Indications of newer and older anti-epileptic drug use: findings from a southern Italian general practice setting from 2005-2011.

AIMS

The aim of the study was to analyze the prescribing pattern of both newer and older AEDs.

METHODS

A population of almost 150 000 individuals registered with 123 general practitioners was included in this study. Patients who received at least one AED prescription over 2005-2011 were identified. The 1 year prevalence and cumulative incidence of AED use, by drug class and individual drug, were calculated over the study period. Potential predictors of starting therapy with newer AEDs were also investigated.

RESULTS

The prevalence of use per 1000 inhabitants of older AEDs increased from 10.7 (95% CI10.1, 11.2) in 2005 to 13.0 (95% CI12.4, 13.6) in 2011, while the incidence remained stable. Newer AED incidence decreased from 9.4 (95% CI 8.9, 9.9) in 2005 to 7.0 (95% CI 6.6, 7.5) in 2011, with a peak of 15.5 (95% CI 14.8, 16.1) in 2006. Phenobarbital and valproic acid were the most commonly prescribed AEDs as starting therapy for epilepsy. Gabapentin and pregabalin accounted for most new pain-related prescriptions, while valproic acid and lamotrigine were increasingly used for mood disorders. Female gender (OR 1.36, 95% CI 1.20, 1.53), age ranging between 45-54 years (OR 1.39, 95% CI 1.16, 1.66) and pain as an indication (OR 16.7, 95% CI, 13.1, 21.2) were associated with newer AEDs starting therapy.

CONCLUSIONS

Older AEDs were mainly used for epileptic and mood disorders, while newer drugs were preferred for neuropathic pain. Gender, age, indication of use and year of starting therapy influenced the choice of AED type. The decrease of newer AED use during 2007 is probably related to the restricted reimbursement criteria for gabapentin and pregabalin.