Variability of erythrocyte and serum lithium levels correlates with therapist treatment adherence efforts and maintenance treatment outcome

This study investigated the relationship between psychotherapeutic interven tions and pharmacologic measures of pharmacotherapy treatment adherence in patients with bipolar I disorder, as well as the relationship between these measures and treatment outcome. Subjects were participating in an ongoing maintenance treatment study. Audiotaped therapy sessions were rated for fre quency of psychotherapeutic interventions related to pharmacotherapy treatm ent adherence. Pharmacologic measures of medication adherence were compared to the tape ratings Its well as to treatment outcome. Variability in log e rythrocyte (RBC) lithium-a marker of probable nonadherence to the pharmacot herapy regimen-for individual patients correlated significantly with treatm ent adherence interventions scale ratings. This marker of nonadherence was significantly related to maintenance treatment outcome, as was variability of the serum lithium level/dose (L/D) ratio; however, no relationship was f ound between treatment adherence interventions scale ratings and outcome. [ Neuropsychopharmacology 24:192-197, 2001] (C) 2000 American College of Neur opsychopharmacology. Published by Elsevier Science Inc.