Abstracts

The current analysis evaluated changes in weight and body-mass index (BMI) in patients treated with lamotrigine in the presence and absence of concomitant valproate or antipsychotics., A post hoc analysis was conducted from a prospective, open-label study of lamotrigine in 1175 patients with bipolar I disorder designed to assess the rate of rash in patients with or without specific dermatological precautions. Lamotrigine was administered for 12 weeks, including a 5-week titration period (target dosage 200 mg/day). Weight and BMI was measured at baseline, week 5 and week 12 visits., Baseline weight was statistically significantly higher in patients taking concomitant valproate versus without (199.1 [plusmn] 49.07 versus 184.7 [plusmn] 47.53 lb, [italic]P[/italic] [lt] 0.0001) and was statistically significantly higher in patients taking concomitant antipsychotics versus without (192.7 [plusmn] 47.31 versus 186.1 [plusmn] 48.48 lb, [italic]P[/italic] [lt] 0.05). Statistically significant changes in weight were not observed between treatment groups. Weight changes from baseline to week 12 were -0.2 [plusmn] 6.82 lb with valproate, 0.0 [plusmn] 8.40 lb without valproate, -0.4 [plusmn] 7.99 lb with antipsychotics, and 0.0 [plusmn] 8.14 lb without antipsychotics ([italic]P[/italic][gt]0.05 for all group comparisons). Statistically significant changes in BMI were not observed between treatment groups. BMI changes from baseline to week 12 were 0.0 [plusmn] 1.07 with valproate, 0.0 [plusmn] 1.41 without valproate, -0.1 [plusmn] 1.34 with antipsychotics, and 0.0 [plusmn] 1.34 without antipsychotics ([italic]P[/italic][gt]0.05)., These results are consistent with previous findings that lamotrigine is weight neutral in patients with bipolar disorder and suggest that lamotrigine may be given to patients with concomitant medications that are frequently associated with increased body weight without causing additional weight gain., (Supported by GlaxoSmithKline.)