Effect of Homocysteine Levels on Cognitive and Motor Performance in Patients with Parkinson's Disease

Objective: As well as being a risk factor for vascular diseases, hyperhomocysteinemia is also a risk factor for neurodegeneration. The present study examines the effect of hyperhomocysteinemia on cognitive and motor performance in patients with Parkinson’s disease (PD). Material and Methods: 46 PD patients monitored by us and 30 volunteers without a cronic disease to cause hyperhomocysteinemia compatible with this population were included in the study. Blood levels of folate, vitamin B12 and homocysteine of both groups were measured and compared. In the patient group, Standardized Mini Mental Test (SMMT) and The Unified Parkinson’s Disease Rating Scale (UPDRS) scores were determined and serum homocysteine levels were measured to see if there was a correlation between these two. Furthermore, the effect of levodopa intake on blood vitamin B12, folate and homocysteine levels in patients was examined. The assumed significance level is p <0.05. Results: Vitamin B12 and folate levels were significantly lower in the patient group than in the control group, whereas homocysteine levels were significantly higher in the patient group. Levodopa intake had no significant effect on the examined levels. Elevated homocysteine levels resulted in lower SMMT scores and higher UPDRS scores. Conclusion: Many other studies have found hyperhomocysteinemia in PD patients and indicated that hyperhomocysteinemia was one of the causes of decreased cognitive and motor performance during the course of disease. With its finding of decreased performance in the patients, the present study also supports the above mentioned studies and recommends B12 and folate supplements in order to slow down the disease progression.