Parkinson’s Disease (PD) is the fastest growing neurological condition with over 6 million people worldwide affected by Parkinson’s – the total number of sufferers has more than doubled since 1990 cementing PD as one of the greatest challenges we face in healthcare today.
The prevalence is expected to dramatically rise over the course of the next twenty years as our population continues to age. In the US alone, the economic burden of Parkinson’s was $51.9 billion in 2017, and is forecasted to reach $79 billion by 2037. (1)
Parkinson’s is primarily a movement disorder and can lead to slowness (bradykinesia), tremor, rigidity (stiffness), and walking and balance problems. Other, non-movement symptoms include depression, memory problems, and sleep disorders. Parkinson’s is a lifelong, progressive neurodegenerative disease, meaning that symptoms worsen over time. The average age on onset is between 50 to 60 years of age. (2)
The disease is characterized by a loss or degeneration of dopamine-producing neurons in the brain, specifically in the region of the brain responsible for motor control (control of our movements). The exact underlying cause is not yet known, although there are a number of recognized risk factors. The diagnosis of Parkinson’s is based on clinical signs and symptoms. Early signs of the disease can be subtle which makes an early diagnosis of Parkinson’s difficult.
Once diagnosed, most people will begin taking medication when their symptoms begin to interfere with their everyday life and prevent them from carrying out everyday tasks. Most medications target the lack of dopamine in the brain e.g., Levodopa. The medications aim to ease the symptoms of slowness, stiffness and tremor and improve the quality of life however, they can also have intolerable side effects, especially at higher drug doses. Surgical therapies such as deep brain stimulation and continuous dopamine infusions can help but they come with major risks and have so far only proven mildly effective.
Exercise and physical activity have been shown to reduce the symptoms of PD. Physiotherapists play a large role in the management of some of the symptoms and can help create strategies for everyday living, exercising, and maintaining independence.
What are the challenges?
Parkinson’s disease can have a major impact on the individual and those around them. There is a myriad of challenges and frustrations that Parkinson’s patients face on a day-to-day basis. The experience of living with a diagnosis of Parkinson’s is unique to each person, however there are some symptoms and features which commonly affect a large number of sufferers.
Resting tremor is a type of shaking that can occur in the hands or the limbs of people with PD. This tremor can make it difficult to perform simple everyday tasks such as eating, getting dressed and brushing your teeth. Although medication can alleviate the resting tremor, the reality is that most Parkinson’s patients live with tremor to some degree, and this has a major impact on their quality of life.
Freezing of gait is when a person with Parkinson’s is suddenly unable to walk or move forward with their feet, despite the intention to walk. It feels like their feet are stuck to the ground. It can be one of the most debilitating symptoms of PD and can lead to falls and a loss of independence. (3) Falls alone are the most common cause of death from injury in the over 65s and the number one factor for a person to lose independence and go into long-term care. Falls have a significant economic burden, costing the NHS over £2 billion a year. (4)
Many people with PD experience fluctuations in their ability to move, this is commonly referred to as “on-off” times. When the medications are working in the correct, therapeutic range, control of movements are good, and this is referred to as “on” time. As the medications begin to wear off suddenly movements can become slow and difficult, and this is referred to as “off” time. If the dose of the medication is too high, intolerable side effects emerge. Tailoring the drug dose to each individual patient is difficult and the clinician relies on the patients reporting their symptoms over time in order to adjust the drug dose. Monitoring the symptoms over time and getting the right drug dose is a major challenge.
Making an early diagnosis of PD would be clinically beneficial because the medications are more effective in the early stages of the disease and early exercise and physical therapy has been shown to improve symptoms. However, diagnosing PD in its early stages is difficult due to the early signs and symptoms being subtle and due to the fact that there isn’t yet a diagnostic biomarker.
Sensory Cueing – What is it and how does it work?
Sensory cueing is a technique that has been widely adopted in the management of PD. It is defined as using an external stimulus to facilitate movement initiation and continuation. The stimulus can be delivered as a visual, auditory, or tactile signal. Recent research shows that sensory cueing can have an immediate and powerful effect on movement and gait in people with PD. (5) Sensory cueing can alleviate PD symptoms of slowness, stiffness, and freezing-of-gait. Cueing effectively bypasses the dopamine-deficient neuronal pathways and uses alternative ones that are unaffected by Parkinsonism.
The companies tackling the Challenges
At Spex Capital we’ve seen a large number of companies in this space and we’re in a privileged position to identify those companies which are effectively tackling some of the challenges faced by those living with PD. It’s inspiring to see the innovative technologies that are emerging to help improve the quality of life and reduce the debilitating symptoms. We would like to share with you the companies we are most excited about.
