Poor adherence to depression treatment is common. Understanding determinants of poor adherence to therapy is crucial to ensure optimal clinical outcomes. The aim of this study was to describe characteristics of dosing history in participants with depression receiving once daily escitalopram. Participants were randomly assigned to interpersonal psychotherapy (IPT) or pharmacotherapy. Participants assigned to IPT who did not evidence a response or remission had escitalopram added to their treatment. Adherence to pharmacotherapy was assessed using an electronically monitored pill cap (MEMS). Fifty-four participants on escitalopram alone and 32 on escitalopram+IPT were monitored. After 200 days, 71.7% of the participants in the escitalopram group and 54.8% of those in the escitalopram+IPT group were still engaged with the dosing regimen. Of those engaged in the dosing regimen, 17.9% (average over 210 days) of the participants did not take their medication (nonexecution). In 69% of the days participants took the correct dosage required. On average, participants had three drug holidays and the mean length of a holiday was 7 days per patient. No difference in adherence patterns was observed between patients receiving escitalopram alone vs. IPT+escitalopram. Early discontinuation of treatment and suboptimal daily execution of the prescribed regimen are the most common facets of poor adherence in this study population.
aDepartment of Medicine, Division of Clinical Pharmacology, Indiana University School of Medicine, Indianapolis, Indiana
bDepartment of Pharmaceutical Sciences, School of Pharmacy
cSchool of Medicine
dDepartment of Psychiatry, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
eCentre for Addiction and Mental Health, University of Toronto, Toronto, Ontario, Canada
fAARDEX Group Ltd., Sion, Switzerland
gDepartment of Biostatistics, University of Liege, Liege, Belgium
Trial Registration: Trial registration Number: NCT00073697.
Correspondence to Alette M. Wessels, PhD, Department of Medicine, Division of Clinical Pharmacology, Indiana University; 1001 W. 10th St. WD Myers Bldg. W7125; Indianapolis, IN 46202, USA Tel/fax: +1 317 276 9502; e-mail: firstname.lastname@example.org
Received March 15, 2012
Accepted August 17, 2012