Pediatric Patients With Undetectable Anticonvulsant Blood Levels: Comparison With Compliant Patients

Abstract

Undetectable anticonvulsant blood levels indicate sustained noncompliance (several consecutive doses missed). We compared 91 consecutive outpatients with epilepsy and undetectable anticonvulsant blood levels to 100 patients seen during the same time period, verified as compliant by acceptable serum levels. We hypothesized that pay status, application for Supplemental Security Income, patient age, history of missed appointments, and functional status would differ between compliant and noncompliant patients. We were surprised to find large differences between clinic and insurance patients and between Caucasian and non-Caucasian patients. The 100 compliant patients included 44 Caucasian and 56 non-Caucasian patients, whereas only 9 of 91 noncompliant patients were Caucasian, and only 9 had insurance, compared to 32 compliant patients. Applications for Supplemental Security Income and history of missed appointments were significantly associated with noncompliance, but patient age, seizure type, and seizure control were not. Uninsured Caucasians were more often compliant than non-Caucasians were. Many noncompliant patients had mild epilepsy, which was reportedly doing well. Race and pay status were closely correlated. Several noncompliant females became pregnant, whereas no compliant patients did. Compliant patients were much more likely to be accompanied by a parent or caretaker on clinic visits than noncompliant patients. Noncompliant patients had at least one acceptable subsequent serum level, although 2 patients with intractable epilepsy had undetectable serum levels on three or more occasions. Noncompliance may respond to discussion and advice. We reviewed 124 episodes of undetectable drug levels in the 91 noncompliant patients. Eighteen of these resulted in hospitalization, but in 25 cases, we were told that there had been no seizures since the preceding visit. Many noncompliant patients have infrequent seizures, even if they take little or no medication. Socioeconomic status influences health, life expectancy, and educational success, but it has been claimed to be irrelevant to compliance and adherence issues in epilepsy. Our data and the experience of other centers with childhood diabetes suggest that socioeconomic, racial, and family factors influence compliance or adherence to treatment for many chronic conditions. Educational efforts and support for parents at the start of anticonvulsant treatment may improve compliance. Uninsured patients missed more appointments and were much more likely to be noncompliant than insured patients. Attention to the special problems of Medicaid and minority children is needed.

Adherence to antiepileptic drugs among children attending a tertiary health unit in a low resource setting

“…The main reasons for missing drugs were similar to what has been reported by Faris et al and Snodgrass et al respectively [16, 27]. The cost of drugs limits caregivers from purchasing them in case they are not availed at the clinic due to other priorities such as rent and food which usually override purchasing of medication thus leading to non adherence.…”

“…This may explain the differences in therapeutic drug levels from our study compared to other studies. [25–27]. …”

Medication compliance among children

“…Age, socioeconomic status, race, and family factors can also influence compliance to treatment, especially in children with asthma, epilepsy, and diabetes. [8,9] One survey among parents of children with asthma indicated that parental concerns about controller medication were associated with poor medication compliance. Parents may stop the daily inhaler for the child when their child feels better, thinking that will prevent the adverse reactions of medication.…”

Identification and Prevention of Antiepileptic Drug Noncompliance: The Collaborative Use of State-Supplied Pharmaceutical Data

“…This variation in the pharmacokinetics captured by TDM has been used to justify higher dosages in such patients [21, 22, 26, 27]. With respect to a noncompliant patient, this dose escalation is a potentially harmful practice as failure to verify and distinguish a noncompliant patient versus a patient with variable pharmacokinetics can lead to the overtreatment of noncompliant patients [8]. In addition to this complex scenario, it is important to realize that the variable of pharmacodynamics, or the actual patient responsiveness, is not captured by TDM and therefore provides another counter argument against its clinical usefulness [8, 28].…”

“…With respect to a noncompliant patient, this dose escalation is a potentially harmful practice as failure to verify and distinguish a noncompliant patient versus a patient with variable pharmacokinetics can lead to the overtreatment of noncompliant patients [8]. In addition to this complex scenario, it is important to realize that the variable of pharmacodynamics, or the actual patient responsiveness, is not captured by TDM and therefore provides another counter argument against its clinical usefulness [8, 28]. In other words, some patients may remain clinically stable despite subtherapeutic serum levels of the AED simply because of variations in pharmacodynamics among patients.…”