소아간질 환자의 복약 순응도 분석

Abstract

ABSTRACT

Background: Antiepileptic drug (AED) is the mainstay treatment of epilepsy, a brain disease characterized by recurrent unprovoked seizures. AEDs are designed to intervene in these processes to decrease excitability, thereby stopping and preventing seizure activity. Although AED may not cure the condition, it can decrease the frequency and severity of seizure. Non-adherence to AED therapy is reported to result in increased seizure recurrence and seizure-related hospitalizations in adults. Despite the importance of AED treatment, studies on medication adherence in pediatric epilepsy are insufficient.Objectives: We aimed to evaluate persistence and adherence to AED treatment in pediatric epilepsy, to assess influence of medication taking behavior on clinical outcome and to identify factors affecting them.Methods: Medical and prescription records of children (1 ≤ age ≤ 18 years) diagnosed with epilepsy and first prescribed of AED monotherapy from 1 Jan 2008 to 30 Jun 2011 at Seoul National University Hospital (SNUH) were retrospectively reviewed. Three years of follow up was allowed. Treatment persistence, treatment adherence and clinical outcome incidence were evaluated. Patients with treatment gap of more than 60 days were considered non-persistent. Overall treatment non-persistence, having treatment gap or treatment discontinuation for any reason including clinical intentions, and patient treatment non-persistence, excluding those who discontinued AEDs from clinical reasons, were separately assessed. Clinical outcome was defined as emergency department (ED) visit or hospitalization due to seizure-related reasons from second to third year after treatment initiation. Treatment adherence was evaluated in patients with at least 3 outpatient AED prescriptions. Adherence was calculated with medication possession ratio (MPR), proportion of days covered by prescriptions over defined treatment period. Patients with MPR of at least 80% were considered to be adherent to AED therapy. Results: A total of 1172 patients met the inclusion criteria. Around 73.7%, 60.3%, and 43.5% of patients were overall treatment persistent with AED therapy over 1, 2 and 3 years, respectively. 14.5%, 20.4% and 31.4% of patients discontinued AED therapy by physician’s decision, thereby cumulative patients’ non-persistence rates were 11.8%, 19.3%, 25.1% over 1, 2, and 3 years, respectively. Toddlers (1 year of age), and patients who were prescribed new generation AED as initial treatment regimen showed significantly low overall 2 year treatment persistence (P<0.05). New AED prescription was the only significant factor affecting two-year patient treatment persistence (Hazard ratio (HR), 0.657, 95% confidence interval (CI) 0.54-0.81 compared with old AED). During the first year of AED treatment, 82.8 % were adherent to AED therapy and around 5% of patients showed very low adherence (MPR below 60%). Patient who started treatment as adolescents, 12-18 years (Odds ratio(OR) 2.74, 95% CI 1.03-7.29 vs. 1 year age group), patients living rural area (OR 1.79, 95% CI 1.13-2.81 vs. city area) showed significantly higher non-adherence. The incidence of clinical outcome over two years after one year of treatment was 7.34% (n=86). Patient treatment non-persistence was correlated with clinical outcome (P<0.05). Conclusions: This study showed patient treatment non-persistence of 19.3% over 2 years and 1 year adherence rate of 82.3% to AEDs in pediatric epilepsy. Both overall and patient treatment non-persistence were correlated with generation of AED of initiation therapy. Patient treatment non-persistence was associated with seizure-related clinical outcome. Further research is warranted to investigate the reasons for non-persistence and non-adherence in pediatric population.