Neuropsychological assessment in lamotrigine treated epileptic patients

A double-blind, placebo controlled cross over study assessed the efficacy of lamotrigine as adjunct therapy for patients with refractory partial seizures. In addition to the main study, a neuropsychological component evaluated three main areas of cognitive function. These included: i) Concentration and attention; ii) General Cerebral Efficiency, and iii) Mnestic functions--immediate, short term and new learning ability. Ten subjects (4 males, 6 females, age range 22 to 53, mean age 31.3 years) were involved in the study, each assessed 3 times--baseline, end of phase I and end of phase II. Whilst statistical analysis proved impracticable due to differing scores across cells, between the results of lamotrigine and placebo, clinically, there appeared to be a marginal reduction in General Cerebral Efficiency during the lamotrigine phase. In the light of these tests, the conclusion is advanced that lamotrigine does not specifically impair cognitive function, and that it does not impair mnestic function. An alternate hypothesis of interaction effects is posited for the slight reduction in speed of information processing.