Objective: To estimate the pooled incidence of epilepsy from published studies and investigate sources of heterogeneity in the estimates.
Methods:We searched online databases for incidence studies and used meta-analytic methods to analyze the data.Results: Thirty-three articles met the entry criteria. The median incidence of epilepsy was 50.4/100,000/year (interquartile range [IQR] 33.6-75.6), while it was 45.0 (IQR 30.3-66.7) for high-income countries and 81.7 (IQR 28.0-239.5) for low-and middle-income countries. Population-based studies had higher incidence estimates than hospital-based studies (p ϭ 0.02) while retrospective study design was associated with lower estimates than prospective studies (p ϭ 0.04).
Conclusion:We provide data that could potentially be used to assess the burden and analyze the trends in incidence of epilepsy. Our results support the need for large population-based incidence studies of epilepsy. Neurology Epilepsy is one of the most prevalent noncommunicable neurologic conditions and an important cause of disability and mortality.1 It is estimated to affect almost 70 million people worldwide. 2 The prevalence of epilepsy in low-and middle-income countries (LMIC) is about twice that of high-income countries (HIC).2 Since mortality is high early in the course of epilepsy and spontaneous remission may occur, [3][4][5][6] prevalence data may significantly underestimate the burden of epilepsy. Thus, incidence of epilepsy, which is not diminished by disease-specific mortality, could be useful in enriching prevalence data in the assessment of the burden of epilepsy.While many prevalence studies have been reported, 2,7-9 there are only a few studies of incidence. Existing studies suggest a higher incidence of epilepsy in LMIC than in HIC, although it is not clear if this difference is real or due to methodologic differences.10 These estimates are diverse, limiting their utility in informing public health policy and resource allocation for prevention. Reasons for this variability are not clear.One published review of the incidence of epilepsy did not utilize meta-analytic methods. 11 It did not provide confidence intervals for the aggregate estimates, quantify heterogeneity in incidence rates, or identify the reasons for the observed variation.