Signs and symptoms of Parkinson's disease

Signs and Symptoms of Parkinson's Disease

Parkinson's disease (PD) is a long-term degenerative disorder of the central nervous system that mainly affects the motor system. The symptoms generally emerge slowly and, as the disease worsens, non-motor symptoms become more common. The most noticeable signs are related to movement, with non-motor symptoms also significantly affecting the quality of life. This article outlines the primary signs and symptoms associated with Parkinson's disease.

Histological sample of Substantia nigra in Parkinson's disease cropped

Motor Symptoms

The motor symptoms of Parkinson's disease are the most recognizable and can be categorized under the acronym TRAP: Tremor, Rigidity, Akinesia (or bradykinesia), and Postural instability.

Tremor

The tremor associated with Parkinson's disease has a characteristic appearance, often described as a "pill-rolling" tremor. It is a resting tremor, meaning it decreases during voluntary movement and increases when the limb is at rest. The tremor usually starts in one hand, but as the disease progresses, it may affect both sides of the body.

Rigidity

Muscular rigidity in PD patients presents as a uniform stiffness throughout the range of motion. This symptom is often identified through a physical examination and can affect any part of the body, leading to a decreased range of motion and discomfort.

Akinesia/Bradykinesia

Akinesia (lack of movement) or bradykinesia (slowness of movement) is a hallmark sign of Parkinson's disease. It manifests as a significant reduction in spontaneous movement, which can make everyday tasks difficult. This symptom is often one of the most disabling for PD patients, affecting their quality of life.

Postural Instability

Postural instability refers to a decreased ability to maintain upright posture and balance. It is a later symptom in the progression of Parkinson's disease and increases the risk of falls.

Non-Motor Symptoms

Non-motor symptoms of Parkinson's disease are diverse and can affect various aspects of a patient's life, including cognitive function, mood, sleep, and autonomic functions.

Cognitive Impairment

Cognitive changes in Parkinson's disease can range from mild cognitive impairment to Parkinson's disease dementia. Common cognitive deficits include problems with executive functions, attention, and memory.

Mood Disorders

Depression and anxiety are common in Parkinson's disease, affecting up to 50% of patients. These mood disorders can significantly impact the quality of life and may precede the diagnosis of PD.

Sleep Disturbances

Patients with Parkinson's disease often experience sleep disturbances, including insomnia, excessive daytime sleepiness, and REM sleep behavior disorder, where patients act out their dreams.

Autonomic Dysfunction

Autonomic symptoms can include orthostatic hypotension (a significant drop in blood pressure when standing), constipation, and urinary incontinence. These symptoms result from the autonomic nervous system's impaired regulation.

Diagnosis and Management

The diagnosis of Parkinson's disease is primarily clinical, based on medical history and a neurological examination. There is no definitive test for PD, but imaging studies like MRI and DAT scans can support the diagnosis. Management of Parkinson's disease is multidisciplinary, involving medication, physical therapy, and in some cases, surgical intervention.