Abstracts

A recent study evaluated the cognitive effects of lamotrigine (LTG) and topiramate (TPM) adjunctive therapy for refractory partial seizure disorders in adults. This analysis provides further examination of these results in patients over the age of 50. This randomized, double-blind clinical trial evaluated the cognitive effects of TPM and LTG in addition to the safety and tolerability of TPM and LTG in older adult patients with partial seizures., Eligible patients had a diagnosis of partial epilepsy and were inadequately controlled by a regimen containing carbamazepine (CBZ) or phenytoin (PHT). Patients were evaluated and administered six cognitive tests at each of the three study phases: Baseline; Escalation (8 weeks) to 500mg/day LTG or 300mg/day TPM; Maintenance (8 weeks). An endpoint of the study was change from Baseline in the scores from the six standardized measures of cognition to the end of the Maintenance Phase. Statistical testing was performed using analysis of covariance methods., The most common ([gt]=10%) treatment-emergent adverse events (AEs) were dizziness (12% LTG, 4% TPM) and nausea (16% LTG, 4% TPM). More patients in the TPM group prematurely discontinued due to an AE (35% TPM, 28% LTG). Two of the thirteen patients in the TPM group that prematurely discontinued due to cognitive decline were considered related (15%). Ten patients in the LTG group that prematurely discontinued due to cognitive decline were not related. Of the 192 patients (96 LTG, 96 TPM) enrolled in the study, there was a statistically significant difference in three of the six cognitive tests in favor of LTG (COWA p[lt]0.001, Stroop Test p=0.038, Symbol-Digit Modalities p[lt]0.001)., Although no significant discontinuation rate was found, treatment with LTG compared to TPM resulted in significantly better cognitive test scores in certain cognitive domains for older adult patients with epilepsy. This finding was consistent with the result reported previously from the overall population in this study., (Supported by GlaxoSmithKline Research and Development.)