Prevalence and risk factors for active convulsive epilepsy in rural northeast South Africa

Ryan G Wagner,Anthony K Ngugi,Rhian Twine,Christian Bottomley,Gathoni Kamuyu,F Xavier Gómez-Olivé,Myles D Connor,Mark A Collinson,Kathleen Kahn,Stephen Tollman,Charles R Newton

doi:10.1016/j.eplepsyres.2014.01.004

Abstract

Epilepsy is among the most common neurological disorders worldwide. However, there are few large, population-based studies of the prevalence and risk factors for epilepsy in southern Africa. From August 2008 to February 2009, as part of a multi-site study, we undertook a three-stage, population-based study, embedded within the Agincourt health and socio-demographic surveillance system, to estimate the prevalence and identify risk factors of active convulsive epilepsy (ACE) in a rural South African population. The crude prevalence of ACE, after adjusting for non-response and the sensitivity of the screening method, was 7.0/1,000 individuals (95% CI 6.4-7.6) with significant geographic heterogeneity across the study area. Being male (OR=2.3; 95% CI 1.6-3.2), family history of seizures (OR=4.0; 95% CI 2.0-8.1), a sibling with seizures (OR=7.0; 95% CI 1.6-31.7), problems after delivery (OR=5.9; 95% CI 1.2-24.6), and history of snoring (OR=6.5; 95% CI 4.5-9.5) were significantly associated with ACE. For children, their mother's exposure to some formal schooling was protective (OR=0.30; 95% CI 0.11-0.84) after controlling for age and sex. Human immunodeficiency virus was not found to be associated with ACE. ACE is less frequent in this part of rural South Africa than other parts of sub-Saharan Africa. Improving obstetric services could prevent epilepsy. The relationship between snoring and ACE requires further investigation, as does the relative contribution of genetic and environmental factors to examine the increased risk in those with a family history of epilepsy.

Highlights

Epilepsy is one of the most common neurological disorders in the world, affecting about 69 million people worldwide, with 90 percent living in low- and middle-income countries (LMICs) (Ngugi et al, 2010)
We identified patients with Active convulsive epilepsy (ACE) since convulsive epilepsies are associated with increased morbidity, mortality (Diop et al, 2005) and greater social stigma than non-convulsive epilepsies (World Health Organization, 2005)
A Odd Ratios adjusted for age and sex. b Indicates that an Odds ratio could not be calculated due to zero exposure in the control population. From this community-based research in rural northeast South Africa, we found the prevalence of epilepsy in a rigorous three-stage study to be lower than that reported elsewhere in sub-Saharan Africa (SSA)

Summary

Introduction

Epilepsy is one of the most common neurological disorders in the world, affecting about 69 million people worldwide, with 90 percent living in low- and middle-income countries (LMICs) (Ngugi et al, 2010). It contributes nearly one percent to the global burden of disease (Murray et al, 2012), and 20 percent of the global burden of epilepsy is in Africa (World Health Organization, 2004). Population-based surveys are frequently used to estimate prevalence, though not without limitations, including the absence of well-demarcated populations and vital statistics registries. This limitation, coupled with the lack of trained medical personnel available to make the diagnosis of epilepsy, makes estimating the burden of epilepsy in sub-Saharan Africa unusually challenging

Methods

Discussion

Conclusion