Depression can sometimes triple the risk of developing Parkinson's disease, researchers found in a new study.
Statistics show that one in every four Americans, accounting for 26.2 percent of the country's population, suffers from mental disorders, depression being the most common disorder. Major Depressive Disorder is the leading cause of disability in the U.S. for ages 15-44, affecting approximately 14.8 million American adults.
Previous studies have linked depression to many diseases like strokes, cancer and other health issues. In a new study, researchers found another negative attribute of depression. Researchers from Taipei Veterans General Hospital in Taipei found that depression also increases the risk of developing Parkinson's disease by three times.
For the study, lead author Albert C. Yang, MD, PhD, with Taipei Veterans General Hospital in Taipei, Taiwan and his team examined the medical records of 4,634 people with depression and 18,544 without depression for 10 years. They also looked into the risk of developing Parkinson's disease among the participants, excluding the ones that were already diagnosed with the disease within two to five years of being diagnosed with depression.
During the 10 years of the study, 1.45 percent of participants with depression (66 participants) and 0.52 participants without depression (97 participants) were diagnosed with Parkinson's disease. From this observation, researchers concluded that people with depression were 3.24 times more likely to develop Parkinson's disease than people without the disorder.
Researchers are yet to determine the cause of this increase in risk factor. They are still not sure whether depression causes the disease or is actually an early symptom of the disease.
"Many questions remain, including whether depression is an early symptom of Parkinson's disease rather than an independent risk factor for the disease," Yang said. "Our study also found that depression and older age and having difficult-to-treat depression were significant risk factors as well."
