Acute epilepsy exacerbations in patients switched between A-rated anti-epileptic drugs.

BACKGROUND: Concerns have been raised over the use of different manufacturers' versions of A-rated antiepileptic drug (AED) formulations in epilepsy patients. OBJECTIVE: To estimate the association between acute epilepsy exacerbations and switching between different A-rated AEDs. METHODS: A nested case-control study was conducted using pharmacy and medical claims data from January 1, 2005 through December 31, 2007. 18-65-year-olds who had an epilepsy diagnosis and received AED therapy during 2005 were eligible for study. Cases were defined as individuals with a documented exacerbation of epilepsy in the form of a 2006 or 2007 inpatient or emergency room claim for epilepsy. Controls were from the same population and matched on baseline epilepsy diagnosis and follow-up time since January 1, 2006. The exposure was a switch between A-rated AEDs in the 90 days prior to the matching date. Conditional logistic regression was used to estimate the odds of an epilepsy exacerbation after a switch controlling for important covariates. RESULTS: A total of 34 216 individuals were eligible for study, of whom 2949 cases were matched to 8847 controls. The unadjusted odds ratio (OR) between a switch and an epilepsy exacerbation was 1.51 (95% CI: 1.29-1.76). After adjusting for potential confounders, the odds ratio was 1.08 (95% CI: 0.91-1.29). Treatment with three or more AEDs or a change in outpatient diagnosis from baseline resulted in ORs of 2.96 (95% CI: 2.48-3.49) and 2.53 (95% CI: 2.28-2.82), respectively. CONCLUSIONS: After addressing potential confounders, no evidence that A-rated switching was associated with increased acute exacerbations of epilepsy was found. Study limitations include potentially incomplete identification of seizures, no information on indication for medication use, and limited information on duration and severity of disease. This study provides additional insight into the relationship between A-rated AED switching and acute exacerbations of epilepsy.

Prescribing COX-2s for patients new to cyclo-oxygenase inhibition therapy.

OBJECTIVES: To profile the pattern of cyclo-oxygenase 2 inhibitor (COX-2) use, including length of therapy, medical conditions treated, and gastrointestinal (GI) risk profile of users. STUDY DESIGN: Descriptive retrospective analysis of medical and prescription claims data from a large preferred provider organization in the Midwest. METHODS: During an index period of January through May 31, 2000, patients new to COX-2 therapy were evaluated 365 days before and after their first prescription. Among the inclusion criteria, patients had to have no previous use of COX-2 therapy, be at least 18 years of age, and be continuously eligible during the entire study period. RESULTS: Of the more than 300 000 members with at least 1 day of coverage in the index window, 1312 members met the inclusion criteria. The average age of COX-2 users was 49.5 years (SD = 11.4) and 60% were female. The number of days' supply of COX-2 agent obtained by members was highly skewed, with a mean of 116 days (SD = 119.5) and a median of 60 days. The medical conditions associated with COX-2 use included a variety of musculoskeletal conditions, the most common being low back pain (22%) and osteoarthritis (18%). Approximately 19% of members did not have a diagnosis associated with COX-2 use. Sixty-five percent of those new to COX-2 therapy did not have an indication of being at risk for GI events, and 68% had no indication for trying a lower-cost nonselective nonsteroidal anti-inflammatory drug (NSAID) prescription prior to beginning COX-2 therapy. Taken together, 45% did not have a GI risk factor or prior use of nonselective NSAID prescription therapy. CONCLUSIONS: These findings suggest that opportunities exist to encourage the cost-effective prescribing of COX-2 therapy. Possible methods include implementation of step therapy, academic detailing, and physician education programs, among others.