ABSTRACT
PURPOSE: Although nonenzyme-inducing antiepileptic drugs (nEIAEDs) are accepted for the treatment of epilepsy, few studies have examined the costs, benefits, and cost-effectiveness of nEIAEDs in relation to the incidence of fracture among patients with epilepsy. In the present study, we performed cost-benefit and cost-effectiveness analyses comparing the influence of enzyme-inducing AEDs (EIAEDs) and nEIAEDs on the risk of fracture in this population. METHODS: A total of 4864 patients with epilepsy were classified into EIAED and nEIAED groups. Propensity score matching was applied to reduce the influence of selection bias. Clinical outcomes were measured in relation to AED fee, medical expenses associated with epilepsy and fracture, and the total number of fractures. Cost-benefit and cost-effectiveness analyses were performed for all patients. RESULTS: Patients in the unmatched EIAED cohort (nâ¯=â¯3686) were older and had more comorbidities. After matching, the cohorts exhibited similar features (nâ¯=â¯2432 each). Fracture risk was lower in the nEIAED group than in the EIAED group (HRâ¯=â¯0.70). The additional medical expense of nEIAEDs in fractures and epilepsy for 2â¯years per person was 107,731 New Taiwan dollars (NT$). The additional cost for nEIAEDs to reduce one event of fracture was $14,789,421 NT$. CONCLUSIONS: Patients with epilepsy using nEIAEDs had a lower risk of fracture than those using EIAEDs. However, the cost-benefit ratio and cost-effectiveness of such treatment were lower in the nEIAED group than in the EIAED group.
Subject(s)
Anticonvulsants/economics , Cost-Benefit Analysis/methods , Epilepsy/drug therapy , Epilepsy/economics , Fractures, Bone/chemically induced , Fractures, Bone/economics , Adult , Aged , Anticonvulsants/adverse effects , Anticonvulsants/therapeutic use , Cohort Studies , Female , Follow-Up Studies , Humans , Male , Middle Aged , Propensity Score , Retrospective Studies , Risk Factors , Young AdultABSTRACT
OBJECTIVE: Although classic anti-epileptic drugs have been associated with increased fracture risk, data are lacking on the outcomes of newer anti-epileptic drugs, such as gabapentin (GBP), levetiracetam, pregabalin, oxcarbazepine (OXC), and topiramate. This study was designed to determine fracture risks in the elderly associated with newly-developed anti-epileptic drugs. METHODS: A total of 2,169 patients (median age = 71.01 years, SD = 11.25 years) who experienced fractures between 2006 and 2013 were selected. For each case, age-, sex-, and comorbidity-matched controls were selected. The assessed clinical outcome was any fracture, and the use of anti-epileptic drugs was used as an exposure variable. RESULTS: There were no differences in age, sex, or comorbidities between patients and controls, but patients with fractures often lived in urban areas (odds ratio [OR] = 1.17; 95% confidence interval [CI] = 1.05-1.29) and had low income (OR = 1.14; 95% CI = 1.01-1.29) compared to controls. A significant increase in fractures was associated with OXC (OR = 3.31; 95% CI = 1.59-6.92), carbamazepine (CBZ; OR = 2.18; 95% CI = 1.31-3.61), and GBP (OR = 1.79; 95% CI = 1.01-3.18). Phenobarbital (OR = 1.97; 95%CI = 0.53-7.34), phenytoin (OR = 0.52; 95% CI = 0.23-1.16), levetiracetam (OR = 1.84; 95% CI = 0.55-6.16), valproic acid (OR = 1.01; 95% CI = 0.53-1.92), lamotrigine (OR = 1.44; 95% CI = 0.12-16.65), and topiramate (OR = 0.47; 95% CI = 0.10-2.31) were not associated with fracture risk. CONCLUSIONS: CBZ, GBP, and OXC users have a significantly higher risk of fracture. Most recently-developed anti-epileptic drugs are not associated with an increased risk of fracture in individuals aged ≥50 years.