PEOPLE who are not religious are at a tenfold higher risk of developing Parkinson’s disease in later life than those who see religion as important in their lives, a study has found.

Parkinson’s is the fastest growing neurological disorder in the world, and cases are predicted to double in the next two decades as populations age. In the UK, 145,000 people have the disease, for which there is no cure.

A study by researchers at the University of Birmingham has found evidence for the first time that people who are not religious have an increased risk of developing the disease. Those who said that they had a spiritual, but not religious, outlook on life were also observed to be at higher risk.

Researchers measured a person’s religiosity by asking how important religion was in their daily lives, on a scale of “Very important” to “Not at all important”. The same question was asked about spirituality.

The study followed almost 10,000 people from the UK and the United States for a decade. Researchers found that those who rated religion as not at all important in their lives had a tenfold risk of developing the disease. There was a relationship between decreasing religious adherence and increasing risk of disease.

People who considered spirituality very important, but not religion, were also at high risk of developing Parkinson’s.

Other studies of brain scans in people with Parkinson’s have found that brain lesions that cause the disease intersect with regions of the brain associated with religiosity.

Parkinson’s is a progressive condition that kills cells that produce dopamine. The chemical acts as a messenger to control movement, and a deficiency makes sufferers prone to uncontrollable shaking.

But, writing in the Journal of Religion and Health, the researchers said: “Engagement in religious activities could modify dopamine levels in brain regions linked to Parkinson’s.”

Researchers noted, however, that previous studies had shown that clergy and religious workers had a higher risk of developing Parkinson’s than the general population.

“The most parsimonious explanation for this observation would be that the increased risk for PD is confined to individuals with a religious occupation who subsequently experience a decline in religiosity,” they said.