The use of electronic monitoring (MEMS®) to evaluate antipsychotic compliance in outpatients with schizophrenia
Introduction
Antipsychotic medications represent the cornerstone of treatment programs for individuals with schizophrenia. Unfortunately though, the effectiveness of these drugs is often compromised by noncompliance, a significant factor in both relapse and rehospitalization (Knapp et al., 2004, Robinson et al., 1999, Weiden et al., 2004). While the newer ‘atypical’ antipsychotics have been associated with a number of clinical advantages, including improved tolerability, noncompliance rates remain high (Dolder et al., 2002, Gilmer et al., 2004, Menzin et al., 2003). This is perhaps not so surprising given the evidence that noncompliance is a complex issue, influenced by a number of variables (Fenton et al., 1997, Weiss et al., 2002).
Several factors complicate the study of noncompliance. For example, individuals may not be forthcoming in providing this information, which could contribute to the wide range in estimates reported for compliance with antipsychotic treatment (Young et al., 1986). Different strategies have been used to improve accuracy of reporting (e.g., biologic markers, pill count), each with their own limitations (Blackwell, 1989, Cramer and Rosenheck, 1998). More recently, efforts to provide greater objectivity in measuring noncompliance have led to the development of electronic monitoring devices such as the Medication Event Monitoring System ([MEMS®], Aprex Corp., Fremont, Calif.), a medication bottle cap with a microprocessor that records the occurrence and time of each bottle opening (Cramer et al., 1989, Kruse and Weber, 1990). Considered by many to be the gold standard in evaluating compliance, these devices have been used in the study of various psychiatric and medical disorders (Bies et al., 2002, Bova et al., 2005, de Klerk, 2001, Leopold et al., 2004, McKenney et al., 1992, Shemesh, 2004).
There are now a small number of published reports that have used MEMS® in individuals with schizophrenia or schizoaffective disorder (Byerly et al., 2005, Diaz et al., 2001, Diaz et al., 2004, Nakonezny and Byerly, 2006). One report linked poor compliance (i.e., less than 50%), with increased hospitalization rates (Diaz et al., 2001), while a second study employing MEMS® demonstrated that clinicians dramatically underestimate compliance (Byerly et al., 2005). Two investigations using MEMS® have reported comparable compliance rates for typical and atypical antipsychotics (Diaz et al., 2004, Nakonezny and Byerly, 2006). Drawing upon the existing literature on compliance, our objectives were twofold. First, we were interested in comparing rates of compliance/noncompliance, as measured by MEMS® versus other evaluation techniques (e.g., self-report, clinician rating, pill count). Second, we wanted to examine the relationship between compliance/noncompliance, defined here by the MEMS® data, and various factors that have been identified as influencing compliance (e.g., side effects, insight).
Section snippets
Subjects
Patients were recruited from the Schizophrenia Program at the Centre for Addiction and Mental Health, a teaching hospital affiliated with the University of Toronto, Toronto, Canada. The program employs a case management system and follows several thousand individuals in both inpatient and outpatient settings. The study was approved by the Research and Ethics committee of the university.
Psychiatrists in the program provided study referrals, and inclusion criteria included the following: a)
Results
A total of 60 potential subjects were evaluated, of which 53 agreed to participate. One did not return the medication bottle with the MEMS® cap at follow-up and was subsequently excluded from the data analysis. Demographic data for the study sample (N = 52) were as follows: 26 males, 26 females; age (mean, SD) 36 ±10.3 years (range 19–55); education 13.2 ± 2.2 years (range 9–18); marital status — single (89%), married (11%); diagnosis — schizophrenia (67%), schizoaffective (33%); length of illness
Discussion
Using MEMS®, noncompliance with antipsychotic medication was 52% when viewed as a dichotomous variable, in line with a reported value of 48% in the one other study that used a threshold approach (in their case, 70%) to evaluate a somewhat similar population (Byerly et al., 2005), but in marked contrast to the 3% reflecting self-report or even the 22% estimated by the treating clinicians in our sample. The discrepancy between self-report and clinician estimates of compliance has been reported
Acknowlegments
We gratefully acknowledge the patients for their participation in this project.
References (49)
- et al.
Evaluating the consistency of pharmacotherapy exposure by use of state-of-the-art techniques
Am. J. Geriatr. Psychiatry
(2002) - et al.
A comparison of electronic monitoring vs. clinician rating of antipsychotic adherence in outpatients with schizophrenia
Psychiatry Res.
(2005) - et al.
Electronically monitored adherence in outpatients with schizophrenia or schizoaffective disorder: a comparison of first- vs. second-generation antipsychotics
Schizophr. Res.
(2006) Subjective response to neuroleptics in schizophrenia
Schizophr. Bull.
(1993)A rating scale for drug-induced akathisia
Br. J. Psychiatry
(1989)The content and context of compliance
Int. Clin. Psychopharmacol.
(1995)- et al.
Contributions to Neuropsychological Assessment
(1994) Compliance — measurement and intervention
Curr. Opin. Psychiatry
(1989)- et al.
Use of electronic monitoring devices to measure antiretroviral adherence: practical considerations
AIDS Behav.
(2005) - et al.
Targeted maintenance treatment in schizophrenia: issues and recommendations
CNS Drugs
(1996)
Continuous versus targeted medication in schizophrenic outpatients: outcome results
Am. J. Psychiatry
Compliance with medication regimens for mental and physical disorders
Psychiatr. Serv.
How often is medication taken as prescribed? A novel assessment technique
Jama
Insight and psychosis
Br. J. Psychiatry
Patient compliance with enteric-coated weekly fluoxetine during continuation treatment of major depressive disorder
J. Clin. Psychiatry
Use of the Medication Event Monitoring System to estimate medication compliance in patients with schizophrenia
J. Psychiatry Neurosci.
Adherence to conventional and atypical antipsychotics after hospital discharge
J. Clin. Psychiatry
Antipsychotic medication adherence: is there a difference between typical and atypical agents?
Am. J. Psychiatry
Determinants of medication compliance in schizophrenia: empirical and clinical findings
Schizophr. Bull.
Structured Clinical Interview for DSM-IV Axis I Disorders (SCID-CV)
Adherence to treatment with antipsychotic medication and health care costs among medicaid beneficiaries with schizophrenia
Am. J. Psychiatry
Wisconsin Card Sorting Manual: Revised and Expanded
Cited by (110)
Once-daily versus divided dosing regimens of clozapine: A cross-sectional study in Singapore
2023, Schizophrenia ResearchConsistency of adherence to antipsychotics between two bottles in patients with schizophrenia
2022, Schizophrenia ResearchAntipsychotic nonadherence measured by electronic adherence monitoring in stabilized chronic schizophrenia: Clinical implications
2021, Schizophrenia ResearchCitation Excerpt :Electronic adherence monitoring (EAM), such as the Medication Event Monitoring System (MEMS®), is considered the “gold standard” (Vrijens and Urquhart, 2014) among various adherence measurements. To date, there have been a number of such studies investigating adherence in patients with schizophrenia (Acosta et al., 2009; Byerly et al., 2005; Diaz et al., 2004; Misdrahi et al., 2018; Nakonezny and Byerly, 2006; Remington et al., 2007; Velligan et al., 2007; Yang et al., 2012). Our recent systematic review and meta-analysis of these studies revealed that oral antipsychotic adherence rates were approximately 70% (Yaegashi et al., 2020).
Engaging vulnerable populations in drug treatment court: Six month outcomes from a co-occurring disorder wraparound intervention
2021, International Journal of Law and Psychiatry