Publication
Title
The temporal relationship between onchocerciasis and epilepsy : a population-based cohort study
Author
Abstract
Background Many studies have suggested that onchocerciasis might be associated with epilepsy. Therefore, we did a cohort study to assess the incidence of epilepsy relative to Onchocerca volvulus skin microfilarial density (MFD) measured during childhood and to assess the possibility of a temporal relationship. Methods During onchocerciasis surveys undertaken in 25 villages in Cameroon during 1991-93, we measured MFD in individuals aged 5 years or older. In 2017, we revisited seven of these villages. With a standardised five-item questionnaire, we collected information on the occurrence of epilepsy in 856 individuals who were aged 5-10 years in 1991-93, and had MFD determined during the original surveys. We did multivariable analyses to assess the overall incidence and incidence ratios taking into account age, sex, individual MFD in 1991-93, and onchocerciasis endemicity level in the village. Findings In 2017, we obtained data on the history of epilepsy for 85% (729 of 856) of individuals. Among these individuals, we classified 60 as being suspected cases of epilepsy. The overall incidence of epilepsy was 350 per 100 000 person-years (95% CI 270-450). The adjusted incidence ratio for developing epilepsy was 7.07 (95% CI 0.98-51.26; p=0.0530) in individuals with initial MFD of one to five microfilariae per skin snip (mf per snip), 11.26 (2.73-46.43) in individuals with six to 20 mf per snip, 12.90 (4.40-37.83) in individuals with 21-50 mf per snip, 20.00 (3.71-108.00) in individuals with 51-100 mf per snip, 22.58 (3.21-158.56) in individuals with 101-200 mf per snip, and 28.50 (95% CI 3.84-211.27; 13=0.0010) in individuals with more than 200 mf per snip, compared with that of individuals without detectable densities of skin microfilariae. Interpretation Individual O volvulus MFD in childhood was associated with the risk of either seizures or epilepsy in an onchocerciasis focus in Cameroon. This temporal relationship suggests a potential causal link between onchocerciasis and epilepsy. Copyright (C) 2018 Elsevier Ltd. All rights reserved.
Language
English
Source (journal)
The lancet infectious diseases. - London
Publication
London : 2018
ISSN
1473-3099
DOI
10.1016/S1473-3099(18)30425-0
Volume/pages
18 :11 (2018) , p. 1278-1286
ISI
000448325300037
Pubmed ID
30268645
Full text (Publisher's DOI)
Full text (publisher's version - intranet only)
UAntwerpen
Faculty/Department
Research group
Publication type
Subject
Affiliation
Publications with a UAntwerp address
External links
Web of Science
Record
Identifier
Creation 10.12.2018
Last edited 09.10.2023
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