Adherence Problems in Patients with Serious and Persistent Mental Illness

Objectives: Poor adherence to medication treatment canhave devastating consequences for patients with mental illness.The goal of this project was to develop recommendationsfor addressing adherence problems to improve patientoutcomes.

Methods: The editors identified important topics andquestions concerning medication adherence problems inserious mental illness that are not fully addressed in the literature.A survey was developed containing 39 questions(521 options) asking about defining nonadherence, extentof adherence problems in schizophrenia and bipolar disorder,risk factors for nonadherence, assessment methods,and interventions for specific types of adherence problems.The survey was completed by 41 (85%) of the 48 experts towhom it was sent. Results of the literature review and surveywere used to develop recommendations for assessingand improving adherence in patients with serious mentalillness.

Results: ASSESSING ADHERENCE: The experts endorsed percentageof medication not taken as the preferred method ofdefining adherence, with 80% or more of medication takenendorsed as an appropriate cut-off for adherence in bipolardisorder and schizophrenia. Although self- and physicianreport are the most common methods used to assess adherencein clinical settings, they are often inaccurate and mayunderestimate nonadherence. The experts recommend that,if possible, clinicians also use more objective measures (e.g.,pill counts, pharmacy records, and, when appropriate,serum levels such as are used for lithium). Use of a validatedself-report scale may help improve accuracy.

SCOPE OF THE PROBLEM: The majority of the experts believed the average patient with schizophrenia or bipolar disorder in their practices takes only 51%-70% of prescribed medication.

FACTORS ASSOCIATED WITH NONADHERENCE: The expertsendorsed poor insight and lack of illness awareness, distressassociated with specific side effects or a general fear of sideeffects, inadequate efficacy with persistent symptoms, andbelieving medications are no longer needed as the mostimportant factors leading to adherence problems in schizophreniaand bipolar disorder. The experts consideredweight gain a side effect that is very likely to lead to adherenceproblems in patients with schizophrenia and bipolardisorder; sedation was considered a more important contributorto adherence problems in bipolar disorder thanschizophrenia. The experts rated persistent positive or negativesymptoms in schizophrenia and persistent grandiosityand manic symptoms in bipolar disorder as the most importantsymptomatic contributors to adherence problems inthese illnesses.

INTERVENTIONS: It is important to identify the specific factorsthat may be contributing to a patient’s adherence problemsin order to customize interventions to target thoseproblems. Multiple problems may be involved, requiring acombination of interventions.

Conclusions: Adherence problems are complex and multidetermined.The experts recommended customized interventionsfocused on the underlying causes.