advances. Most common deficits in nondemented patients are: *
Executive dysfunction In psychology and neuroscience, executive dysfunction, or executive function deficit, is a disruption to the efficacy of the executive functions, which is a group of cognitive processes that regulate, control, and manage other cognitive processe ...
, which translates into impaired set shifting, poor
problem solving Problem solving is the process of achieving a goal by overcoming obstacles, a frequent part of most activities. Problems in need of solutions range from simple personal tasks (e.g. how to turn on an appliance) to complex issues in business an ...
, and fluctuations in
attention Attention or focus, is the concentration of awareness on some phenomenon to the exclusion of other stimuli. It is the selective concentration on discrete information, either subjectively or objectively. William James (1890) wrote that "Atte ...
among other difficulties * Slowed cognitive speed (bradyphrenia) *Memory problems can occur, specifically in recalling learned information, with an important improvement with cues.
Recognition memory Recognition memory, a subcategory of explicit memory, is the ability to recognize previously encountered events, objects, or people.Medina, J. J. (2008)The biology of recognition memory. ''Psychiatric Times''. When the previously experienced event ...
is less impaired than
free recall Free recall is a common task in the psychological study of memory. In this task, participants study a list of items on each trial, and then are prompted to recall the items in any order. Items are usually presented one at a time for a short du ...
, pointing towards a retrieving more than to an encoding problem. *Regarding language, patients are found to have problems in verbal fluency tests. * Visuospatial skills difficulties, which are seen when the person with PD is for example asked to perform tests of
face perception Facial perception is an individual's understanding and interpretation of the face. Here, perception implies the presence of consciousness and hence excludes automated facial recognition systems. Although facial recognition is found in other spe ...
and perception of line orientation. Deficits tend to aggravate with time, developing in many cases into
dementia Dementia is a syndrome associated with many neurodegenerative diseases, characterized by a general decline in cognitive abilities that affects a person's ability to perform activities of daily living, everyday activities. This typically invo ...
. A person with PD has a six-fold increased risk of developing it, and the overall rate in people with the disease is around 30%. Moreover, prevalence of dementia increases in relation to disease duration, going up to 80%. Dementia has been associated with a reduced
quality of life Quality of life (QOL) is defined by the World Health Organization as "an individual's perception of their position in life in the context of the culture and value systems in which they live and in relation to their goals, expectations, standards ...
in patients and
caregiver A caregiver, carer or support worker is a paid or unpaid person who helps an individual with activities of daily living. Caregivers who are members of a care recipient's family or social network, who may have specific professional training, are o ...
s, increased mortality, and a higher probability of moving to a
nursing home A nursing home is a facility for the residential care of older people, senior citizens, or disabled people. Nursing homes may also be referred to as care homes, skilled nursing facilities (SNF), or long-term care facilities. Often, these terms ...
. Cognitive problems and dementia are usually accompanied by behavior and mood alterations, although these kinds of changes are also more common in those patients without cognitive impairment than in the general population. Most frequent mood difficulties include: * Depression is well recognized in PD, having been identified as "melancholia" by James Parkinson in his original report of the disease in 1817. Estimated prevalence rates of depression vary widely according to the population sampled and methodology used, although depressive symptoms, irrespective of classically defined DSM criteria for depression, are present in 35% of patients There is an increased risk for any individual with depression to go on to develop Parkinson's disease at a later date. It is increasingly thought to be a consequence of the disease rather than an emotional reaction to disability, although ample evidence shows that the relationship between depression and PD is bidirectional. General risk factors for depression are actually stronger markers for depression in PD patients than PD specific factors. Since Parkinson's affects many areas of the brain that control mood (specifically the
frontal lobe The frontal lobe is the largest of the four major lobes of the brain in mammals, and is located at the front of each cerebral hemisphere (in front of the parietal lobe and the temporal lobe). It is parted from the parietal lobe by a Sulcus (neur ...
as well as those areas that produce
serotonin Serotonin (), also known as 5-hydroxytryptamine (5-HT), is a monoamine neurotransmitter with a wide range of functions in both the central nervous system (CNS) and also peripheral tissues. It is involved in mood, cognition, reward, learning, ...
,
norepinephrine Norepinephrine (NE), also called noradrenaline (NA) or noradrenalin, is an organic compound, organic chemical in the catecholamine family that functions in the brain and human body, body as a hormone, neurotransmitter and neuromodulator. The ...
and
dopamine Dopamine (DA, a contraction of 3,4-dihydroxyphenethylamine) is a neuromodulatory molecule that plays several important roles in cells. It is an organic chemical of the catecholamine and phenethylamine families. It is an amine synthesized ...
