Intentional and Unintentional Treatment Nonadherence in Patients With Systemic Lupus Erythematosus

Objective. Patients may be defined as nonadherent if they do not take their medications as prescribed by their physicians. Determinants of nonadherence may vary between and within patient groups. This study investigated the extent to which patients with systemic lupus erythematosus (SLE) show intentional and unintentional nonadherence, and the associations of nonadherence with psychological and medical parameters. Methods. The study included 106 patients who were receiving at least one immunosuppressive agent to control their SLE. Level of self-reported adherence and a measure of both intentional and unintentional nonadherence were obtained. Questionnaires were completed to assess associations between adherence and problems with cognitive functioning, beliefs about medicines, illness perceptions, emotional health, and disease characteristics. Results. The mean self-reported adherence rate for the total patient group was 86.7%. At least occasional intentional nonadherence was reported by 46.2% of patients and 58.5% of patients were at least occasionally unintentionally nonadherent. Problems with cognitive functioning, concerns about adverse effects of medication, and younger age were the strongest predictors of (non)adherence. Patients who were emotionally affected by their SLE were more likely to report low adherence, but this was not a significant predictor after accounting for other variables. Disease characteristics showed no relationship to measures of adherence. Conclusion. Although SLE patients reported high levels of adherence on average, they commonly reported intentional and unintentional nonadherence. Adherence was associated with both cognitions and emotions. Nonadherence may be reduced by targeting emotional and cognitive functioning and by fine tuning doctor-patient communication to address patients' individual concerns about their medications.