Top 10 Parkinson’s Disease Stories of 2022
Risk factors, symptoms and treatments were hot topics for readers this year
Here are the 10 most-read articles of 2022, with a brief description of what made them interesting and relevant to the Parkinson’s community. We look forward to continuing our coverage of the latest Parkinson’s news in 2023.
Evidence presented at an October symposium further supported exposure to toxic environmental factors — like pesticides and air pollutants — as an important risk factor for neurodegenerative diseases, including Parkinson’s. In sharing their study results, the scientists emphasized the need for more efforts to limit such exposures, urging regulatory agencies like the U.S. Environmental Protection Agency to consider the impact of environmental pollutants on neurodegenerative disease. The researchers also called for increased funding for preventive measures and advocacy.
Some scientists think Parkinson’s can be divided into two types: brain-predominant, in which nerve damage is largely limited to the brain, and Parkinson’s with body-involvement, where nerve damage affects other parts of the body from early on. Here, researchers in South Korea showed that 103 patients with early dysfunction of the nerves controlling heartbeat — indicative of the body-involvement type — generally experienced faster disease progression than 29 patients without such dysfunction (brain-predominant disease). The body-involvement type was linked to more severe motor symptoms that worsened more quickly, as well as higher rates of non-motor symptoms such as sleeping problems, constipation, and blood pressure drops upon standing.
In addition to regulating the body’s calcium levels, vitamin D is important for modulating activity of the nervous system. Researchers in China analyzed blood levels of vitamin D in 112 Parkinson’s patients and 70 healthy people. The results showed that people with Parkinson’s generally had lower vitamin D levels than healthy people — and that patients with higher levels were less likely to have cognitive impairment or dementia. While the findings do not offer definitive conclusions on a cause-and-effect relationship between vitamin D and cognitive function in Parkinson’s, they support future studies on whether vitamin D supplements may be beneficial for these patients, the researchers noted.
Following more than 200 Parkinson’s patients in China for 10 years, researchers found that an older age at disease onset, faster disease progression, and more severe cognitive impairment were significantly associated with a higher risk of death. In contrast, physical exercise and deep brain stimulation, a surgical approach used to ease motor symptoms in some patients, were linked to a lower risk. These findings may be used to inform therapeutic strategies aiming at prolonging life expectancy, the researchers noted.
A large U.K. study that involved the most ethnically and socioeconomically diverse group of Parkinson’s patients yet reported found that several Parkinson’s symptoms can emerge as early as 10 years before a diagnosis. These symptoms included tremors and cognitive difficulties, as well as seizures and hearing loss — which had not been previously identified as risk factors of Parkinson’s and require further research. Notably, ethnicity and socioeconomic status themselves were not associated with Parkinson’s risk. The researchers noted that atypical disease symptoms and/or symptom underreporting among minorities may have led to Parkinson’s underdiagnosis in those groups.
At the Society for Neuroscience’s annual meeting, mouse studies conducted by different teams of researchers in the U.S. provided further evidence of gut-brain axis involvement in Parkinson’s development. Specifically, the data support that disease-associated hallmarks may start in the gut and then travel to the brain. In one study, a pesticide previously linked to a higher Parkinson’s risk was injected into the colon of healthy mice. Results showed the presence of toxic clumps of the alpha-synuclein protein — the underlying cause of Parkinson’s neurodegeneration — not only in the gut, but also in the nerve cells that innervate the digestive tract and a brain region implicated in Parkinson’s. Notably, the mice also developed motor problems. In another study, researchers found that oral exposure to an insecticide known to disrupt the signaling pathway lost in Parkinson’s led to alterations in both the gut and the brain, making mice susceptible to Parkinson’s-like symptoms.
A small study of 10 Parkinson’s patients found that swallowing difficulties, a non-motor manifestation of the disease, are significantly associated with dysfunction of the nerves that supply the heart muscle. This suggests that this common symptom may be linked to problems in the autonomic nervous system, which controls involuntary bodily processes such as heart rate, digestion, and breathing. The noninvasive technique used in the study to measure heart nerve dysfunction, called cardiac MIBG scintigraphy, could help identify patients at risk of swallowing problems, the researchers noted. Still, further studies are needed to confirm and better understand these findings.
Cranberries have high amounts of antioxidant chemicals called polyphenols. Given that antioxidants are able to combat oxidative stress — a type of cell damage implicated in Parkinson’s — polyphenol-abundant berries have gain increased interest as potential therapeutic strategies. In a study we reported on in May, a team of researchers in Poland found that concentrated cranberry juice lowered alpha-synuclein buildup, prevented brain cell death, and improved motor function in a rat model of Parkinson’s disease. However, the team also found evidence suggesting that long-term consumption of high doses of cranberry juice may have negative consequences on brain cells. Thus, while cranberry may offer a good supplement to Parkinson’s treatment regimens, further research is needed to optimize the appropriate dose.
An international team of researchers found that a combination of online cognitive games and noninvasive brain stimulation — a program called COGNISANT — can boost short-term memory in older adults. While all 28 healthy participants saw memory improvements regardless of whether they received brain stimulation, older participants with lower initial memory capacity benefitted the most from the combined approach. Such an approach may help to improve memory for people with Parkinson’s, who often experience difficulties in remembering that interfere with daily life. The researchers have planned additional studies to explore the benefits of brain stimulation on cognitive function.
Our number one story of 2022 concerned a study in Germany that showed that a modified version of the Interlocking Finger Test (ILFT), a bedside screening tool, could help detect dementia in Parkinson’s patients. Testing of this tool was based on the fact that visuospatial problems can predict the eventual development of dementia. Essentially, the simple, noninvasive ILFT involves an examiner putting his or her hands into a specific shape and asking the patient to mimic it. How well the patient can reproduce the specific shape forms the basis of the evaluation, with a highest possible test score of 15. Among 47 Parkinson’s patients, a lower ILFT performance was significantly associated with older age and worse performance on cognitive function and memory tests. Researchers suggested that ILFT scores of 12.5 or lower could be used to predict visuospatial problems, and scores of 10.5 or lower could predict Parkinson’s dementia.
At Parkinson’s News Today, we hope these stories and our reporting throughout next year helped to inform and improve the lives of everyone affected by Parkinson’s.
We wish all our readers a happy 2023.