), depression may result. Depression is one of the most common neuropsychiatric conditions found in patients who have PD, and it is associated with more rapid progression of physical symptoms and a greater decline in cognitive skills. Depression in patients with PD was found to be more predictive of overall disability than was the motor disability from the PD. An interesting finding is that although a high rate of depression is seen in patients with PD, the incidence of suicide is lower in this group of patients. Many of the symptoms of PD may overlap with those of depression, making diagnosis a difficult issue. *
Apathy Apathy, also referred to as indifference, is a lack of feeling, emotion, interest, or concern about something. It is a state of indifference, or the suppression of emotions such as concern, excitement, motivation, or passion. An apathetic i ...
*
Anxiety Anxiety is an emotion characterised by an unpleasant state of inner wikt:turmoil, turmoil and includes feelings of dread over Anticipation, anticipated events. Anxiety is different from fear in that fear is defined as the emotional response ...
is seen; 70% of individuals with PD diagnosed with pre-existing depression go on to develop anxiety. About 90% of PD patients with pre-existing anxiety subsequently develop depression,
apathy Apathy, also referred to as indifference, is a lack of feeling, emotion, interest, or concern about something. It is a state of indifference, or the suppression of emotions such as concern, excitement, motivation, or passion. An apathetic i ...
, or
abulia In neurology, abulia, or aboulia (from , meaning "will"),Bailly, A. (2000). Dictionnaire Grec Français, Éditions Hachette. refers to a lack of will or initiative and can be seen as a disorder of diminished motivation. Abulia falls in the midd ...
. Obsessive–compulsive behaviors (also known as
impulse-control disorder Impulse-control disorder (ICD) is a class of psychiatric disorders characterized by impulsivity – failure to resist a temptation, an urge, or an impulse; or having the inability to not speak on a thought. The fifth edition of the American Ps ...
s) such as craving,
binge eating Binge eating is a pattern of disordered eating which consists of episodes of uncontrollable eating. It is a common symptom of eating disorders such as binge eating disorder and bulimia nervosa. During such binges, a person rapidly consumes an exc ...
,
hypersexuality Hypersexuality is a proposed medical condition said to cause unwanted or excessive sexual arousal, causing people to engage in or think about sexual activity to a point of distress or impairment., according to the website of ''Psychology Toda ...
, pathological gambling,
punding Punding is compulsive performance of repetitive, mechanical tasks, such as assembling and disassembling, collecting, or sorting objects. It can also apply to digital objects, such as computer files and data. The term was originally coined to desc ...
, or others, can also appear in PD, and have been related to a dopamine dysregulation syndrome associated with the medications for the disease. Psychotic symptoms are common in PD, generally associated with dopamine therapy. Symptoms of psychosis, or impaired reality testing, are either
hallucination A hallucination is a perception in the absence of an external stimulus that has the compelling sense of reality. They are distinguishable from several related phenomena, such as dreaming ( REM sleep), which does not involve wakefulness; pse ...
s, typically visual, less commonly auditory, and rarely in other domains including tactile, gustatory, or olfactory, or
delusion A delusion is a fixed belief that is not amenable to change in light of conflicting evidence. As a pathology, it is distinct from a belief based on false or incomplete information, confabulation, dogma, illusion, hallucination, or some other m ...
s, that is, irrational beliefs. Hallucinations are generally stereotyped and without emotional content. Initially, patients usually have insight so that the hallucinations are benign in terms of their immediate impact, but have poor prognostic implications, with increased risk of dementia, worsened psychotic symptoms, and mortality. Delusions occur in about 5-10% of treated patients, and are considerably more disruptive, being paranoid in nature, of spousal infidelity or family abandonment. Psychosis is an independent risk factor for nursing-home placement. Hallucinations can occur in parkinsonian syndromes for a variety of reasons. An overlap exists between PD and
dementia with Lewy bodies Dementia with Lewy bodies (DLB) is a type of dementia characterized by changes in sleep, behavior change (individual), behavior, cognition, movement, and dysautonomia, regulation of automatic bodily functions. Unlike some other dementias, mem ...
, so that where Lewy bodies are present in the
visual cortex The visual cortex of the brain is the area of the cerebral cortex that processes visual information. It is located in the occipital lobe. Sensory input originating from the eyes travels through the lateral geniculate nucleus in the thalam ...
, hallucinations may result. Hallucinations can also be brought about by excessive dopaminergic stimulation. Most hallucinations are visual in nature, often formed as familiar people or animals, and are generally not threatening in nature. Some patients find them comforting; however, their caregivers often find this part of the disease most disturbing, and the occurrence of hallucinations is a major risk factor for hospitalisation. Treatment options consist of modifying the dosage of dopaminergic drugs taken each day, adding an
antipsychotic Antipsychotics, previously known as neuroleptics and major tranquilizers, are a class of Psychiatric medication, psychotropic medication primarily used to manage psychosis (including delusions, hallucinations, paranoia or disordered thought), p ...
drug such as quetiapine, or offering caregivers a psychosocial intervention to help them cope with the hallucinations.


