Depression and anxiety are twice as common in people newly-diagnosed with Parkinson's disease compared with the general population, research suggests.

研究显示，抑郁和焦虑在帕金森综合症初诊患者中出现的几率是普通人群的两倍。

Writing in the journal Neurology, US researchers say depression increases in frequency in Parkinson's patients and is often left untreated.

Previous research suggests that the disease's impact on the brain can be a trigger for depression.

Parkinson's UK said depression could be due to a number of causes.

Researchers from the University of Pennsylvania School of Medicine examined 423 newly-diagnosed Parkinson's patients and tracked their mental health over two years.

At the outset, 14% of patients with Parkinson's disease were found to have depression, compared with 6.6% of a group of healthy volunteers.

During the follow-up, there was a small rise in the frequency and severity of depression in the group with Parkinson's, while in the control group a decrease was noted.

At the start of the study, 16% of patients with Parkinson's were taking an anti-depressant, and this increased significantly to 25% two years later.

But 65-72% of patients who screened positive for depression were still not being treated with medication, the study said.