Risk Factors and Etiologies of Epilepsy in Urban and Rural Rwanda

Risk factors and etiologies of epilepsy in the Rwandan population will be determined using two phases. The initial phase (Task 1) includes the recruitment of the study population using two separate surveys. The first survey (Task 1.1.) will be conducted in the general population by a door-to-door (D2D) approach. During D2D visits in 10 selected urban and rural villages throughout the country, one rural and one urban per province, persons of the households with permanent residence will be interviewed by enumerators to screen for epilepsy. In case of a positive screening, they will be assessed by a team of Rwandan and Belgian neurologists to confirm the epilepsy diagnosis. During a second survey (Task 1.2.), PwE will be matched with control persons defined as persons who screened negative during the Task 1.1 survey.

The second phase of our study (Task 2) consists of the assessment of potential risk factors associated with epilepsy using the matched case-control group (Task 2.1.), and the identification of underlying etiology in PwE according to the International League Against Epilepsy (ILAE) etiology guidelines (Task 2.2.).

Task 2.1. Both cases and controls will complete a structured questionnaire on a wide range of potential risk factors present before the onset of the epilepsy, administered by research assistants. In addition, blood samples from both PwE and controls will be collected as to measure the exposure to parasitic infections and HIV, and the presence of sickle cell disease, among others. Exposure will be measured by detection of IgG antibodies to parasitic antigens including Taenia solium, Toxoplasma gondii and Plasmodium falciparum as well as HIV in plasma samples of the participants.

Task 2.2. Further, in order to classify PwE according to the ILAE etiology guidelines, we will use the detailed medical and epilepsy history including in-depth narrative of seizure description and frequency, clinical examination and narrative of epilepsy treatment assessed by the team of neurologists subsequent to the confirmation of the epilepsy diagnosis. In addition, all PwE will undergo EEG recording using a mobile device. Furthermore, PwE will undergo CT- or MRI-imaging unless previous imaging studies have been performed and are accessible for re-evaluation.

Inclusion criteria

• Inhabitants of the selected villages who screen positive on the Limoges epilepsy screening questionnaire during the D2D visits and have a confirmed epilepsy diagnosis assessed by a team of Rwandan and Belgian neurologists, are included as PwE. Epilepsy will be defined as unprovoked recurrent seizures occurring more than 24h apart, including active and lifetime epilepsy.
• Persons with a negative screening during the D2D visits who match with a PwE for age and gender and have an absence of epilepsy confirmed during a clinical assessment by a team of Rwandan and Belgian neurologists, are included as control persons.

Exclusion criteria

• Inhabitants of the selected villages who are unwilling to complete a verbal witnessed informed consent during D2D visits. For patients ≤18 years of age, verbal consent will be obtained from their parents/caregivers.
• PwE and selected control persons who are unwilling to sign a written informed consent upon referral for neurological assessment.
• PwE and control persons not meeting the inclusion criteria.