Sleep

Sleep problems can be worsened by medications for PD, but they are a core feature of the disease. Sleep dysfunction in PD has significant negative impacts on both patient and carer quality of life. Some common symptoms are: *Excessive daytime
somnolence Somnolence (alternatively sleepiness or drowsiness) is a state of strong desire for sleep, or sleeping for unusually long periods (compare hypersomnia). It has distinct meanings and causes. It can refer to the usual state preceding falling aslee ...
*
Insomnia Insomnia, also known as sleeplessness, is a sleep disorder where people have difficulty sleeping. They may have difficulty falling asleep, or staying asleep for as long as desired. Insomnia is typically followed by daytime sleepiness, low ene ...
, characterized mostly by sleep fragmentation *Disturbances in
rapid eye movement sleep Rapid eye movement sleep (REM sleep or REMS) is a unique phase of sleep in mammals (including humans) and birds, characterized by random rapid movement of the eyes, accompanied by low muscle tone throughout the body, and the propensity of the s ...
: disturbingly vivid dreams, and rapid eye movement behavior disorder, characterized by acting out of dream content: It appears in a third of the patients and it is a risk factor for PD in the overall population.


Perception

*Impaired
proprioception Proprioception ( ) is the sense of self-movement, force, and body position. Proprioception is mediated by proprioceptors, a type of sensory receptor, located within muscles, tendons, and joints. Most animals possess multiple subtypes of propri ...
(the awareness of bodily position in three-dimensional space) *Reduction or loss of sense of smell (
hyposmia Hyposmia, or microsmia, is a reduced ability to smell and to detect odors. A related condition is anosmia, in which no odors can be detected. Some of the causes of olfaction problems are allergies, nasal polyps, viral infections and head trauma. ...
or
anosmia Anosmia, also known as smell blindness, is the lack of ability to detect one or more smells. Anosmia may be temporary or permanent. It differs from hyposmia, which is a decreased sensitivity to some or all smells. Anosmia can be categorized int ...
) may be an early marker of the disease. *
Paresthesias Paresthesia is a sensation of the skin that may feel like numbness (''hypoesthesia''), tingling, pricking, chilling, or burning. It can be temporary or chronic and has many possible underlying causes. Paresthesia is usually painless and can oc ...


