Parkinson's disease is a progressive neurological disorder primarily affecting the central nervous system. It impacts both motor and non-motor functions, with symptoms typically appearing gradually. Common signs include tremors, slowed movements, stiffness, and balance issues, collectively termed parkinsonism. As the disease advances, non-motor symptoms like dementia, falls, sleep disturbances, psychosis, mood fluctuations, and behavioral changes may emerge.
Casimir Funk first synthesized levodopa in 1911, though its significance in treating Parkinson's disease was not yet realized.
Frederic Lewy's description of microscopic particles, later known as Lewy bodies, in affected brains in 1912, marked a pivotal discovery in understanding the pathology of Parkinson's disease.
Konstantin Tretiakoff's 1919 report identified the substantia nigra as a critical area affected by Parkinson's disease, a finding initially contested but later validated.
Rolf Hassler's studies published in 1938 provided crucial confirmation of the substantia nigra's significant role in Parkinson's disease.
William Black founded the Parkinson's Disease Foundation in 1957, and it has since provided over $115 million towards research and almost $50 million for educational and advocacy initiatives.
The American Parkinson Disease Association was established in 1961.
In 1967, levodopa entered clinical practice and marked a turning point in managing Parkinson's disease, significantly diminishing the reliance on then-common treatments like anticholinergics and surgery.
The Hoehn and Yahr scale, first published in 1967, provided a groundbreaking standardized method to assess the progression of Parkinson's disease, categorizing it into five distinct stages.
In 1981, a Dutch horticulturalist registered the 'James Parkinson' tulip cultivar.
Since its inception in 1982, the National Parkinson Foundation has contributed more than $180 million to patient care, research, and support services.
Parkinson's disease caused a significantly lower number of deaths globally in 1990, highlighting the disease's growing impact over time.
The European Parkinson's Disease Association was founded in 1992.
A major breakthrough in 1997 was the identification of alpha-synuclein as the primary component of Lewy bodies by Spillantini, Trojanowski, Goedert, and others, significantly advancing the understanding of the disease's underlying mechanisms.
Actor Michael J. Fox, diagnosed with Parkinson's disease at 29, established The Michael J. Fox Foundation in 2000. The foundation has since raised over $2 billion for Parkinson's research, significantly contributing to the fight against the disease.
Olympic medalist and cyclist Davis Phinney, diagnosed with Parkinson's at 40, established the Davis Phinney Foundation in 2004 to support research efforts in the field.
To raise awareness, April 11th, James Parkinson's birthday, was declared World Parkinson's Day, and in 2005, a red tulip, specifically the 'James Parkinson' cultivar, was designated as the symbol of the disease by international organizations.
A 2007 study revealed the substantial economic burden of Parkinson's disease, with inpatient care and nursing homes being the largest contributors to direct costs. The disease also carries significant indirect costs due to decreased productivity and the strain on caregivers, along with a reduced quality of life for both patients and their families.
A 2010 meta-analysis suggested that using nonsteroidal anti-inflammatory drugs (NSAIDs), except for aspirin, might lower the risk of developing Parkinson's disease.
In 2011, phase two clinical trials exploring gene therapy for Parkinson's disease, specifically the delivery of GAD, demonstrated potential. While the approach effectively improved motor function, it was not as effective as deep brain stimulation (DBS).
The passing of actor and comedian Robin Williams in 2014 brought to light the complexities of diagnosing Parkinson's disease. Though initially diagnosed with Parkinson's, his autopsy revealed dementia with Lewy bodies, underscoring the difficulties in accurate diagnosis.
In 2016, Parkinson's disease led to approximately 211,000 deaths worldwide, marking a significant increase of 161% since 1990.
The year 2016 marked a significant milestone in treating Parkinson's disease psychosis with the approval of pimavanserin, offering a new therapeutic option for this challenging symptom.
A 2017 study estimated the economic impact of Parkinson's disease in the United States at $51.9 billion, which included $25.4 billion in direct medical expenses and $26.5 billion in indirect and non-medical costs.
In 2018, an antibody called PRX002/RG7935 demonstrated initial safety and efficacy in stage I trials, prompting further investigation in stage II trials.
However, by 2019, subsequent meta-analyses failed to confirm the previously suggested link between NSAID use and a reduced risk of Parkinson's disease.
In 2019, istradefylline, an antagonist of adenosine receptors, received approval for medical use in the United States as a supplemental treatment option for patients with Parkinson's disease who are already on a levodopa/carbidopa regimen.
A vaccine designed to help the immune system target and eliminate alpha-synuclein, known as PD01A, entered clinical trials. Initial findings from a phase one study in 2020 indicated that the vaccine was safe and well-tolerated.
In 2020, a Cochrane review found no conclusive evidence to support cognitive training as a beneficial treatment for Parkinson's disease, dementia, or mild cognitive impairment.
To represent the varying levels of severity in Parkinson's disease, a new image was created in 2020, updating the previous illustration from 1886 by William Richard Gowers.
By 2021, Parkinson's disease earned the grim distinction of being the fastest-growing neurodegenerative disease globally, considering both mortality and prevalence rates, emphasizing the urgent need for research and effective treatments.
As of 2022, the lack of disease-modifying drugs for Parkinson's disease remains a significant challenge, driving intensive research efforts. Current research focuses on various avenues, including developing new animal models, exploring gene therapy, stem cell transplants, and investigating neuroprotective agents. Additionally, to enable earlier intervention, research criteria are being established for identifying prodromal biomarkers.
As of 2023, research indicated no direct correlation between the progression of Parkinson's disease and the overall disability experienced. However, the type of disability varied with disease stage, shifting from primarily motor-related to non-motor symptoms.
Reviews conducted in 2023 reaffirmed the importance of exercise programs for individuals with Parkinson's disease, demonstrating their efficacy in managing symptoms and improving quality of life.
As of 2024, Parkinson's disease classification is based on symptoms, but active research aims to establish a more definitive biological basis for diagnosis.
As of 2024, the exact cause of Parkinson's disease remains unknown. However, it's believed to be a complex interplay of genetic and environmental factors. Age is a primary risk factor.
By 2024, approximately 90 genetic risk variants had been identified in connection with Parkinson's disease, significantly advancing the understanding of its genetic underpinnings.
In 2024, the cause of rigidity, a common symptom of Parkinson's disease affecting muscle stiffness, remained unclear. Research continues to investigate if it's a distinct biomechanical process or a manifestation of another Parkinson's symptom.
Projections for 2030 indicate a concerning trend, with China anticipated to have nearly half of the world's Parkinson's disease population.
The total economic burden of Parkinson's disease is projected to exceed $79 billion by 2037, emphasizing the urgent need for interventions to lower incidence rates, slow disease advancement, and alleviate symptoms to mitigate the future economic strain.
Looking further ahead to 2040, the number of Parkinson's disease patients is expected to reach approximately 14 million, underlining a global health challenge.