Routine checkups may be enough to detect Parkinson’s disease years before symptoms appear

NAGOYA, Japan — A new discovery may change the game when it comes to Parkinson’s disease, the degenerative disorder which causes uncontrollable tremors. Researchers from Nagoya University have discovered that blood pressure levels, hematocrit levels (percentage of red blood cells in blood), and serum cholesterol levels in Parkinson’s patients tend to fluctuate from the norm long before actual symptoms appear.

This discovery may change how doctors diagnose and treat Parkinson’s. It may even open the door toward much earlier diagnoses. That last point is a major boon; earlier detection means earlier treatment which ultimately leads to better health outcomes for patients. In the long run however, there is currently no cure for the neurological condition.

Spotting Parkinson’s disease in advance

Parkinson’s disease is caused by a deficiency in the neurotransmitter dopamine. By the time a Parkinson’s patient starts exhibiting motor symptoms (stiffness, loss of balance, shaking), over half of their dopaminergic neurons are already gone. However, earlier research also suggests that milder symptoms like constipation, REM sleep behavior disorder, depression, and loss of smell can occur 10 to 20 years before any motor symptoms appear.

So, study authors decided to conduct this research based on the theory that Parkinson’s disease develops in the human body long before motor symptoms show themselves.

“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,” says Professor Masahisa Katsuno of the Graduate School of Medicine at Nagoya University in a university release.

Researchers decided to focus on the results of a series of general health checkups. Similar to the United States, Japanese citizens are encouraged to visit a general practitioner annually for a routine checkup.

Men and women have different warning signs

Study authors selected a total of 22 men and 23 women being treated for Parkinson’s. This group had multiple years of general checkup data available for researchers to examine, dating back long before their official Parkinson’s diagnosis. As a control group, study authors also analyzed health data on 120 men and women in generally good health.

To start, the study compared baseline health readings among Parkinson’s patients and health individuals against one another, after being separated according to gender. Among men, Parkinson’s patients showed lower levels of weight, BMI, serum creatine, hematocrit, and total and low-density cholesterol than their healthy counterparts. For women, Parkinson’s patients had higher levels of blood pressure and enzymes called aspartate aminotransferase in comparison to healthy females.

The research team then looked for specific fluctuations in any checkup readings before motor symptoms began to appear. They note that in the pre-motor stage, women exhibit higher blood pressure. Men show lower levels of hematocrit and total and low-density cholesterol.

“In this study, we found that blood pressure, hematocrit, and serum cholesterol levels are potential biomarkers of Parkinson’s disease before the onset of its motor symptoms,” Prof. Katsuno explains. “This finding indicates that general health checkups can help detect early signs of developing Parkinson’s disease.”

“We are also conducting clinical trials of medication in the individuals who are considered, based on their checkup data, to be at high risk for Parkinson’s, in an attempt to prevent the development of the disease in them,” Katsuno concludes.

The study is published in Scientific Reports.