Effectiveness of quetiapine plus lamotrigine maintenance therapy in challenging bipolar disorder patients

ObjectiveAssess quetiapine plus lamotrigine (QTP + LTG) combination maintenance therapy effectiveness in challenging bipolar disorder (BD).MethodOutpatients assessed with the Systematic Treatment Enhancement Program for Bipolar Disorder (STEP-BD) Affective Disorders Evaluation and followed with the STEP-BD Clinical Monitoring Form were naturalistically prescribed QTP + LTG.ResultsFifty-four outpatients with challenging BD, taking in addition to QTP + LTG, a mean ± SD of 2.1 ± 1.6 (in 63.0% at least 2) other psychotropic and 2.3 ± 1.9 non-psychotropic prescription medications, had QTP + LTG maintenance trials. Median(mean ± SD) QTP + LTG duration was 401(730 ± 756) days. Final QTP and LTG doses were 87.5(188 ± 211) and 300(287 ± 108) mg/day, respectively. Half (27/54) of patients discontinued QTP (in 19), LTG (in 6), or QTP + LTG (in 2), after 294(415 ± 414) days - due to side-effects in 10, inefficacy in seven, non-adherence in five, and other reasons in five. 42.6%(23/54) had additional pharmacotherapy intervention for emergent mood symptoms, after 175(261 ± 237) days, with at least one psychotropic added (in 16/54) or substantively (by ≥ 50%) increased (in 7/54). 55.6%(30/54) had recurrent mood episodes, after 126(187 ± 158) days, most often depressive (in 35.2%), although 64.8%(35/54) were euthymic at final visit taking QTP + LTG. Sedation increased significantly during treatment among those with side-effect discontinuations, and 19.2%(10/52, all having QTP added to LTG) had clinically significant (≥ 7%) weight gain.LimitationsNo placebo comparison group. Small sample of predominantly female Caucasian insured outpatients taking complex concurrent medication regimens.ConclusionAdditional studies are warranted to confirm our preliminary observation that QTP + LTG maintenance may be effective in patients with challenging BD.