Highly educated physicians are more likely to develop Parkinson’s disease than manual workers who left school early, a new study has shown. The findings suggest a link between education and occupation and the risk of Parkinson’s. But the US scientists who made the discovery warn that the results should be treated with caution. While they reflected an association, this did not necessarily mean there was a causal connection. The researchers examined the medical records of everyone in Olmsted County, Minnesota, who developed Parkinson’s from 1976 to 1995. Olmsted County is the home of the Mayo Clinic, where the research was based. The scientists found the highest levels of Parkinson’s disease risk in people with nine or more years of education. The degree of risk was seen to rise with additional years of schooling. Among different occupations, physicians were most at risk among the general population. People in active, manual jobs such as construction and factory workers had the lowest risk. No clear explanation for the trend has yet been found. Investigator Dr Roberta Frigerio said: “Our findings for education and occupation are complex, and therefore they need to be interpreted with care. These factors may be surrogates for a variety of exposures - physical activity, personality or socio-economic status. Further studies are needed to interpret our findings.” Fellow researcher Dr Demetrius Maraganore said: “We really can’t say from this study that education and occupation are causal factors in Parkinson’s disease, we can only say that they are associated.
