Nutritional traits in the prodromal phase on Parkinson's disease in community-dwelling older adults in Japan

The growing aging population means that increasing numbers of people are living with Parkinson’s disease (PD). Although dopamine replacement is effective, there are currently no curative or disease-modifying treatments. Nutrition is a well-known environmental risk factor of PD. This study aimed to clarify the relationship between nutritional traits and the prodromal phase of PD. Subjects were enrolled from community-dwelling older adults. To identify individuals with prodromal PD (PPD), probability of PPD (PPP) and mild parkinsonian sign (MPS) assessments were used. Nutritional status was evaluated using a self-administered food frequency questionnaire form. Intakes of total energy, the three major nutrients (fat, protein, and carbohydrate), B vitamins, water, and dietary fiber were calculated. Nutrient intake in PPD was analyzed using analysis of covariance with age and sex as covariates. We enrolled 305 subjects. The prevalence of older adults living with PPD was 4.1% by PPP ≥ 0.3 and 21.0% by MPS criteria. Compared with subjects without PPD, individuals with PPP ≥ 0.3 had significantly higher fat intake (33.4 ± 8.8 vs. 29.3 ± 6.7 g/1000 kcal/day, p=0.037) and lower carbohydrate intake (121.4 ± 19.0 vs. 132.1 ± 17.7 g/1000 kcal/day, p=0.039), and MPS-positive subjects had significantly lower total energy intake (1817.5 ± 384.7 vs. 1933.7 ± 433.7 kcal/day, p=0.012). In this community-based cross-sectional study, nutritional traits differed between older individuals with and without PPD; these differences were more pronounced when the PPP was used to evaluate PPD. Nutrition and diet may thus modify PD incidence. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement This study was supported by Grants-in-Aid from the Japan Agency for Medical Research and Development (JP21dk0207053 and JP21gm1010002). ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: Ethics committee of Iwate Medical University gave ethical approval for this work I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes All data produced in the present study are available upon reasonable request to the authors