Approximately 90,000 people in the U.S. each year are diagnosed with Parkinson’s disease (PD)1, a disabling, degenerative movement disorder that has no known cure. The primary symptoms of PD are tremor (rhythmic shaking of the body) and slow movements, although PD can also impact speech, cognition, sleep, mood, and many other domains. Each individual can experience a different subset of these symptoms, and their severity can differ from one person to the next.
People with PD benefit from the existence of two commonplace treatment options: medication and brain stimulation implants. These now tried-and-true treatments target the regions of the brain known to be primarily affected by this disorder, and they are viewed as the primary lines of defense against worsening symptoms. However, these treatments do not fully eliminate all symptoms of the disorder, and they can become less effective over time. Rehabilitation therapy has been shown to provide a significant benefit to people with PD over and above these other treatments, and rehabilitation can even help to slow disease progression.2, 3, 4, 5, 6 Thus, rehabilitation is a critical component of care that should be started immediately after diagnosis and revisited regularly. Yet, it is estimated that fewer than half of all people with PD are ever referred to rehabilitation therapy,7, 8, 9 meaning that a significant proportion of people miss out on these benefits.
PD rehabilitation comes in a variety of flavors. Physical therapy supports functional independence by working to improve movements like walking and the ability to maintain standing balance. Physical therapy can also help people with PD stay active and mobile. Occupational therapy supports the performance of ‘activities of daily living’ like dressing or bathing, as well as participation in meaningful activities like work or hobbies. Speech language pathologists help people with PD maintain their ability to communicate. They can also help with safely swallowing food and maintaining cognitive abilities like memory and thinking. These complementary disciplines work together to support all aspects of a person’s life.
In the early stages of the disease, rehabilitation often focuses on establishing good habits to help prolong independence as symptoms progress. At later stages, rehabilitation helps people to keep on top of any changes in their symptoms while maintaining the ability to engage in meaningful life activities. Thus, rehabilitation therapists help people with PD to overcome the functional challenges they may face as their symptoms progress, and they seek to equip people with the necessary tools to safeguard against future difficulties. In this way, rehabilitation therapy complements regular participation in exercise programs and social activities like community support groups to help people maintain their quality of life.
Rehabilitation therapies for PD have been heavily influenced by the Lee Silverman Voice Therapy (LSVT) technique, which was developed in the early 1980s.10, 11 Originally developed to improve hypophonia, a reduction in the volume of speech, LSVT encourages people with PD to “think loud” and focus on making loud sounds. The principles underlying LSVT have also been translated to movement rehabilitation (a technique called LSVT BIG), which trains people with PD to make larger movements.12 LSVT BIG is often used to help restore more normal movement patterns, such as overcoming the slow, shuffling walking pattern characteristic of PD.13 However, recent studies have shown that these current techniques have their limitations. People with PD remain dependent on caregivers for reminders to apply the principles taught during therapy in daily life.14, 15, 16 Some studies have also shown that people with PD benefit substantially from longer or more intense bouts of rehabilitation therapy, indicating some room for improvement in current approaches.17, 18, 19
Thanks to scientific advances, our knowledge of how PD impacts the brain and body has expanded over the past 40 years. Current therapy approaches can therefore stand to benefit from some updating to increase their efficiency, enhance efficacy, and to take advantage of our improved understanding of PD. Yet, discovering the next big improvement in PD rehabilitation will require dedicated rehabilitation research. However, funding for this kind of research is hard to come by. In PD research, federal agencies, like the National Institutes of Health, and private funding foundations have historically focused on discoveries in pharmacological, neurosurgical, and genetic treatments. While a small fraction of federal dollars, foundation grants, and philanthropic gifts are directed toward rehabilitation-focused research, it is not at the top of most funding priority lists. For example, according to the NIH RePORTER website, over the last 5 years only about 10% of federal grants related to Parkinson’s disease were awarded to projects related to rehabilitation. This will likely worsen with the proposed cuts to federal science funding.
For the millions of people currently living with PD, rehabilitation therapy offers tools to help them improve their lives now, while they wait for the next breakthrough in medical treatment or disease prevention. Thus, it is equally important that research dollars be allocated to support the investigation of improved rehabilitation strategies for PD. In particular, we need to develop more effective, tailored rehabilitation approaches that can target the specific set of symptoms each individual experiences. These strategies require, in turn, basic science research to improve our understanding of how the neurological damage caused by PD produces the specific symptoms that people experience. To that end, it is critical to support funding for basic human research and rehabilitation research in order to help people currently living with PD maintain their independence and quality of life.
References
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