Event related evoked potentials in dementia: role of vitamin E.

Dementia is a common cognitive syndrome reflecting a wide spread chronic progressive disease as an extension to normal aging process. Oxidative stress has been implicated in dementia and antioxidants have become attractive therapeutic agents. Among the antioxidants vitamin E is the most potent in the treatment of dementia. Study was conducted in 20 patients suffering from dementia in the age group of 66-74 and in 20 age and sex matched controls. Latency of the P3 component of event related evoked potential (ERP) showed an increase from 338.65 +/- 42.22 msec in control group to 348.9 +/- 46.38 msec in patients of dementia. In control group P3 latency decreased from 338.65 +/- 42.22 msec to 331.6 +/- 38.75 msec after Vitamin E therapy. In patients of dementia latency decreased significantly from 348.9 +/- 46.38 msec to 324.62 +/- 44.25 msec after vitamin therapy for one month. P3 amplitude in controls and demented was 7.2 +/- 3.62 mu v and 7.07 +/- 3.73 mu v respectively. After vitamin E therapy a statistically significant increase in amplitude (P < 0.05) was observed in controls (9.34 +/- 5.04 mu v) and in patients of dementia (9.58 +/- 5.24 mu v). The study suggests that the latency and amplitude of P3 were not significantly different in control and dementia patients, while vitamin E supplementation (oral 800 mg per day for 30 days) decreased the latency and increased the P3 amplitude in both the control and dementia patients. Our study further supports that Vitamin E supplementation, because of its antioxidant property might be decreasing oxidative stress, which may lead to improvement in cognitive pool of generator neurons of P3.