Accuracy of Psychiatrists’ Assessment of Medication Adherence in an Outpatient Setting

Background: Many patients have uncontrolled psychiatric symptoms because they are not taking their medication as prescribed. Psychiatrists may have difficulty accurately assessing medication adherence, which is important because it helps guide them in how they prescribe. If nonadherence is the cause of uncontrolled symptoms, then strategies to improve adherence are advised. However, if nonadherence is not the cause, then the usual course of action would be to intensify or modify the medication regimen. Knowing whether nonadherence is a factor at the time of an appointment could help guide clinical decision making in real-time. Methods: A cohort of established patients in an outpatient mental health treatment clinic at a large health network was studied from November 2018 to August 2019. Blood drug levels of several oral antipsychotic medications were obtained and placed in the following three categories: below, within, or above the therapeutic range of published cutoff points. Treating physicians answered Likert-scale questions regarding their assessment of patient adherence. Subsequently, blood drug levels were compared to the psychiatrists’ assessment of adherence using a Kappa coefficient. Results: Sixty-four patients being prescribed antipsychotic medications were analyzed. A total of 87.5% of treating psychiatrists thought their patients were always adherent or adherent greater than 50% of the time. However, based on blood levels, 14% of the 42 patients at target FDA dosing for their medication and diagnosis were below the therapeutic range. The Kappa coefficient was used to find the level of agreement between the treating psychiatrist’s perception of patient adherence and the blood drug level. It was determined to be 0.14 which is consistent with no agreement between the two measurements. Conclusions: Treating psychiatrists inaccurately estimated oral antipsychotic medication adherence based on clinical impression alone. Making an objective measure of adherence available at the time of an appointment could help psychiatrists recognize nonadherence in real-time and inform prescribing decisions.