Abstracts

Rationale: Patient satisfaction, convenience of dosing, and tolerability may impact adherence to a medication regimen. For patients with depression, Cramer (1998) reported a mean rate of adherence of 65% to the medication regimen. Reported rates of adherence among those with bipolar disorder are as low as 35% (Colom, 2000). Treating epilepsy and psychiatric illness with traditional orally ingested medications may be a challenge for individuals who are unable to or have difficulty swallowing pills. Difficulty swallowing medication may affect attitudes towards medication and adherence, and is highly underreported (Manjunath, 2008). The primary objective of this study was to measure convenience for a lamotrigine orally disintegrating tablet (LGT ODT) formulation of lamotrigine versus the conventional lamotrigine immediate release tablet (LTG IR)in patients prescribed lamotrigine for treatment of mood disorders. Methods: Psychiatrically and medically stable patients (N= 97, mean age 41, 97% Caucasian) on a maintenance dose (mean dose 261 mg/day) of LTG IR were switched to equivalent dose LTG ODT for 3 weeks. Primary outcome was change from baseline on the Convenience subscale of the Treatment Satisfaction Questionnaire for Medication (TSQM), a validated measurement of satisfaction and convenience with medication treatment. Study participants were outpatients with a diagnosis of a mood disorder who reported difficulty swallowing medication. The TSQM was administered at baseline and after taking LTG ODT for 3 weeks. Patient’s, and caregiver’s preference, adherence with treatment, and measures of effectiveness were also collected. Results: Patients reported significant improvement with convenience of taking medication as demonstrated by TSQM mean convenience score increase from 59.8 while on LTG IR to 83.0 (change = 23.3, p<0.001). TSQM satisfaction scores remained high while taking both formulations (LTG IR= 76.3, LTG ODT = 76.0). Significantly more patients reported that they were more adherent on LTG ODT (89%, p<0.001), and significantly more patients stated that they preferred LTG ODT to LTG IR (74%, p <0.001). Companion/caregivers concurred with patient’s preference (LGT ODT 81%, p<0.001). Common adverse events were; headache (5%), anxiety (3%), depression (3%), hypomania (3%), nausea (2%). Clinical Global Impression-Severity, and Beck Depression Inventory scores remained consistent.