Negative Correlation Between Legume Consumption and Prodromal Parkinson’s Risk in Patients With REM Sleep Behavior Disorder
Previous studies have examined the relationship between diet and Parkinson’s in Western populations, but diet varies widely across geographies and ethnic groups, and the association has not been previously studied in Asian populations.
In a study published last month in Parkinsonism and Related Disorders, researchers evaluated the relationship between diet quality and prodromal Parkinson’s disease (pPD) probability in a population of Korean patients with polysomnography-confirmed isolated rapid eye movement (REM) sleep behavior disorder (iRBD), a strong predictor of Parkinson’s disease and other synucleinopathies.
pPD probability was measured in 101 patients with iRBD at the Neurology Department of Seoul National University Hospital using the Web-Based Medical Calculator for Prodromal Risk in Parkinsonism from the International Parkinson and Movement Disorder Society. Diet quality was assessed with the Recommended Food Score (RFS), which includes items with high levels of antioxidants.
RFS scores did not differ between the study population and age- and sex-matched controls. To examine differences in pPD probability based on RFS, participants were split into high and low RFS groups, however the probability score did not differ between the two groups (P=0.189). Given that the study population had iRBD, the authors posited that the statistical power of the analysis was reduced.
To overcome this, they examined the relationship between the number of prodromal markers (0-1, 2, or 3 or more of the following: hyposmia, excessive daytime sleepiness, depression, and constipation) and RFS food subgroup scores. Overall RFS did not differ between the groups, but legume consumption was significantly higher in those with 0-1 prodromal markers (P=0.016). Further, in patients ≤70 years old, legume consumption was associated with significantly lower pPD probability (P=0.032).
The authors note that the protective effect of legumes may be explained by their antioxidative properties, as oxidative stress has been shown to damage the substantia nigra in Parkinson’s, but caution that further studies would need to be conducted to demonstrate a causal relationship between legume consumption and prodromal Parkinson’s disease probability.
