Abstracts

Weight gain is a possible side-effect associated with the use of topiramate therapy. However one cannot predict which patients may develop weight loss, or how long the weight loss may continue. We followed serial weights in patients on topiramate for at least 1.5 years to determine if any pattern of weight loss was present. Patients at the Penn State Milton S. Hershey Medical Center that were placed on topiramate were offered participation in the study. Patients were required to agree to having weights checked at every visit for at least 1.5 years or longer. Exclusion criteria included patients already on topiramate at the time of referral to our center. A total of 195 patients were receiving topiramate therapy during the time of the study. Thirty patients were excluded due to already being on topiramate (TPM) therapy. Another 35 patients were excluded because they did not reach 1.5 years of therapy. This left 130 patients for evaluation. Of this group, 32 patients demonstrated weight loss while on TPM therapy. The average weight at the time of TPM initiation was 195 pounds (lbs). The average maximum weight loss was 32% of start weight and occurred at an average of 25 months, with a range of 4-84 months. The average weight at the end of the study was 22% of the start weight after a mean follow up time of 3.87 years with a range of 1.5 - 8 years. Only 3 patients discontinued therapy due to weight loss, doing so before the 1.5 year time. Topiramate therapy was associated with weight loss in 25% of our patient population. Average follow-up time was 3.87 years. Most patients showed a maximal weight loss within 25 months of onset of TPM therapy, with a tendency to then re-gain some of the weight lost. The average maximum weight loss was 32% of initial weight. However, at the end of the study, the average weight loss was only 22% of the initial body weight.