A new study has found a link between depression and Parkinson's disease. Researchers say that depression triples the risk of developing Parkinson's disease later in life.

Recently a research found that midlife stress can lead to dementia. Now, another study by scientists in Taiwan found that people with depression can develop Parkinson's disease, a condition where people lose their ability to control movement.

"Depression is linked in other studies to illnesses such as cancer and stroke," said Albert C. Yang, Taipei Veterans General Hospital in Taipei, Taiwan. "Our study suggests that depression may also be an independent risk factor for Parkinson's disease." Yang is one of the study authors.

Parkinson's disease occurs when the part of the brain that controls movement stops functioning properly. This usually happens when the neurons that produce the movement controlling chemical 'dopamine', die. The condition usually affects men more than women. Although the disease starts after 60 years of age, stress could trigger an early onset.

An estimated 500,000 people in the U.S suffer from the condition. Currently, there is no cure, but a variety of medications provide dramatic relief from the symptoms, according to National Institute of Neurological Disorders and Stroke.

The study was based on data from over 23,000 people of which 4634 had depression. Researchers looked at Parkinson's disease risk in people with and without depression. They found that those who suffered from depression had 3.24 times higher risk of developing Parkinson's 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 in a news release. "Our study also found that depression and older age and having difficult-to-treat depression were significant risk factors as well."

The study is published in the journal Neurology.

According to data from Centers for Disease Control and Prevention (CDC), about one in every ten adults in the country is depressed.