Effect of L-dopa therapy on plasma homocysteine levels and, consequently, on carotid ıntima-media thickness in Parkinson's disease patients

Abstract

Objective: In this study, we investigated hyperhomocysteinemia, as well as carotid intima-media thickness (CIMT) measurements using carotid Doppler ultrasonography, in Parkinson patients on levodopa treatment.

Methods: This study was carried out on 23 patients with Parkinson's disease and 21 age-and gender-matched healthy volunteers. Carotid Doppler ultrasonography was performed in order to determine CIMT in all cases. In addition, plasma homocysteine, vitamin B12 and folate levels were measured. Carotid Doppler ultrasonography and homocysteine levels were repeated one year later to evaluate the rate of atherosclerosis progression.

Results: Although the population sample was limited, there was an increase in baseline CIMT measurements that occurred in parallel with an increase in baseline homocysteine levels in these patients. At the end of the follow-up period, a bilateral increase in CIMT was observed, which was not correlated to hyperhomocysteinemia.

Conclusion: In conclusion, many clinical studies on hyperhomocysteinemia caused by L-dopa therapy in Parkinson patients have been published. However, the relationship between hyperhomocysteinemia and increased risk of vascular disease is still controversial. On the basis of this result, we speculated that hyperhomocysteinemia might lead to an increase in the arterial wall thickness, but its effect on the progression of atherosclerosis is still discussable.