Efficacy and Tolerability of Lamotrigine in Borderline Personality Disorder: A Systematic Review and Meta-Analysis

Background: Patients with Borderline Personality Disorder (BPD) have a high prevalence of mood disorders. Lamotrigine (LAM) is often used as an off-label therapeutic option for BPD. We aimed to conduct a systematic review and meta-analysis to assess the efficacy and tolerability of LAM for the treatment of BPD. Methods: We comprehensively searched electronic databases for eligible studies from the inception of databases to September 2019. Outcomes investigated were BPD dimensions, tolerability, and adverse events. Quality assessments were completed for the included studies. Data were summarized using random-effects model. Results: Of the 619 records, five studies, including three randomized controlled trials (RCT; N = 330) were included for the qualitative analysis. A meta-analysis conducted on two RCTs measuring LAM efficacy at 12 weeks, showed no statistically significant difference at 12 weeks (SMD: -0.04; 95% CI: -0.49, 0.41; p = 0.87; I2 = 38%) and at study endpoints (SMD: 0.18, 95%CI: -0.89, 1.26; p = 0.74; I2 = 86%) as compared to placebo. Sensitivity analysis on three RCTs measuring impulsivity/aggression showed no statistically significant difference between LAM and placebo (SMD: -1.84, 95% CI: -3.94, 0.23; p = 0.08; I2 = 95%). LAM was well tolerated, and quality assessment of the included trials was good. Conclusions: Our results suggest there is limited data regarding efficacy of lamotrigine in BPD. There was no consistent evidence of lamotrigine's efficacy for the core symptom domains of BPD. Future studies should focus on examining targeted domains of BPD to clarify sub-phenotypes and individualized treatment for patients with BPD.