It currently affects around 11.8 million people worldwide, with approximately 500,000 cases in Brazil. Experts warn that the increase in the prevalence of the condition already exceeds that of diseases such as Alzheimer’s, epilepsy and headaches.
No program this Saturday (10), the conversation with neurologists Roberta Saba e Rubens Cury about what happens in the brain of Parkinson’s patients and what are the factors associated with the development of the disease.
What happens in the brain?
According to Roberta, general secretary of Brazilian Academy of Neurologythe disease causes changes in a brain region called black substance. “In this region, there are neurons that produce a type of brain hormone, a neurotransmitter called dopamine,” he explained.
“Dopamine is essential for regulating the body’s normal movements. With the progressive degeneration of these neurons, the characteristic symptoms of the disease appear: slowness of movement, muscle rigidity and, often, resting tremor”, detailed the neurologist.
Causes and risk factors
The cause of Parkinson’s disease has not yet been completely elucidated by science. Roberta Saba explained that, therefore, the condition is classified as having an idiopathic cause. “It’s a combination of genetic factors and environmental factors,” he said.
To illustrate, she cited the case of an identical twin patient whose brother, an agricultural engineer, developed the disease — probably due to exposure to pesticides — while he, a lawyer, did not develop it. “Environmental factors are increasingly related to the onset of Parkinson’s disease,” he highlighted. “We, however, still cannot define what causes one individual to develop the disease and another not.”
Rubens Cury, coordinator of the Deep Brain Stimulation Outpatient Clinic at the Hospital das Clínicas of the Faculty of Medicine of USP, reinforced that factors such as increased industrialization, pollution and the use of pesticides are among the environmental elements investigated.
“We have studies in USA by you South Korea showing that in more polluted regions the incidence is higher”, he stated. According to him, the combination of genetic predisposition with environmental exposure appears to be the main mechanism behind the development of the disease.
Age of manifestation and heredity
Rubens Cury clarified that there is no specific age for the onset of Parkinson’s, although the prevalence is significantly higher above 55 years of age. “The older you are, the greater the chance of a person having Parkinson’s,” he explained. When the disease manifests before the age of 50, it is called early Parkinson’s diseaseand is generally associated with a high genetic predisposition.
Regarding heredity, Cury explained that only in around 10% of cases is it possible to identify an altered gene responsible for the condition. “In 90% of cases, the genetic test is negative”, he pointed out. This reinforces the predominant role of environmental factors and the interaction between genetics and environment in the development of the disease.
