Abstracts

Rationale: A high proportion of patients experiences topiramate (TPM)-related weight loss. The present study examined the process of weight change and identified the predictors and inhibitors (BMI, intellectual level, TPM titration speed) of weight loss with TPM. Methods: We conducted a prospective, uncontrolled clinical trial for 108 adults with epilepsy who were treated with TPM. Before prescribing TPM, we informed patients and caregivers about TPM-related weigh loss. Weight and body mass index (BMI) were evaluated at the following time-points: before starting TPM, at 1 month, at 6 months, at 12 months and at 18 months. Slower titration group is taken 50 mg TPM in 2 week and Faster titration group is taken 100mg TPM in 2 week. Plasma levels of TPM and level-to-dose ratio (g/ml/mg/kg) were calculated at 12 months. The intelligence quotient (IQ) was assessed according to ICD-10 criteria based on WAIS-? or Suzuki-Binet Intelligence Tests prior to TPM administration. Results: A total of 78 patients completed 18 months of TPM treatment. The weight loss occurred over a 12-month period, where the weight rapidly decreased during the initial 6 months and then stabilized gradually over time. Weight loss at 1 month can predict body loss at 12 and 18 months. Losing 1% body weight or 1kg at 1 month was the risk factor of significant weight loss. Weight loss at 1 month did not correlate with TPM titration speed. The percentage of weight loss at 18 months correlated most strongly with IQ levels (߽0.284, p = 0.002) but did not correlate with baseline BMI. Conclusions: Our results suggest that weight loss begins within 1 month of TPM administration, and may continue for at least 1 year. The pattern of weight loss differs according to IQ, with higher IQ patients experiencing greater weight loss during continued therapy. This may be clinically plausible because lower IQ patients are helped more adequate dietary intake by caregivers. Funding: None