Medication Compliance

Medication Compliance

Introduction

Compliance, or the degree to which patients’ behaviors coincide with the recommendations of health care providers, is an important component in the understanding of patient outcomes, particularly in light of a growing regimen of efficacious and expensive medical treatments. There is an evident gap between the efficacy of regimens tested in tightly controlled clinical trials and their effectiveness when applied to “real world” patient experiences. One explanation for this “efficacy-effectiveness gap”, when treatment regimens move from efficacy trials into everyday practice, is the apparent decline in patient compliance. Other terms closely related to compliance include “adherence”, “fidelity”, and “maintenance”.

Compliance is difficult to quantify for several reasons. Completely attributing the difference between an expected and observed treatment effect to problems with medication com-pliance may be overly simplistic. Several other factors such as differences in population, degree of comorbidity with other psy-chiatric or medical diagnoses, and severity of illness may all ad-versely affect the potential benefit to the patient. Poor or partial compliance with treatment may have a variable effect on treat-ment outcomes depending on the pharmacokinetic profile of the medication in question. For example, occasional missed doses of very long half-life medications will alter serum drug levels to a lesser extent than in short half-life compounds. Therefore, the issue of partial compliance with treatment regimens may become more critical depending on the specific regimen.

A Theoretical Construct for Compliance: The Health Beliefs Model

The health beliefs of individuals play a major role in their deci-sion-making processes regarding participation in recommended treatment. A framework that may be useful in understanding the complex nature of compliance with medical regimens is the health beliefs model (HBM). Derived from social psychological theories of Kurt Lewin, the HBM is grounded in the phenom-enological orientation of perception driving action (Rosenstock, 1974). While this model was originally designed to study the utilization of screening tests for detection of asymptomatic diseases, it has been adapted to the areas of medication compli-ance among psychiatric patients (Kelly et al. 1987).

Five components of the HBM apply directly to issues of patient compliance. Figure 88.1 depicts the relationship between these components and ultimate compliance with treatment.

Susceptibility: patients must see themselves as vulnerable to a serious illness.

·    Severity: patients must realize that he/she has an illness with health consequences that will continue without medical attention.

·   Perceived benefits: patients must recognize that an effective treatment exists for their condition. Benefits from psycho-tropic medication treatment may include the understanding that treatment ameliorates mental problems or helps avoid rehospitalization.

·   Barriers: common barriers to pharmacologic interventions in-volve access to medication, adequate psychiatric follow-up, and adverse effects from the medication.

·   Cues to action: lastly, patients must experience an internal or external motivation or “cue” to engage in the specified action that may benefit them.

Cues that may trigger a patient to participate in their medica-tion regimen typically relate to a return of symptoms attributed to their mental illness such as anxious, depressive, or psychotic states.

Another Conceptual Model of Compliance

Another approach to understanding compliance behavior involves the categorization of problems with compliance along the three domains of psychological problems, planning problems, and medical problems. These three domains have been used to develop a compliance checklist as seen in Table 88.1 (Corrigan et al., 1990, Cramer 1991). Psychological problems include issues such as nonacceptance of diagnosis or treatment, negative emotional reactions or negative thoughts, and social criticism from family or friends. Problems with planning consist of forgetting to take medications, disruption of usual schedules, and issues with availability of medication. Medical problems that affect compliance include adverse reactions, exacerbation of illness that leads to incapacity to administer or tolerate medications, or perceptions that medications may lack efficacy in a given individual. Both HBM and the compliance checklist provide useful starting points to begin the analysis of problems with compliance in specific patients or patient populations.

Interventions to Enhance Compliance

General strategies to enhance compliance take many forms and can be tailored to the specific needs identified in individual pa-tients. Most approaches to enhance compliance involve the intro-duction of techniques to improve outpatients’ self-administration of oral medication therapies. Cramer (1991) identifies several strategies to approach problems with compliance (Table 88.2).

The action of monitoring compliance itself may improve adherence to proposed medical regimens, just as frequent weight monitoring may promote weight loss even without a specific diet regimen. Some data indicate that compliance rates improve sig-nificantly when outpatients with psychiatric disorders are given continuous feedback on their medication dosing (Cramer and Rosenheck, 1999).

Compliance-enhancement interventions that have been studied include individual, group and family formats and involve diverse theoretical orientations. Unfortunately, many of the studies that investigate compliance therapies do not also assess the distal impact on treatment outcomes leaving the clinician unable to evaluate whether marginal improvements in compliance would in fact lead to cost-effective improvement in treatment outcomes.

One intervention referred to as compliance therapy utilizes a specific approach to individual or group psychotherapy with cognitive therapy and motivational interviewing techniques (Goldstein, 1992; Hayward et al, 1995). Therapists attempt to help the patients form a cognitive link between discontinuation of medication treatment and relapse of symptoms. Using the patient’s frame of reference, therapists seek to instill a sense of cognitive dissonance between discontinuation of medication and achievement of the patient’s own goals. Problem-solving techniques are also employed to identify internal and external cues that may compromise future medication compliance.

Other psychosocial interventions to increase compliance in patients with schizophrenia have also been demonstrated to be effective. Kelly and Scott (1990) found that strategies aimed at ed-ucation of patients’ families about compliance and those directed at patients themselves both improved compliance. No significant difference between the two interventions could be demonstrated. It is important to note that, given the multiple factors associated with clinical course, not all improvement in treatment outcomes in schizophrenia is directly attributable to improved medication compliance. Psychosocial interventions that lack a specific fo-cus on treatment compliance may nonetheless have salutatory effects on patient outcomes, regardless of changes in compliance behavior. Zhang and colleagues (1994) found that family therapy without a specific focus on compliance produced improvement in relapse rates in schizophrenic patients independent of changes in medication compliance.

Another approach to increasing compliance involves the change in route of administration of medication from oral preparationsthatmustbetakenatleastoncedailytodepotinjections, such as haloperidol decanoate and fluphenazine decanoate, that are typically administered every 2 to 4 weeks. The advantages to depot preparations include supervised administration of the medication by health care providers, decreased variability in serum concentrations of the active medication, and no significant difference in adverse effects as compared with similar oral agents. Disadvantages include the limited number of medications available in depot form, the difficulty of scheduling potentially more frequent clinic visits for injections, and the increased cost

in clinic staffs’ time with administration of the treatments. At the time of this publication, no atypical antipsychotic agents were available in depot form. Therefore, a comparison of compliance with conventional depot agents and atypical oral agents may be limited in utility. Few studies of depot antipsychotic preparations address the issues of long-term compliance and differences in health outcomes when compared with oral agents (Adams and Eisenbruch, 2002; Quraishi and David, 2002). However, some evidence suggests that depot antipsychotic agents do confer a marginal improvement in reducing relapse rates (Glazer and Kane, 1992).