Long-term adherence to antipsychotic therapy is the cornerstone of contemporary management of psychosis, and patients who stop therapy have a markedly increased risk of exacerbation of disease.4 Patients with schizophrenia who take their medications as prescribed are much more likely to have positive outcomes, including a decreased likelihood of rehospitalization and better daily functioning and quality of life, compared with those who do not adhere to their prescribed medication regimens.5 In an analysis of Medicaid refill and medical claims data collected in California between 1999 and 2001 (N=4,325), risk of hospitalization among patients with schizophrenia correlated significantly with gaps in medication adherence (see Figure 1).6 Further, a review of the literature between 1995 and 2002 found that, for schizophrenia and for mental disorders generally, the most significant direct costs were related to hospitalization.7 This was true for initial episode costs as well as for subsequent relapses. The authors concluded that poor adherence with medication treatment “is likely to result in an increased frequency of relapse, more intense symptoms, and longer inpatient stays.”7
Almost every patient with schizophrenia is at risk for relapse at some point. In a study of individuals who had responded to treatment for their first psychotic episode, up to 82% had at least one psychotic relapse within 5 years, and 78% had a second relapse within that time.8 Patients who discontinued medication were almost five times more likely to relapse than patients who continued taking medication, whether it was the first or the second relapse.8 Therefore, in addition to other treatments that have been prescribed for patients with schizophrenia, such as cognitive behavioral therapy and social skills training, it is essential for these patients to take their medications as prescribed.
Unfortunately, like many patients with psychiatric disorders, those with schizophrenia generally do not adhere well to their prescribed medication regimens. While rates of medication nonadherence may reach as high as 40% for patients with chronic medical conditions in general,9 medication nonadherence rates in patients with schizophrenia can reach 50%.10 In a recent study of Medicaid beneficiaries with schizophrenia, 24% were found to be nonadherent, 16% were partially adherent, and 19% were “excess fillers—they received more days of medication than necessary for a given period.11 Medication nonadherence refers to any deviation from the prescribed regimen. While the more common pattern involves skipping doses or not taking medication for several days or even weeks, some patients may actually take extra doses of medications. Excess medication fills may result from overuse of antipsychotics to reduce symptoms or from confusion about the dosing regimen. Excess fills also may occur when a patient receives prescriptions for antipsychotic medications from several healthcare providers who are unaware that the person is seeing other prescribers. Overuse of medications increases the risk of adverse events.
When discussing medication nonadherence among patients with schizophrenia, it is important to understand that there is no such thing as a “typical” patient with schizophrenia. Individuals differ in the type and severity of their symptoms, and in their relative risk of relapse. Some patients with less intense symptoms can maintain meaningful relationships and hold jobs. Others with more severe illness may hope to live successfully in residential communities. Patients with severe schizophrenia, however, often must be hospitalized frequently or, in the worst cases, require lifelong inpatient care.
There is no specific degree of nonadherence that causes negative consequences in every patient. Missing a single dose can put some patients at risk; for others, medical and psychiatric issues may appear after a week or more of nonadherence. Of course, patients in any population, including those with schizophrenia, occasionally will miss a dose. However, when someone with schizophrenia misses several days at a time, a healthcare provider or educator should proactively intervene to stop the cycle before serious clinical consequences arise. This is especially true for patients who don't recognize that the medication is necessary to their well-being.
Reasons for Nonadherence
Patients with schizophrenia may not adhere to their prescribed medication regimens for several reasons, including the following.
Lack of insight
Many patients with schizophrenia have poor insight into their medical condition.10 They do not grasp the severity of their illness, and they may not believe that they need treatment. Some patients with schizophrenia don't accept that they have a mental illness.