Drugs that lower cholesterol which are taken by millions of people could form the basis of new treatments for Parkinson's, research suggests.
Scientists found that certain types of statin drugs appear to offer some protection against the disease.
Patients who stopped taking fat-soluble statins such as simvastatin were 58% more likely to develop Parkinson's than those who stayed on them.
Fat-soluble statins were generally associated with a reduced risk of Parkinson's.
However, the same was not true for water-soluble versions of the drugs.
The findings, published online in the journal Neurology, come from a study of almost 44,000 people in Taiwan who were given statins to reduce cholesterol.
Under the Taiwanese health system, doctors have to stop prescribing statins once a patient's cholesterol falls to its target level. Study leader Dr Jou-Wei Lin, from National Taiwan University in Taipei, said: "This policy allowed us to see whether there was any difference in the risk of Parkinson's in people who stopped taking statins compared to the ones who kept taking them."
Dr Kieran Breen, from the charity Parkinson's UK, said people with Parkinson's should not treat themselves with statins unless advised to do so by their doctors.