Loading...
Nonadherence or partial adherence to antipsychotic medications occurs in 50% to 75% of patients with schizophrenia during the first several years of treatment and substantially increases the risk for relapse. A gap in medication adherence (even 1–10 days) is associated with a doubling of the risk for hospitalization. In this prospective study, 49 patients enrolled within 2 years after a psychotic episode (schizophrenia spectrum, >90%) were stabilized on risperidone (average baseline dose, 4.2 mg/day) and then followed weekly for 18 months.
Using multiple ascertainment methods at weekly visits, investigators rated patients' nonadherence as severe (missing ≥50% of prescribed doses for ≥4 consecutive weeks during follow-up), moderate (missing ≥50% for ≥2 but <4 consecutive weeks), mild (missing 25%–50% for ≥2 weeks), or adherent.
Some degree of nonadherence was common (mild, 33%; moderate, 16%; severe, 19%). Overall, 27% of patients experienced psychotic symptoms sufficient to meet exacerbation or relapse criteria (hazard ratios for return of psychotic symptoms: mild nonadherence, 5.8; moderate nonadherence, 28.5). Nonadherence periods typically began 6 months after outpatient stabilization; the mean time from the beginning of nonadherence to relapse was 72 days.
Subotnik KL et al. Risperidone nonadherence and return of positive symptoms in the early course of schizophrenia. Am J Psychiatry 2011 Jan 4; [e-pub ahead of print]. (http://dx.doi.org/10.1176/appi.ajp.2010.09010087)
Comment
Even brief interruptions of risperidone are strongly associated with increased risk for exacerbation or relapse, suggesting little leeway for nonadherence to oral antipsychotics. Even before becoming less adherent, some of these patients might have been at elevated risk for relapse because they had less treatment response or more adverse medication effects than adherent patients. Studies to better delineate patient characteristics predictive of nonadherence are needed. Clinicians should be mindful that the risk for nonadherence is greatest about 6 months after medication stabilization, with symptom exacerbation emerging 2 months later. Screening for risk factors and instituting measures to increase adherence in those at greatest risk could help avert relapse.