April 11, 2025 – Two incurable diseases loom over our aging populace: Parkinson's and Alzheimer's. Right now, Alzheimer's is more common and seems a more widespread concern than the relatively narrow shadow cast by Parkinson's.
That may change, as revealed by a surprising new study.
North American cases of Parkinson's disease are projected to increase 30% by 2050, and will double globally, according to the study, published last month in the journal The BMJ.
That's about 25 million people worldwide by 2050 – the kind of prediction that gets attention in the realms of public health, insurance, hospitals, and politics.
But what should it mean to you?
A lot, said Parkinson's expert Alfonso Fasano, MD. Alzheimer's is the most common nerve-degrading disease, he said, citing recent dementia figures. If dementia rates continue to decline as they have been, Parkinson's will take over first place in the coming decades, he said.
"People need to know about it because there is something that can be done to prevent, if possible, the occurrence of the disease, but also to live better with the disease if you get it," he said.
The field of Parkinson's research is afire with recent breakthroughs in diagnostics and treatments. Symptoms mostly affect movement – slowing down, stiffness, and tremor while at rest. Others range from mental health effects to pain and fatigue.
If you think Parkinson's means being wheelchair-bound with a short life expectancy, it's time for an update.
"People shouldn't be scared. This is not terrible news," said Xuemei Huang, MD, PhD, department chair and a professor of neurology for the University of Virginia Health System and School of Medicine.
She published a study in January showing that most people with Parkinson's who receive specialized care continue to independently carry out their daily activities for 10 to 15 years after diagnosis.
"Once upon a time, in the 1950s, before we even knew about the role of dopamine in the brain and before we knew much about Parkinson's disease, the average life expectancy of Parkinson's patients was seven to eight years," Huang said. "Many would be wheelchair-bound by the fifth year."
Like soon-to-be second place dementia, though, there is no cure for Parkinson's disease. Scientists are working to decipher the combination of factors that trigger its start. A small portion of cases are clearly driven by genetics, but lifestyle and environmental factors figure prominently.
Early Signs of Parkinson's – and New Ways to Manage It
Researchers can spot clues of impending Parkinson's disease. Early detection can be crucial for a longer, richer life.
"Some people might have signs that tell us that their brain is cooking Parkinson's disease, even if they don't have Parkinson's disease," said Fasano, a professor of neurology at the University of Toronto and a staff neurologist at Humanitas University in Milan, Italy.
Some of these long-familiar signs are better understood now, like a reduced sense of smell and a condition called REM sleep behavior disorder. With this condition, people act out their dreams without waking, by talking, moving, or making gestures. (Usually, a brain mechanism keeps us immobile during sleep.)
"Once, I saw a video of a person who was pretending to smoke a cigarette and talking to someone," said Fasano. "Some people are dreaming of being attacked or chased by bad people, and they start fighting. And there are also some situations where the bed partner has been hit by the person who was dreaming."
This can be a symptom as many as 15 years before a Parkinson's diagnosis.
There's a new, same-day blood test that Fasano calls "a miracle." The test, called RT-QuIC, looks for a protein called synuclein that is evident in the brains of people with Parkinson's 95% of the time. It's a protein that can disrupt normal cell and organ function.
"Some people have this positivity for this test years and years before they have the onset of the disease," Fasano said. "The catch, though, is that some people don't have the accumulation of synuclein" and still develop Parkinson's.
On a parallel track are developments in late-stage Parkinson's care. New medications are ready for review by the FDA, including tavapadon, which in phase III trials significantly improved movement symptoms and daily living.
And just last month, hospitals began offering an updated technology for a longtime treatment called deep brain stimulation.
For those in the early stages, Huang noted, a longer life could still eventually result in limited mobility and a loss of intelligence due to dementia.
A recent analysis by her team found that about 20% of the 1 million people in the U.S. who have Parkinson's disease also require a caregiver and the use of a wheelchair, along with having a dementia diagnosis.
Huang is optimistic that more breakthroughs are on the horizon.
Advances in Deep Brain Stimulation
This year, a longtime technology for late-stage Parkinson's got a major upgrade. Surgically placed electrodes in the brain deliver electrical pulses to lessen symptoms. Called deep brain stimulation, or DBS, it's been likened to a pacemaker for the brain and has been around since 1997. But it required in-office programming that could not be fine-tuned without return visits.
A newly FDA-approved upgrade called adaptive DBS was rolled out to dozens of patients in Colorado starting at the end of March. Using aDBS, the power and duration of electrical pulses adjust to signals sensed in the brain in real time. The improved treatment reduces side effects, particularly uncontrolled muscle movements called dyskinesia, which can cause, for example, writhing so severe that one may fall out of a chair.
