Serum levels of vitamin A in Parkinson's disease

To elucidate a possible role of vitamin A in the pathogenesis of Parkinson's disease (PD) we compared serum levels of retinol (vitamin A), measured by HPLC, and the vitamin A/retinol binding protein (RBP) ratio of 42 PD patients (22 males and 20 females, mean age 67.3 +/- 1.34 years) and their respective spouses as control group (20 males and 22 females, mean age 66.2 +/- 1.42). The serum levels of vitamin A did not differ significantly between the 2 groups (0.59 +/- 0.03 microgram/dl for PD patients and 0.57 +/- 0.03 microgram/dl for controls), nor did the vitamin A/RBP ratio (0.87 +/- 0.04 and 0.82 +/- 0.03, respectively). There was no influence of antiparkinsonian therapy on vitamin A or vitamin A/RBP ratio. Serum levels of vitamin A, and vitamin A/RBP ratio did not correlate with age, age at onset, scores of the Unified Parkinson's Disease Rating Scale or the Hoehn and Yahr staging in the PD group. These results suggest that serum concentrations of vitamin A, do not play a role in the pathogenesis of PD.