People with Parkinson's Disease are known to be at a higher risk of malnutrition. The prevalence of malnutrition in Parkinson's Disease has been estimated to be up to 24%. Between 3% and 60% of people with Parkinson's Disease are reported to be at risk of malnutrition. To date, there is no clear explanation for malnutrition in these patients.
The aim of this study was to determine the prevalence of malnutrition and the factors that cause it. Of the patients they assessed, 55% of them were at risk of malnutrition, and 8% of them had already been malnourished. Age, Parkinson's Disease severity, off periods, depression and hypothyroidism were the factors most related to developing malnutrition. The dopamine agonist ropinirole was one of the factors that was most associated with a more favourable nutritional status.
Dopamine, whose deficiency causes Parkinson's Disease, is made from dietary substances, including vitamins, minerals and L-tyrosine, which is usually obtained from high protein foods. The deficiency of any of these nutrients could consequently lessen the amount of dopamine produced. The malnutrition that is common in Parkinson's Disease could therefore not only contribute to its onset but could worsen the symptoms over time even further.
Reference : Journal of Neurological Science  375 : 235-238 (S.Tomic, V.Pekic, Z. Popijac, T.Pucic, M.Petek, T.G.Kuric, S.Misevic, R.P.Kramaric)
Complete abstract : http://www.ncbi.nlm.nih.gov/pubmed/28320137