One patient, Kate Goes In Center, 75, of Denver, said it has helped. Parkinson's disease, she said, "affects my chin and my throat, everything. It's hard for me to swallow, and it's hard for me to talk." She volunteered to be the first aDBS patient at UCHealth University of Colorado Hospital. Video of the new technology showed instant effects.
"How do you feel?" one of her doctors, Drew Kern, MD, MS, asked her after she took a short walk around the treatment room and sat back down. Kern is an associate professor at the CU Anschutz School of Medicine's departments of Neurosurgery and Neurology.
The results clearly came right away. Her tremor was pretty much gone.
She raised her eyebrows as she said to him, "A lot better."
"I had kind of given up for a while," Goes In Center, a former runner, said later. "I felt like I wanted to go because my life was so difficult every day, and this gives me a lot of hope. And exercise is key to keeping you active. I couldn't even get myself to exercise because I was afraid of falling – I did fall once and broke my wrist last summer – but this makes a difference. I feel like I could [exercise] again."
Exercise is among the areas of future study with aDBS, because already, physical activity has been shown to potentially slow the progression of Parkinson's disease. The new aDBS technology includes something called an electrode identifier that Kern and his colleague John Thompson, PhD, also a CU associate professor, helped develop. It helps collect real-time data from each patient, which can help fine-tune treatment. The data can also help health professionals make other treatment decisions and can be useful in broader disease research.
Exercise not only affects disease progression, but also is a factor in prevention.
"For North America, it is now known that a certain lifestyle is protective, particularly exercising, low body mass index, a lot of aerobic exercise, and lack of diabetes," said Fasano. "These seem to be more protective of neurodegeneration of the type seen in Parkinson's disease."
New Clues About the Causes of Parkinson's
What causes Parkinson's is believed to be a complex interplay of genetics, risk factors like diabetes and obesity, and environmental influences, the last of which is very difficult to study. But evidence continues to point to pollution in large cities, especially two specific exposures: living next to or downwind of croplands that use certain herbicides, and being exposed to certain toxins such as those used by dry cleaners.
One link between agricultural chemicals and Parkinson's disease was discovered by accident.
In the late 1980s, attempts to concoct a heroin-like drug resulted in a chemical called MPTP, Fasano said. "And this product is extremely toxic to the cells producing dopamine. So these people injected themselves, and the next day, literally, they had severe Parkinson's that was irreversible."
MPTP is now used in animal research into Parkinson's. "So in the lab, when they want to create something that looks like Parkinson's, they use this product," Fasano said.
More important, it turns out that MPTP has a similar chemical makeup to an herbicide called Paraquat, which is banned in Europe but still used in the U.S. So researchers examined rates of the disease where the herbicide is used.
"If you look at the prevalence of Parkinson's in rural areas where there is more agriculture, you will see that there is more Parkinson's," Fasano said.
A new paper, published in January, linked higher rates of Parkinson's to areas in the Great Plains near croplands. Its lead author is Brittany Krzyzanowski, PhD, an expert in geographical analysis and spatial epidemiology who studies huge data sets of environmental, health, and agricultural data to better understand Parkinson's disease risk factors.
"We also decided to see if we could identify which crop types were riskier in terms of Parkinson's, because certain crop types are applied with certain pesticides," said Krzyzanowski, an assistant professor at Barrow Neurological Institute in Phoenix. "We found sunflowers and alfalfa fields were driving the association, likely due to the particular pesticides used on those crops."
It's also much windier in that part of the country, she said, and the pesticides might drift and affect a bigger area.
She also published a study late last year that linked Parkinson's risk to air pollution, in which the research team calculated average annual exposure to nitrogen dioxide and particulate matter – the tiny particles suspended in the air, such as from car exhaust, power plants, and wildfires.
"Right now, my models have led me to things that have already been known," Krzyzanowski said. "I've become more and more motivated to find the unknown."
Among her current projects are analyzing health data for people living near golf courses and near dry cleaners. Maybe, she said, she will identify a spot that appears to be toxic so something can be done about it.
Fasano acknowledged it's hard to calculate environmental risk or add up your own lifetime list of environmental risks.
He and others are working toward something called an "exposome."
"It means all the things that someone has been exposed to, or a lot of protective factors, that one's been exposed to throughout their life, and it's extremely difficult to study," he said. "It's never a linear relationship … but as I said before, knowing something is about to happen, bracing for something that's about to happen, clearly gives you an advantage."
There are easy ways the average person can adjust their everyday life to reduce risk, Krzyzanowski said.
She urged people to learn about their tap water and air quality, pointing to a website by the Environmental Working Group and an app from PlumeLabs.
"There are many small steps a person can take to reduce their exposure to toxins. The primary things would be to buy organic produce, use a carbon filter for your drinking water, and consider using an indoor air purifier," she said.
