Lamotrigine in bipolar disorder: results of a mirror-image evaluation using the NIMH Lifechart-Methodology

Lamotrigine (LTG) is characterized by prophylactic efficacy against bipolar depression (BPD). We evaluated retro- and prospectively the naturalistic treatment outcome with LTG analysing lifecharts of patients from the bipolar outpatient clinic.

Lifechart-data of 20 patients routinely treated with LTG for the first time were evaluated, comparing number and duration of manic, depressive and mixed episodes prior to LTG and after initiation of treatment (mirror-image evaluation). The mean prospective evaluation period based on the lifechart was 18.1 months. Also we compared the number and severity of "switches" from depression in mania. Additionally, CGI-BP, YMRS, IDS-C and GAF scores at the monthly visits were compared for time after LTG initiation.

We found no significant differences in the absolute number of manic, depressive and mixed episodes, respectively, before and after initiation of LTG. The number of "switches" did not differ significantly. A significant difference in duration of time patients suffered from a depressive state before and after initiation of LTG was observed in favour of LTG treatment (p=.006). A similar finding was observed for the time spent in mixed episodes (p<.001). No significant difference was observed for scores of mood scales at the monthly visits (CGI-BP, YMRS, IDS-C, GAF).

Generalizability of these results is limited due to the uncontrolled design and the issues in comparing prospective and retrospective data.

These data underline not only the antidepressant profile of LTG, but also the usefulness of the Lifechart-Methodology (LCM) in the evaluation of treatment outcome under routine conditions.