New use of anticonvulsant medications among children enrolled in the Tennessee Medicaid Program
W. O. Cooper, C. F. Federspiel, M. R. Griffin and G. B. Hickson
Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, Tenn, USA. william.cooper@mcmail.vanderbilt.edu
OBJECTIVE: To describe the new use of anticonvulsant medications among
children enrolled in the Tennessee Medicaid program. DESIGN: A
retrospective cohort study. PATIENTS: New users of anticonvulsant
medications in 1992 were identified from the 206,098 children (aged 0-18
years) enrolled continuously for 12 months in the Aid to Families With
Dependent Children program or foster care program of Tennessee Medicaid.
MAIN OUTCOME MEASURES: New users were categorized according to the
diagnosis codes of health care encounters occurring 90 days before to 90
days after the first anticonvulsant prescription was filled as having
diagnoses consistent with (1) epilepsy or convulsions, (2) neonatal
seizures, (3) central nervous system disease, (4) no epilepsy diagnoses but
diagnoses for which anticonvulsants might appropriately be used (jaundice,
headaches, or psychiatric disorders), or (5) no diagnoses for which an
anticonvulsant might appropriately be used. The children in each group were
described according to sociodemographic variables, with logistic regression
used to analyze variations in the subsequent filling of anticonvulsant
prescriptions. RESULTS: Of 647 children continuously enrolled in the
Tennessee Medicaid program who were new anticonvulsant users in 1992, 58%
had at least 1 health care encounter coded as epilepsy or convulsions, 2%
had a diagnosis of neonatal seizures, 8% had central nervous system
diagnoses, 16% had specific nonepilepsy diagnoses (jaundice, headache, or
psychiatric diagnoses), and 16% had no diagnoses for which anticonvulsants
might appropriately be prescribed. For children with epilepsy diagnoses,
white race (P = .002) and undergoing tests (P < .001) were independent
predictors of a child filling 6 or more prescriptions in the year following
the first prescription CONCLUSIONS: A large proportion of new users of
anticonvulsants among children enrolled in the Tennessee Medicaid program
received these medications for indications other than epilepsy. For
children with epilepsy diagnoses, there was considerable variation in the
subsequent filling of prescriptions. Further analysis of these variations
in practice will allow for the development of policies that will maximize
benefit for children who need anticonvulsant therapy, while diminishing
unnecessary exposure to potentially toxic drugs for children who do not.