Autonomic

*
Orthostatic hypotension Orthostatic hypotension, also known as postural hypotension, is a medical condition wherein a person's blood pressure drops when they are standing up ( orthostasis) or sitting down. Primary orthostatic hypotension is also often referred to as ne ...
leading to
dizziness Dizziness is an imprecise term that can refer to a sense of disorientation in space, vertigo, or lightheadedness. It can also refer to Balance disorder, disequilibrium or a non-specific feeling, such as giddiness or foolishness. Dizziness is a ...
and fainting *Oily skin *
Urinary incontinence Urinary incontinence (UI), also known as involuntary urination, is any uncontrolled leakage of urine. It is a common and distressing problem, which may have a significant effect on quality of life. Urinary incontinence is common in older women ...
(typically in later disease progression) and
nocturia Nocturia is defined by the International Continence Society (ICS) as "the complaint that the individual has to wake at night one or more times for voiding (''i.e., to urinate'')". The term is derived from Latin ''nox'' – "night", and Greek '' ...
(getting up in the night to pass urine) * Altered sexual function is characterized by profound impairment of sexual arousal, behavior, orgasm, and drive, and is found in mid- and late PD. * Excessive sweating


Gastrointestinal

Parkinson's Disease causes
constipation Constipation is a bowel dysfunction that makes bowel movements infrequent or hard to pass. The Human feces, stool is often hard and dry. Other symptoms may include abdominal pain, bloating, and feeling as if one has not completely passed the ...
and gastric dysmotility that is severe enough to endanger comfort and even health. A factor in this is the appearance of Lewy bodies and Lewy neurites even before these affect the functioning of the substantia nigra in the neurons in the
enteric nervous system The enteric nervous system (ENS) is one of the three divisions of the autonomic nervous system (ANS), the others being the sympathetic nervous system (SNS) and parasympathetic nervous system (PSNS). It consists of a mesh-like system of neurons th ...
that control gut functions.


Neuro-ophthalmological

PD is related to different
ophthalmological Ophthalmology (, ) is the branch of medicine that deals with the diagnosis, treatment, and surgery of eye diseases and disorders. An ophthalmologist is a physician who undergoes subspecialty training in medical and surgical eye care. Following a ...
abnormalities produced by the neurological changes. Among them are: *Decreased
blink Blinking is a bodily function; it is a semi-autonomic rapid closing of the eyelid. A single blink is determined by the forceful closing of the eyelid or inactivation of the levator palpebrae superioris and the activation of the palpebral por ...
rate *Irritation of the eye surface *Alteration in the tear film *Visual hallucinations * Decreased eye convergence *
Blepharospasm Blepharospasm is a neurological disorder characterized by intermittent, involuntary spasms and contractions of the orbicularis oculi muscle, orbicularis oculi (eyelid) muscles around both eyes. These result in abnormal twitching or blinking, an ...
*Abnormalities in ocular pursuit, ocular fixation and saccadic movements *Difficulties opening the eyelids This can have particular relevance when driving. People with Parkinson's have been shown to be less accurate in spotting landmarks and roadsigns whilst driving. *Limitations in upward gaze *
Blurred vision Blurred vision is an ocular symptom where vision becomes less precise and there is added difficulty to resolve fine details. Temporary blurred vision may involve dry eyes, eye infections, alcohol poisoning, hypoglycemia, or low blood pressur ...
*
Diplopia Diplopia is the simultaneous perception of two images of a single object that may be displaced in relation to each other. Also called double vision, it is a loss of visual focus under regular conditions, and is often voluntary. However, when occ ...
(double vision), produced by a reduced eye convergence.


References

{{Reflist, 30em Parkinson's disease