Changes in the brain could act as an early warning sign for Parkinson’s disease, years before physical symptoms of the condition begin, new research has revealed.
Scans of a small number of high-risk patients revealed that levels of the brain chemical serotonin begin to decline 20 years or more before tremors, speech problems or other typical symptoms start to occur.
The research team, from King's College London, now believe their findings could lead to new screening tools and treatments, following further, more large scale, studies.
According to the NHS Parkinson's is a neurological condition in which parts of the brain become progressively damaged over many years.
The condition is thought to affect around 1 in 500 people in the UK.
The NHS says the three main symptoms of Parkinson's disease are involuntary shaking (tremors), slow movement and stiff and inflexible muscles, but depression, memory problems and difficulty sleeping are also common.
Though there are treatments available to help reduce the main symptoms, there is currently no known cure of the disease.
Traditionally, the disease is thought to be linked to a chemical called dopamine, which is lacking in the brains of people with the condition.
“Dopamine plays a vital role in regulating the movement of the body. A reduction in dopamine is responsible for many of the symptoms of Parkinson's disease,” the NHS explains.
Most of the time Parkinson’s appears to have no known cause, so people affected by the disease are not studied before their symptoms appear.
But the research team at Kings College London, believe their findings, published in Lancet Neurology, suggest that changes in the brain’s serotonin levels could act as an early warning sign.
The researchers looked at the brains of 14 people from villages in southern Greece and Italy who all have rare mutations in the SNCA gene, making them almost certain to develop the disease.
Half the study group had already been diagnosed with Parkinson's and half had not yet shown any symptoms.
By comparing their brains with another 65 patients with Parkinson's and 25 healthy volunteers, the researchers were able to identify early changes in serotonin levels in patients in their 20s and 30s.
Commenting on the findings lead study author Professor Marios Politis, from the Institute of Psychiatry, Psychology and Neuroscience at King's, told BBC: "Our results suggest that early detection of changes in the serotonin system could open doors to the development of new therapies to slow, and ultimately prevent, progression of Parkinson's disease.”
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What is Parkinson’s Disease?
Dr Emer MacSweeney, Consultant Neuroradiologist at Re:Cognition Health says Parkinson's disease is a chronic neurological condition which is progressive, meaning the symptoms worsen over time.
Approximately 145,000 in the UK have a diagnosis of Parkinson's disease. The condition is slightly more common amongst men and is more common in older adults, however, it can also affect younger adults.
What Causes Parkinson's Disease?
“Much research is underway in the field of Parkinson's disease to determine why people develop this condition, as well as new treatments to help treat its symptoms,” explains Dr MacSweeney.
“It is thought that Parkinson's is caused by a combination of genetic and environmental factors. Essentially, people with Parkinson's disease don't have enough dopamine, a chemical which functions as a neurotransmitter which enables certain nerve cells to send essential signals to other nerve cells.
“Individuals presenting with Parkinson's Disease experience a loss of control of voluntary movements, which results from a loss of the nerve cells in the brain which make dopamine,” she adds.
Getting a diagnosis of Parkinson's disease
According to Dr MacSweeney, currently getting diagnosed can be quite a complex process, as symptoms vary from person to person and many illnesses can imitate the symptoms of Parkinson's disease.
That’s why this latest discovery in potential early indicators of brain changes could be so beneficial.
“As with all neurological conditions, an early diagnosis is essential to enable the very best treatment and to help manage the symptoms, especially as they progress,” explains Dr MacSweeney.
“Speech therapy, exercise, physiotherapy and occupational therapy are some of the therapy options that can help individuals manage symptoms of Parkinson's disease.”
What are the early signs of Parkinson's disease?
“Motor symptoms such as muscle rigidity, tremors, involuntary shaking and slowness of movement are all early signs of the disease and symptoms often start on one side of the body,” says Dr MacSweeney.
Other key signs of Parkinson's include:
• Problems with balance
• A change in facial expressions which may include prolonged staring, lack of blinking
• Discomfort, numbness, tingling or pain in the limbs and neck
• Frozen or painful shoulder
• Limping or dragging the leg when walking or a shuffling gait
• Not swinging one arm when walking
• A softening of the voice, slurred speech and problems swallowing
• Decreased sense of smell
• Poor posture which may include stooping
• Small handwriting
Mental health and Parkinson's disease
“Depression, anxiety, hallucinations and memory problems are some of the mental health conditions that can be experienced by those with Parkinson's disease,” explains Dr MacSweeney.
“They also have an increased risk of developing Parkinson's disease dementia which accounts for approximately 2% of dementia cases in the UK.”
It is imperative that individuals who have mental health concerns seek medical advice to help manage and treat their symptoms.