The Clinical Effectiveness and Cost-Effectiveness of Lamotrigine in Borderline Personality Disorder: A Randomized Placebo-Controlled Trial
Crawford, M. J., Sanatinia, R., Barrett, B., Cunningham, G., Dale, O., Ganguli, P., Lawrence-Smith, G., Leeson, V., Lemonsky, F., Lykomitrou, G., Montgomery, A. A., Morriss, R., Munjiza, J., Paton, C., Skorodzien, I., Singh, V., Tan, W., Tyrer, P., Reilly, J. G., & LABILE study team (2018). The Clinical Effectiveness and Cost-Effectiveness of Lamotrigine in Borderline Personality Disorder: A Randomized Placebo-Controlled Trial. The American journal of psychiatry, 175(8), 756–764. https://doi.org/10.1176/appi.ajp.2018.17091006
This article by Crawford et al. provides a fascinating look at the use of medications, particularly lamotrigine, in treating borderline personality disorder (BPD). First, let's get a bit of background on the topic.
So, what is a personality disorder? Everyone has a personality, which is shaped by a variety of genetic factors and life experiences. In a way, a personality is how we see ourselves and how we interact with the world around us. Inherently, a personality is only really evident when we are with other people. Arguably, if we lived alone on a deserted island, our personality wouldn’t have much impact.
Borderline personality disorder is a broad psychiatric diagnosis thought to originate from adverse developmental experiences, genetics, and temperament. It is a psychiatric masquerader, characterized by significant heterogeneity (meaning variety) even within the diagnosis. No two people with BPD are really the same. It is also often misdiagnosed as bipolar disorder, ADHD, or other illnesses. Sometimes, people think the diagnosis is not helpful because it is so broad. However, we know that there is a cluster of symptoms and behaviors that consistently group together in this way. The good news is that BPD actually has a relatively good remission rate, and it can be very rewarding to work with. Unfortunately (or fortunately), medication has traditionally been ineffective in treating BPD. This hasn’t stopped us from prescribing, perhaps because we need to improve our therapy skills, or because it is hard to see a patient suffering and prescribing makes us feel like we are doing something to help.
This study looks at lamotrigine (a common mental health medication usually used in mood disorders) and whether it works in borderline personality disorder. The initial thought was that bipolar mood fluctuations might overlap with the emotional instability of BPD, so this medication might help.
The researchers recruited people over 18 who had already been diagnosed with BPD. Anyone with co-occurring bipolar disorder was excluded to ensure that the study did not inadvertently treat that illness. They found 276 people (a substantial number) and divided them into groups to receive either the medication or a placebo (fake drug). The patients, doctors, and everyone involved were not told if the medication was real or fake. They were observed for one year.
At the one-year mark, only about 40% of patients continued taking the medication. Interestingly, there was NO DIFFERENCE between those who took the active medication and those who took the placebo. There was also no difference in adherence or side effects between the two groups.
Overall, the study reinforced that lamotrigine is not an effective medication for BPD. However, it still has its role in treating bipolar disorder, and these two conditions can often be confused and mixed up. It is essential to have a thorough discussion with your psychiatrist, combining patient and carer interviews and various scales, to ensure the diagnosis and treatment are correct.