A number of companies are using sensory cueing to help improve the lives of those living with PD. Walk with Path have developed ‘Path Finder’ laser shoes which utilize visual cueing. Path Finder is a class I medical device that is a wearable laser attachment that can be fitted to shoes. The lasers point ahead of the feet and provide cueing in a step synchronised manner. Walk With Path report that their Path Finder laser shoes reduce freezing-of-gait by 50% and reduce falls by approximately 35%, leading to a 93% increase in confidence of people with Parkinson’s. (6)
Also using sensory cues to aid people with PD, is Charco Neurotech, who have developed Cue1. Cue1 is a non-invasive, wearable device which produces vibrotactile stimulation. The device delivers two types of scientifically validated stimulation: Focused stimulation and sensory cueing. The focused vibrotactile stimulation puts the body in a “ready-to-move” state which can in turn reduce the stiffness and slowness. Initial testing of the Cue1 has been reported to show that whilst using the device, all participants displayed faster movements in both hand and walking tasks, and they also felt that their movement was under more control. (7)
Strolll are taking things a step further with cueing therapy via their DTx software for augmented reality (AR) glasses. Reality DTx provides on-demand, personalised cueing to improve walking, postural instability and reduce falls for people with PD. Coloured lines on the floor can act as visual cues to help bypass the damaged neural pathways in the brain and reduce freezing-of-gait or other gait impairments. Strolll’s DTx software leverages these methods and provides a library of visual and auditory cues to alleviate motor symptoms and enable people with Parkinson’s to access personalised motor therapy and exercise. (8)
Gyrogear is developing a wearable glove “the Gyroglove” which will work by increasing hand stability using inbuilt gyroscopes to counteract the hand tremor seen in PD and essential tremor. The glove aims to restore confidence and improve activities of daily living by reducing the effect of the hand tremor. (9)
Manus Neurodynamica have produced the Neuromotor PenTM to aid the early diagnosis and monitoring of PD. Some symptoms of PD e.g., minor changes in the fine motor control of the fingers, and small handwriting (micrographia) as well as subtle tremors, are early indicators of the disease. The neuromotor pen combines sensor technologies built into a digital pen with an analytical engine and a decision support system. Using information gathered from a set of standardised handwriting and drawing tasks the neuromotor pen has been reported to provide an accurate and objective motor-cognitive assessment, offering a differential diagnostic test for PD. (10)
Watch this space….
What excites us about the space is that the power of sensory cueing is not solely limited to Parkinson’s Disease – there is research that suggests that cueing can be helpful in the rehabilitation of neurological disorders such as Stroke, Traumatic Brain Injury and Multiple Sclerosis. (11) Stroke alone will affect 1 in 4 people worldwide and if we can make even a small positive improvement in their rehabilitation and quality of life, a huge amount of positive impact will be made.
The companies bringing technology to the table that can help make an earlier diagnosis of Parkinson’s, reduce freezing-of-gait, and improve hand tremor, will undoubtedly improve the quality of life for people with Parkinson’s. Technological innovation will continue to transform healthcare and ultimately transform the lives of those with chronic conditions.
Bibliography
- Yang W, Hamilton JL, Kopil C, Beck JC, Tanner CM, Albin RL, et al. Current and projected future economic burden of Parkinson’s disease in the U.S. NPJ Parkinsons Dis. 2020;6:15.
- Beitz JM. Parkinson’s disease: a review. Front Biosci (Schol Ed). 2014;6(1):65-74.
- Heremans E, Nieuwboer A, Vercruysse S. Freezing of gait in Parkinson’s disease: where are we now? Curr Neurol Neurosci Rep. 2013;13(6):350.
- 2019 surveillance of falls in older people: assessing risk and prevention (NICE guideline CG161). London2019.
- Nieuwboer A, Kwakkel G, Rochester L, Jones D, van Wegen E, Willems AM, et al. Cueing training in the home improves gait-related mobility in Parkinson’s disease: the RESCUE trial. J Neurol Neurosurg Psychiatry. 2007;78(2):134-40.
- WalkWithPath. [Available from: https://www.walkwithpath.com/pages/path-finder-for-professionals.
- CharcoNeurotech. [Available from: https://charconeurotech.com/testing-results/.
- Strolll. [Available from: https://www.strolll.co/.
- GyroGear. [Available from: https://gyrogear.co/.
- ManusNeurdynamica. [Available from: https://www.manusneuro.com/.
- Palacios-Navarro G, Albiol-Perez S, Garcia-Magarino Garcia I. Effects of sensory cueing in virtual motor rehabilitation. A review. J Biomed Inform. 2016;60:49-57.
By Dr Alok Prasad and Dr Charlotte McIntyre
