Ad
The retired N.F.L. quarterback Brett Favre told a congressional committee on Tuesday that he had been diagnosed with Parkinson’s disease, a progressive, incurable condition that causes tremors and stiffness, often resulting in impaired movement and speech.
The Republican-led committee was hearing testimony related to a sprawling welfare scandal in Mississippi in which millions of federal dollars earmarked for needy families went instead to the wealthy and powerful, including Mr. Favre.
Here’s what to know about the diagnosis, symptoms and treatment of the condition, which affects at least 1 percent of people over 60.
What is Parkinson’s disease?
Parkinson’s disease affects the central nervous system. It causes nerve cells in the brain to weaken and eventually die, leading to symptoms that include tremors and impaired balance, according to the National Institute of Neurological Disorders and Stroke. Slowness of movement is the classic feature, said Dr. Vikas Kotagal, an associate professor of neurology at the University of Michigan.
As symptoms progress, people with Parkinson’s disease may struggle to walk, speak and carry out other basic tasks. An estimated three-quarters of people living with Parkinson’s for more than 10 years will develop dementia.
Who is at risk of Parkinson’s disease?
Genetic mutations are linked to about 10 to 15 percent of Parkinson’s diagnoses, said Dr. Michael S. Okun, a neurologist at the University of Florida.
Environmental and other factors are at play much more often. Farmers who worked with pesticides and factory workers exposed to toxic chemicals are at greater risk of developing Parkinson’s, he said.
Some patients will never progress beyond early stages of the disease, whereas others will advance quickly to being unable to walk or even stand without using a walker, Dr. Kotagal said.
Can head injuries cause Parkinson’s?
A traumatic blow to the head, with or without loss of consciousness, may also increase a person’s risk of developing Parkinson’s, research has found. This link gained popular attention after the boxer Muhammad Ali was diagnosed at age 42 in 1984.
There’s growing evidence that head trauma and concussion are associated with a higher risk of developing the disease, said Dr. Okun, who was on Mr. Ali’s team of specialists.
A 2018 study of U.S. military veterans found that those who had suffered mild traumatic brain injuries, including concussion, had a 56 percent increased risk of Parkinson’s, even after controlling for demographics and other medical conditions. Those with moderate-to-severe traumatic brain injuries had an 83 percent increased risk.
“We don’t know exactly what the mechanism is,” said Dr. Kristine Yaffe, the senior author of that study and a professor of psychiatry, neurology and epidemiology at the University of California, San Francisco.
One leading theory is that something about these head injuries causes abnormal protein buildup in the brain, Dr. Yaffe said. Another is that head trauma causes inflammation and changes to blood flow and blood vessels that in turn leads to the death of brain cells.
How is Parkinson’s diagnosed?
A neurologist makes a diagnosis based on a patient’s medical history, a review of symptoms, and a physical and neurological exam. That exam tests memory, mental acuity, coordination and reflexes.
In people with a family history of Parkinson’s, genetic tests can be ordered to look for gene mutations that are associated with the disease.
The first signs that a patient may have Parkinson’s can be quite varied. Loss of smell, constipation, the acting out of vivid dreams, anxiety and depression can all manifest before the signature symptoms of Parkinson’s, like a resting tremor or stiffness.
“We’ve learned there can be clues that appear first,” Dr. Okun said.
Because of the huge range of potential symptoms and the slow progression of the disease, Dr. Okun said that Parkinson’s was considered one of “the most complex diseases in medicine.”
How is the Parkinson’s treated?
In the 1960s, Oleh Hornykiewicz, a pharmacologist, was among a handful of scientists to identify a deficiency of the neurotransmitter dopamine as a cause of Parkinson’s disease. Dr. Hornykiewicz and his assistant then developed a treatment with L-dopa, a chemical precursor to dopamine.
L-dopa, or Levodopa, is still a mainstay treatment for Parkinson’s disease, especially in the early stages, said Dr. Kotagal. It can help patients with their speed of walking and fine motor skills — like buttoning buttons, zipping zippers and holding utensils.
In later stages of the disease, Dr. Kotagal said, treatment consists mainly of administering as much Levodopa as is helpful without getting disabling side effects, and managing other symptoms of Parkinson’s like depression and lightheadedness.
A type of brain surgery called deep brain stimulation can benefit a small minority of patients, Dr. Kotagal said. And with no cure or treatment yet to halt Parkinson’s, researchers are studying personalized therapies to tailor electrical stimulation to a patient’s individual symptoms, and looking at whether a medication similar to popular obesity drugs can slow down the progression of the disease.
Ad
