The Need to Develop Innovative Interventions to Improve Treatment Adherence in Co-Occurring Severe Mental Illness and Substance Use Disorders

Abstract

Treatment nonadherence is a significant public health problem that spans medical and psychiatric populations, adding billions of dollars to healthcare costs [1]. Patients with chronic and severe mental illness (SMI), such as schizophrenia and bipolar disorder, as well as those with substance use disorders (SUDs) tend to exhibit high rates of nonadherence (e.g., 50% or greater) to their medication and psychosocial treatments [2-7]. Not surprisingly, then, nonadherence rates tend to be highest in SMI patients who also abuse drugs or alcohol compared with noncomorbid patients [8]. Nonadherence in co-occurring SMI and SUDs produces a host of negative consequences, including increased rates of relapse, hospitalization, suicide, and functional impairment [5,9-11]. Abrupt withdrawal from psychotropic medications for SMI can lead to a quick return of symptoms that is not just attributable to the original illness, but also due to potential rebound effects associated with withdrawal from medications [12,13]. Furthermore, premature treatment drop out averages 50% within the first few weeks of SUD treatment [4-6], which prevents early intervention that can alter illness trajectories and provide needed course corrections prior the development of clinical crises. Nonadherence also contributes to the so-called “efficacy-effectiveness gap” [14]. We spend large amounts of money and resources developing efficacious mental health treatments, but these interventions will have little public health impact unless patients view them as acceptable and adhere to them.