Being stressed at work increases the risk of Parkinson's disease - but only in men

Being stressed at work increases the risk of Parkinson's disease - but only in men, new research suggests.

Men in demanding, time-pressured positions that they do not feel they have much control over are more at risk of the movement disorder, according to a Swedish study of more than two million people.

In contrast, women who feel they have control over their jobs are more likely to develop Parkinson's, the research adds.

The researchers believe women with too much control over their jobs may put in more overtime or take their work home with them, which can cause stress, according to Daily Mail.

 Previous studies suggests the stress hormone cortisol is higher in Parkinson's patients, which, along with genetic factors, may be behind the condition's onset.

How the research was carried out 

The researchers, analysed 2,544,748 people who were born between 1920 and 1950.

The participants' jobs were defined as stressful if they were demanding, such as those that require decision making, with employees having little control, for instance having no say over how their time is spent.

Over around 21 years, 21,544 of the participants were diagnosed with Parkinson's. 

Future studies should assess if jobs can protect against Parkinson's 

Results, further suggest that poorly-educated women who have a lot of control over their jobs are more at risk of Parkinson's.

This is unexpected given that control over a job is thought to somewhat cancel out its demands, which should supposedly reduce stress.

Men with demanding jobs that they have little control over are only more at risk of Parkinson's if they are educated, the study also found.

The scientists admit a drawback of the research is that they did not ask the participants how stressed they felt. Assessing stress via employment may vary between individuals depending on how they cope with challenging situations.

They add further studies should assess if a person's job can help to protect them against Parkinson's.  

Parkinson's patients have thinner retinas 

This comes after a breakthrough study released earlier this month suggested Parkinson's patients have thinner retinas.

According to the first research of its kind, the retinas of those with the movement disorder measure at 0.035mm compared to 0.037mm in non patients. 

Parkinson's patients are thought to have thin retinas due to the brain cells that produce the chemical dopamine dying.

Dopamine is responsible for coordinating movement. It also causes retinas to change shape in response to the light hitting them.

Study author Dr Jee-Young Lee, said: 'Our study is the first to show a link between the thinning of the retina and a known sign of the progression of the disease - the loss of brain cells that produce dopamine.

'These discoveries may mean neurologists may eventually be able to use a simple eye scan to detect Parkinson's disease in its earliest stages, before problems with movement begin.'