Changes in blood pressure, hematocrit and cholesterol levels — vital signs often collected at routine health screenings — may help physicians detect early signs of Parkinson’s disease, finds research led by scientists in Japan.

Nagoya University researchers analyzed multiple years of data from the checkups of 22 male and 23 female patients with Parkinson’s disease whose checkup results before the onset of motor symptoms were available. They compared the results with data from the checkups of 60 male and 60 female healthy individuals who underwent checkups for at least four years.

Their findings showed that the weight, body mass index, hematocrit, total and low-density cholesterol levels and serum creatinine levels were lower among the males in the process of developing Parkinson’s than those in healthy male individuals. Blood pressure levels and an enzyme called aspartate aminotransferase were higher, whereas other items’ values were lower among the female Parkinson’s patients compared with the females without Parkinson’s.

These results suggest that Parkinson’s disease develops decades before the onset of motor symptoms, said study co-author Masahisa Katsuno, M.D., a professor in the graduate school of medicine at Nagoya University. 

“If we can detect biological changes in the patients’ bodies well before the onset of the motor symptoms, we can start medical treatments in an early stage,” Masahisa said.

Full results are published online in Scientific Reports.

In related news, University College London researchers have found that simple vision tests can predict which people with Parkinson’s disease will develop cognitive impairment and possible dementia 18 months later.

The team examined 77 patients with Parkinson’s disease and found that those with visual impairments were more likely to develop dementia. The study, published in Movement Disorders, adds to evidence that vision changes precede the cognitive decline that occurs in many, but not all, people with Parkinson’s, the researchers wrote.

A second study by the same research team, published Tuesday in Communications Biology, found that structural and functional connections of brain regions become decoupled throughout the entire brain in people with Parkinson’s disease, particularly among people with vision problems.

Together, the two studies show how losses and changes to the brain’s wiring underlie the cognitive impairment experienced by many people with Parkinson’s disease.

“Vision tests might provide us with a window of opportunity to predict Parkinson’s dementia before it begins, which may help us find ways to stop the cognitive decline before it’s too late,” said lead author Angeliki Zarkali, an Alzheimer’s research fellow at UCL.