Parkinson's Disease

Parkinson's Disease

  • Tuesday, May 30, 2017

Parkinson's disease (PD) was first described by the English doctor James Parkinson in 1871. It is a chronic and progressive neurological pathology which primarily affects body movements. PD is the second most common neurodegenerative condition after Alzheimer’s Disease.

PD typically affects one percent of people over the age of 60, and men are usually more affected than women. According to The Lancet Global Burden of Disease, 6.2 million people suffered PD in 2015 and the disease caused around 120.000 death globally. The average life expectancy following diagnosis is between 7 and 14 years.

PD’s initial signals manifest when performing daily tasks which require fine motor control, such as getting dressed or writing. Although symptoms vary from individuals to individuals, the most common ones include tremor of limbs and face, slowness of movement (bradykinesia), muscle stiffness, impaired balance and coordination. Cognitive difficulty, dementia, depression, anxiety, and emotional problems may also occur in the syndrome.

The cause of PD is unknown. It is generally accepted it involves both genetic and environmental factors. Around 15 percent of PD’s patients suffer a genetic variant of the pathology, in which a series of mutations in specific genes are involved.

PD leads to the malfunction and death of neurons in the area of the midbrain known as substantia nigra. Some of these neurons produce dopamine, a chemical substance which partially regulates and controls movement and coordination. As PD progresses, the production of dopamine decreases, eventually leading to a person’s losing control over his or her movements. PD is also considered a synucleiopathy, e.g., a neurodegenerative condition characterized by an abnormal accumulation of alpha-synuclein protein in the brain in the form of Lewy bodies. This is relevant because Lewy bodies are also found in the brain stem and the olfactory bulb, areas related to nonmotor functions such as sense of smell and sleep regulation which are also affected by PD.

There is no specific medical test to diagnose PD and some of its symptoms may overlap with those of other neurological conditions such as Alzheimer’s Disease. Magnetic resonance imaging and computed tomography are helpful in ruling out other diseases. Clinical studies oriented to determine the most accurate diagnosis of PD use scales of symptom progression

Although there is no cure for PD, some treatments help reduce symptoms and improve the patients’ quality of life, including medication, physiotherapy, physical exercise and, in some cases, brain surgery.

Researchers continue to explore factors involved in causing PD and what could help people preventing the developing of the disease. The main areas of research include stem cell transplants, neuroprotective vaccines, and gene therapy.