Scientists Warn of Rising Parkinson’s Rates—Here Are 8 Early Signs to Know

A new study found that Parkinson’s disease will rise globally by 112% between 2021 and 2050, jumping from nearly 12 million cases to 25.2 million. 

Researchers used disease trends data from 195 countries and factored in variables influencing case rates for their analysis, published in The BMJ. In a linked editorial, two other researchers said the projection is likely an underestimate.

In the United States, diagnoses are estimated to rise by up to 60%. An estimated one million people in the U.S. already have the neurological condition, which largely affects movement. A recent study estimated that cases have been steadily increasing, with about 90,000 people diagnosed annually, up from 40,000 to 60,000 roughly a decade ago.

Parkinson’s primarily affects older adults, and the researchers found that rates are projected to increase most in people older than 80. The authors attribute the overall rise in cases primarily to a growing aging population.

While there’s no cure for Parkinson’s, a timely diagnosis may help slow the progression of severe disease. With cases rising, here’s what to know about Parkinson’s, including how to spot it in the early stages.

Parkinson’s is a progressive disease. It can occur when dopamine-producing nerve cells near the base of the spine become damaged and die. Those cells produce dopamine, which signals the brain to allow you to move smoothly and intentionally.

Researchers don’t know the exact cause of these changes. Genes are central in about 10% to 15% of cases. Some environmental factors, like head injuries and pesticide exposure, can also elevate your risk, as can being male and living in certain parts of the country, like the “Rust Belt” in the Northwest and Midwest. It’s believed that Parkinson’s results from a combination of genes and environmental factors. 

“The pathology of Parkinson’s disease may begin in the nose (brain-first) or the gut (body-first), providing a powerful link to environmental toxicants,” Earl R. Dorsey, MD, a neurology professor at the University of Rochester, told Health in an email.

Symptoms usually start slowly and can remain subtle for a lengthy period. A combination of medications, therapies, and certain lifestyle adjustments can help manage symptoms.

While the symptoms of Parkinson’s can be wide-ranging, here are eight that can crop up in the early stages of the disease:

Loss of smell. Losing the ability to smell is a common early sign of Parkinson’s. Most people who develop the disease will experience this symptom at some point.

Constipation. This is perhaps the most widely recognized gastrointestinal symptom of Parkinson’s, per the Parkinson’s Foundation, and it often begins before motor symptoms. 

Tremor. About 70% to 80% of people experience a tremor, James Beck, PhD, chief scientific officer at the Parkinson’s Foundation, told Health. The typical tremor occurs at rest and eases during sleep or when you’re partly active. Symptoms tend to start on one side, likely in a hand, but can also occur in the lower lip, leg, or jaw. About 50% of people with Parkinson’s have a tremor that occurs when their arms stretch outward. Some people report an internal shaking sensation in their limbs, abdomen, or chest that’s not visible.

Sleep interruptions. Many things can disrupt your sleep, so issues getting shut-eye aren’t necessarily indicative of Parkinson’s disease. However, sudden movements during sleep can be a specific sign of Parkinson’s. 

Small handwriting. People with Parkinson’s sometimes have changes in their handwriting, like it becoming smaller and more cramped.

Movement changes. Parkinson’s can bring on a cluster of movement changes. You may move more slowly, arms may not swing like they used to when walking, and blinking and smiling might be more difficult. Pain can occur. For example, some people with frozen shoulder might eventually discover that the issue is not a problem with the joint but instead neurological, Beck said.

Speech changes. Voice changes—becoming softer, hoarser, or slurred—can be a common Parkinson’s feature.

Anxiety. Non-motor symptoms like anxiety and depression can be an indicator that Parkinson’s is developing. These symptoms aren’t always a reaction to Parkinson’s but could be the result of changes in brain chemistry. 

As the disease progresses, many people with Parkinson’s experience dizziness or vertigo. Changes in posture, such as bending the neck, slumping the shoulders, and bending the wrists, knees, and other joints, are also common. Eventually, some people may be difficult to carry out daily tasks. 

Some signs of Parkinson’s overlap with other health issues, making diagnosis more complicated. Experts recommend talking to your doctor about any symptoms that are concerning.

Because there’s no singular test for the disease, doctors rely instead on a patient’s medical history, description of symptoms, and family history. If Parkinson’s runs in the family, a genetic test may be ordered.

Your doctor may do a neurological exam to assess the presence and severity of motor symptoms. There are several, including tremor and gait assessments and a repetitive movement test, which evaluates your ability to perform tasks like tapping your toes or opening and closing a hand.