Community-based epilepsy care in an onchocerciasis-endemic area: A 3-year cohort study in Mahenge, Tanzania.

Abstract

Objective: In onchocerciasis-endemic areas, limited access to antiseizure medications (ASMs) contributes to a high epilepsy burden. This study evaluated the impact of a community-based epilepsy care program in Mahenge, Tanzania, an onchocerciasis-endemic area with high epilepsy prevalence.

Methods: A baseline survey (2017-2018) identified persons with epilepsy (PWE) in four rural villages. Subsequently, PWE were invited to enroll in the epilepsy treatment program (2019-2022), where trained community health workers (CHWs) screened for epilepsy, promoted ivermectin intake to treat onchocerciasis, distributed ASMs, and monitored seizure frequency and ASM adherence monthly under supervision from the project clinician trained in epilepsy diagnosis and treatment. A concluding survey (2022) collected sociodemographic data and participants' status as alive, deceased, or lost to follow-up. Mixed-effects negative binomial regression analyzed risk factors for weekly seizure incidence rate.

Results: Of 206 participants, 77.7% reported bilateral tonic-clonic seizures, and 32.0% reported focal seizures. More than one third (38.5%) were suspected of having nodding syndrome. Weekly seizure frequency decreased significantly from a mean of 1.9 seizures (interquartile range [IQR] = 0-2) at enrollment to .4 seizures (IQR = 0-0) at the last follow-up (Wilcoxon test p < .0001), with significantly improved ASM adherence (57.5%-94.7%, McNemar test p < .0001). Factors associated with lower weekly seizure incidence included longer program participation, ASM adherence, carbamazepine use compared to phenobarbital, and ivermectin intake in 2022. ASM adverse events were associated with increased seizure frequency. The mortality rate was 32.7 deaths per 1000 person-years, with most deceased not fully adhering to ASM (88%) and having epilepsy-related causes of death (60%).

Significance: The community-based program using CHWs was associated with a significant reduction in seizure frequency and improved ASM adherence. In onchocerciasis-endemic areas, it should be investigated whether carbamazepine should be a preferred ASM in PWE. Ivermectin's impact on seizure frequency merits further investigation in onchocerciasis-endemic areas. Community-based epilepsy care is a promising strategy for scaling up epilepsy care in rural areas in Africa.