Self-reported adherence among people with epilepsy in Brazil

Nonadherence rates among people with epilepsy (PWE) are widely variable, ranging from 26% to 95.4%. We aimed to identify nonadherence in Brazil, its determinant factors, its impact on patients' management, and to compare it with other chronic nonparoxysmal diseases.

A multicenter observational case-control study was conducted between March 2015 and October 2016, and 153 subjects were included. Subjects' clinical-epidemiological data were surveyed with the Morisky-Green test (MGT), Brief Medication Questionnaire (BMQ), and the Liverpool adverse events profile (LAEP).

One hundred three PWE and 50 controls with other, nonparoxysmal chronic conditions were interviewed; both groups were matched according to age and socioeducational level. People with epilepsy were aged 36.4 ± 13.9 (range 18-67), 55% were women, mean age at epilepsy onset was 18.1 ± 15.5 years, 51.5% had pharmacoresistant epilepsy, and 48.5% were on monotherapy. 74.8% of patients and 70.0% controls were nonadherent to treatment according to MGT (p = 0.58); and barrier of recall (BMQ) was associated with nonadherence in 78% of PWE and 76% of controls (p = 0.84). Binary logistic regression analysis revealed LAEP (OR 1.05; 95%CI = 1.01-1.09; p = 0.03) and self-reported frequency of forgetfulness on the last three months (OR 19.13; 95%CI = 2.40-152.28; p < 0.01) as the main factors associated with nonadherence. Nonadherent subjects did not have more seizures and did not need emergency treatment more often than adherent ones.

Three of four PWE were not fully adherent to their treatment. Adherence assessment should be routine in all outpatient visits as well as interventions aimed to improving it. Adverse events are important predictors of adherence, and they should be considered when choosing the initial treatment of epilepsy.