The risk of Parkinson’s disease is significantly higher among people with depression than the general population. The severely depressed are at the greatest risk, according to an article published online last week by Neurology, the journal of the American Academy of Neurology. In fact depressed people are three times more likely to develop Parkinson’s than normal individuals.
These conclusions are based on a review of data on more than 560,000 people in Sweden. The more severe the depression, the higher the risk of Parkinson’s. The findings indicate that depression may in fact be a warning sign or even early phase of Parkinson’s, a nervous system disorder marked by tremors, slurred speech, stiffness, an unusual gait and other mobility issues.
“The research endorses the known links between psychiatric and neurological disorders,” said Carol Schramke, an Allegheny General Hospital clinical psychologist who was not involved in the study. In other words, what appears merely to be depression might in fact be a pointer to other far more serious brain-related problems like Parkinson’s, Alzheimer’s, epilepsy or even multiple sclerosis.
The possibility of a second disorder is particularly strong when a person’s first bout of depression comes returns in life, she said.
While there are no treatments to prevent or cure Parkinson’s, if preventive measures are developed in the future then Schramke said, it might become possible to identify the patients who need intervention. Alessandro Di Rocco, professor of neurology and chief of the Division of Movement Disorders at New York University School of Medicine and NYU Langone Medical Center said the large number of participants and long period over which they were tracked provides strong support for the findings.