Missed doses of antiepileptic medications compromise benefits of therapy

Children with newly diagnosed epilepsy do not take their drug therapies regularly, and it could be for socioeconomic reasons.

A study published in the Journal of the American Medical Association found that almost 59% of children recently diagnosed with the disease and prescribed essential antiepileptic medications do not adhere to their therapies, in spite of the potential for short- and long-term toxic effects. Children of higher socioeconomic status were more likely to achieve better adherence; lack of financial resources may place children with epilepsy at risk.

Researchers at Cincinnati Children’s Hospital Medical Center enrolled a consecutive cohort of 124 children seen at their new-onset seizure clinic from April 2006 to March 2009. The children were aged 2 to 12 years, newly diagnosed by a pediatric epileptologist, beginning antiepileptic drug therapy, and free of developmental disorders or chronic illnesses needing daily medication.

Forty-eight percent of the cohort was diagnosed with idiopathic localization-related epilepsy; 15% with idiopathic unclassified epilepsy; 8% with cryptogenic localization-related epilepsy; 5% with cryptogenic generalized epilepsy; 5% with symptomatic localization-related epilepsy; and 0.8% with symptomatic generalized epilepsy. No children experienced prolonged seizures or status epilepticus during the study.

Medications were electronically monitored to check adherence. Caregivers removed pills or dispensed liquids from the bottles only at dosing times. Patients returned to the clinic 1 month after diagnosis and every 3 months after for follow-up. Frequency of seizures and adverse events were recorded at all visits, and medications were adjusted as necessary.

Adherence data for participants were assigned to 1 of 5 trajectories: severe early nonadherence, 13% (16 children stopped drug doses after 1 month); severe delayed nonadherence, 7% (8 children gradually stopped taking doses over time); moderate nonadherence, 13% (16 missed doses in any given week); mild nonadherence, 26% (32 averaged stable adherence about 85% of the time); and near-perfect adherence, 42% (52 incorporated regular drug therapy into family routine).

Seizure-related variables such as type, frequency, and adverse events did not affect adherence among the 5 groups. Only family socioeconomic status appeared to be a significant predictor of which children successfully adhered to their antiepileptic medication therapies.

Researchers note that caregivers’ attitudes and actions might contribute to missing drug doses, but they caution that even mild nonadherence may have serious clinical implications as to the therapeutic benefit of antiepileptic medications.

Modi AC, Rausch JR, Glauser TA. Patterns of nonadherence to antiepileptic drug therapy in children with newly diagnosed epilepsy. JAMA. 2011;305(16);1669-1676.