Men who have higher levels of circulating uric acid (urate) may be less likely to develop Parkinson’s disease, possibly due to the protective role of urate in brain cells, researchers reported. The study, “Prospective study of plasma urate and risk of Parkinson disease in men and women,” was published in Neurology, the journal of the American Academy of Neurology.
Previous studies have suggested that urate, formed by the breaking down of chemicals called purines — found in foods — might have a protective effect in brain cells. Researchers investigated if higher plasma urate concentrations were associated with a lower risk of developing Parkinson’s disease (PD), and if the significance of the PD-urate relationship varied according to gender.
The study included 90,214 participants in three ongoing trials, with urate levels were measured through blood samples. During the study, the scientists identified 388 new PD cases (202 men and 186 women), who were then matched to 1,267 controls (no PD). The urate levels results were adjusted to include factors such as age, smoking and caffeine intake, and the relative risks were calculated.
Results showed that urate levels in men varied from a low of less than 4.9 mg/dL to a high of 6.3 to 9.0 mg/dL (normal range was 3.5 to 7.2 mg/dL). Men with high levels of uric acid were about 40 percent less likely to develop Parkinson’s than those with low levels. Among men who developed PD, 45 had high urate levels and 58 had low levels. In comparison, 111 men in the non-PD group had high levels of urate and 107 had low levels. Among women, no relationship was found between plasma uric acid levels and the risk of developing PD.
Although researchers note that the study does not prove a protective effect of high urate levels against PD, it does show an association consistent with a lower risk. If the results are confirmed in future trials, however, the association could constitute a promising therapeutic approach, as a careful and appropriate rise of urate blood levels can be easily and inexpensively done.
Study author Xiang Gao, MD, PhD, of Pennsylvania State University in University Park, said in a press release, “These results suggest that urate could protect against Parkinson’s or slow the progression of the disease in its very early stages before symptoms are seen. The findings support more research on whether raising the level of urate in people with early Parkinson’s may slow the disease down.”