Dataset Information

Epilepsy in the Sanaga-Mbam valley, an onchocerciasis-endemic region in Cameroon: electroclinical and neuropsychological findings.

ABSTRACT:

Objective

Epilepsy is highly prevalent in onchocerciasis-endemic African regions. Various types of epilepsy have been described in such regions based essentially on clinical characteristics.

Methods

We conducted a clinical, neurophysiological and neuropsychological study of epilepsy in the onchocerciasis-endemic region of Ntui, Sanaga-Mbam area, Cameroon.

Results

One hundred and eighty-seven persons with presumed epilepsy were recruited in an epilepsy clinic in Ntui. Epilepsy was clinically confirmed in 144 (79%) subjects, 69 (46.0%) of them met the onchocerciasis-associated epilepsy (OAE) criteria, and 51 of 106 tested (48.1%) presented Ov16 antibodies. Electroencephalograms (EEG) were recorded in 91 participants, of which 36 (33%) were considered abnormal and 27 of 36 (75%) revealed bifrontotemporal spike and slow waves. Concerning the neuropsychological evaluation, 29% showed severe global cognitive impairment, 28% severe episodic memory impairment, and 66% severe frontal cognitive impairment. Half of the persons with epilepsy (PWE) suffered from a mental disorder.

Significance

In PWE in the Sanaga-Mbam area in Cameroon, we observed EEG patterns similar to those described among persons with OAE, including nodding syndrome in other onchocerciasis-endemic areas. Most PWE presented with severe cognitive impairment. We hypothesize that onchocerciasis may induce neurocognitive disorders and epilepsy via a mechanism that involves mainly the frontal and temporal regions of the brain.

SUBMITTER: Morin A

PROVIDER: S-EPMC8408605 | biostudies-literature | 2021 Sep

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Epilepsy in the Sanaga-Mbam valley, an onchocerciasis-endemic region in Cameroon: electroclinical and neuropsychological findings.

Morin Alexandre A Guillaume Maxime M Ngarka Leonard L Tatah Godwin Y GY Siewe Fodjo Joseph Nelson JN Wyart Guillaume G Nokam Ghislain G Tchoumi Thierry T Nkinin Mary Bello MB Njamnshi Wepnyu Y WY Chokote Eric-Samuel ES Boussinesq Michel M Colebunders Robert R Chesnais Cédric B CB Gargala Gilles G Parain Dominique D Njamnshi Alfred K AK

Epilepsia open 20210803 3

<h4>Objective</h4>Epilepsy is highly prevalent in onchocerciasis-endemic African regions. Various types of epilepsy have been described in such regions based essentially on clinical characteristics.<h4>Methods</h4>We conducted a clinical, neurophysiological and neuropsychological study of epilepsy in the onchocerciasis-endemic region of Ntui, Sanaga-Mbam area, Cameroon.<h4>Results</h4>One hundred and eighty-seven persons with presumed epilepsy were recruited in an epilepsy clinic in Ntui. Epilep ...[more]

PMID: 35138694

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Project description:BackgroundA high epilepsy prevalence has been reported in several onchocerciasis-endemic villages along the Mbam and Sanaga river valleys in Cameroon, including Bilomo and Kelleng. We sought to determine the prevalence of epilepsy in these two villages following more than 13 years of community-directed treatment with ivermectin (CDTI).MethodsDoor-to-door surveys were performed on the entire resident population in the villages in August 2017 and January 2018. Epilepsy was diagnosed using a 2-step approach: administration of a standardized 5-item questionnaire followed by confirmation by a neurologist. Previously published diagnostic criteria for onchocerciasis-associated epilepsy (OAE) were used. Ov16 serology was done for children aged 7-10 years to assess onchocerciasis transmission. Findings were compared with previous data from these two villages.ResultsA total of 1525 individuals (1321 in Bilomo and 204 in Kelleng) in 233 households were surveyed in both villages. The crude prevalence of epilepsy was 4.6% in Bilomo (2017) and 7.8% in Kelleng (2018), including 12 (15.6% of cases) persons with epilepsy (PWE) with nodding seizures. The age and sex-standardized prevalence in Kelleng decreased from 13.5% in 2004 to 9.3% in 2018 (P < 0.001). The median age of PWE shifted from 17 (IQR: 12-22) years to 24 (IQR: 20-30) years in Bilomo (P < 0.001); and slightly from 24 (IQR: 14-34) years to 28 (IQR: 21.25-36.75) years in Kelleng (P = 0.112). Furthermore, 47.6% of all tested children between 7 and 10 years had Ov16 antibodies.ConclusionsThere is a decrease in epilepsy prevalence after 13 years and more of CDTI in both villages. The age-shift observed in PWE suggests that ivermectin may prevent OAE in younger residents. Ov16 seropositivity in children indicates ongoing onchocerciasis transmission possibly due to suboptimal control measures. Our findings support the existence of OAE in Cameroon and highlight the need to strengthen onchocerciasis elimination programs.

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Dataset Information

Epilepsy in the Sanaga-Mbam valley, an onchocerciasis-endemic region in Cameroon: electroclinical and neuropsychological findings.

Objective

Methods

Results

Significance

Publications

Epilepsy in the Sanaga-Mbam valley, an onchocerciasis-endemic region in Cameroon: electroclinical and neuropsychological findings.

Similar Datasets

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