Risk Factors for Nodding Syndrome and Other Forms of Epilepsy in Northern Uganda: A Case-Control Study.

Nele Brusselaers,Marina Kugler,Nolbert Gumisiriza,Kevin Marsh,Amos Deogratius Mwaka,An Hotterbeekx,Rogers Sekibira,Rodney Ogwang,Albert Ningwa,Frank Mubiru,Catherine Abbo,Ronald Anguzu,Pamela Akun,Robert Colebunders,Richard Idro

doi:10.3390/pathogens10111451

Abstract

Epidemiological studies suggest a link between onchocerciasis and various forms of epilepsy, including nodding syndrome (NS). The aetiopathology of onchocerciasis associated epilepsy remains unknown. This case-control study investigated potential risk factors that may lead to NS and other forms of non-nodding epilepsy (OFE) in northern Uganda. We consecutively recruited 154 persons with NS (aged between 8 and 20 years), and age-frequency matched them with 154 with OFE and 154 healthy community controls. Participants’ socio-demography, medical, family, and migration histories were recorded. We tested participants for O. volvulus serum antibodies. The 154 controls were used for both OFE and NS separately to determine associations. We recruited 462 people with a median age of 15 years (IQR 14, 17); 260 (56.4%) were males. Independent risk factors associated with the development of NS were the presence of O. volvulus antibodies [aOR 8.79, 95% CI (4.15–18.65), p-value < 0.001] and preterm birth [aOR 2.54, 95% CI (1.02–6.33), p-value = 0.046]. Risk factors for developing OFE were the presence of O. volvulus antibodies [aOR 8.83, 95% CI (4.48–17.86), p-value < 0.001] and being born in the period before migration to IDP camps [aOR 4.28, 95% CI (1.20–15.15), p-value = 0.024]. In conclusion, O. volvulus seropositivity was a risk factor to develop NS and OFE; premature birth was a potential co-factor. Living in IDP camps was not a risk factor for developing NS or OFE.

Highlights

Nodding syndrome (NS) is a neurological disorder characterized by repeated headnodding
At some time in their life, 93.3% of all research participants resided in internally displaced people (IDP) camps
The median duration spent in IDP camps for persons with nodding syndrome (NS) and OFE was five years, and six years for controls (Table 2)

Summary

Introduction

Nodding syndrome (NS) is a neurological disorder characterized by repeated headnodding. The sanitation, housing, and general health conditions in IDP camps were poor, leading to several disease outbreaks [5]. The period of civil war and IDP camps coincided with the peak incidence of NS and other forms of epilepsy. This led to several hypotheses that directly or indirectly linked the etiopathology of NS to the war and IDP camp conditions [6,7,8,9,10]. Besides the epidemiological linkage between O. volvulus and NS, none of the hypotheses about the association between NS and IDP camp conditions has been confirmed so far [11,12]

Methods

Results

Discussion

Conclusion