Topiramate tied to weight loss vs other antiseizure drugs

Among commonly used antiseizure medications (ASMs), topiramate appears to result in weight loss at 6 and 12 months under either initiation and subsequent adherence or initiation-only effects, reports a study. Other ASMs seem to contribute to greater weight change.

A total of 52,309 adult patients who initiated ASMs were included in the analysis. The investigators applied a target trial emulation approach to control time-varying confounding and selection bias. They also explored the long-term comparative impacts on weight change following initiation and adherence to different ASMs at 6 and 12 months postinitiation.

Topiramate was the most initiated ASM (41.2 percent). Weight change at 6 months was higher under initiation and adherence to levetiracetam (0.94 kg, 95 percent confidence interval [CI], 0.20‒1.64), lamotrigine (1.44 kg, 95 percent CI, 0.74‒1.99), valproate (2.42 kg, 95 percent CI, 1.71‒2.88), carbamazepine (1.32 kg, 95 percent CI, 0.46‒2.16), and oxcarbazepine (1.74 kg, 95 percent CI, 0.85‒2.71) compared with topiramate.

Similar results were observed at 12 months and in sensitivity and subgroup analyses. The findings were primarily driven by weight loss associated with the use of topiramate rather than weight gain with the use of other ASMs. Notably, the findings were comparable but attenuated when accounting for medication initiation only.

“These results provided important information to help with decision-making regarding ASM initiation,” the investigators said.