Secular Trends in the Incidence, Prevalence, and Medications for Epilepsy from 2007 to 2015 in Taiwan: A Nationwide Population-Based Study

Abstract

Background: Patients with epilepsy have a higher mortality rate than the general population. Up-to-date estimates of epilepsy incidence, prevalence, and medication use are critical to assist policymaking. Methods: Using the National Taiwan Insurance Research Database, the standardized incidence and prevalence of epilepsy were estimated in each calendar year from 2007 to 2015. We used the incident cases of epilepsy to analyze the change in prescribing patterns from 2007 to 2015. Joinpoint regression was used to estimate secular trends. Results: From 2007 to 2015, the age- and sex-standardized incidence decreased from 0.72 (95% confidence interval [CI] 0.70–0.73) to 0.54 (95% CI 0.53–0.55) per 1,000 person-years, giving an annual percentage change (APC) of −2.73 ( p < 0.05). Among patients younger than 20 years, the incidence did not change significantly. The age- and sex-standardized prevalence decreased from 6.94 (95% CI 6.90–6.98) to 6.86 (95% CI, 6.82–6.89) per 1,000 people, giving an APC of −0.31 ( p < 0.05). However, the prevalence increased in the 35- to 49- and 50- to 64-year age-groups. The most common first-line anticonvulsant was phenytoin in 2007 and valproate in 2015. The use of levetiracetam, clobazam, and valproate increased during the study period, with APCs of 25.48% (95% CI 19.97–31.24), 6.41 (3.09–9.85), and 2.83 (1.51–4.16), respectively. The use of carbamazepine, phenytoin, and topiramate decreased; the APCs were −23.86% (95% CI −25.25 to −22.44), −6.61 (−8.40 to −4.79), and −4.29% (−7.87 to −0.57), respectively. Conclusions: The overall prevalence and incidence of epilepsy decreased slightly from 2007 to 2015. The prescribed first-line anticonvulsant also changed over time.