Neurocysticercosis and cognitive impairment among people with epilepsy in Taenia solium endemic regions of rural southern Tanzania: A hospital-based cross-sectional study in mental health clinics of selected sites in Tanzania

Background

Epilepsy poses a significant public health problem in many parts of the world. The majority of people with epilepsy (PWE) are from low-income and middle-income countries (LMICs). Taenia solium neurocysticercosis (NCC) is estimated to cause 30% of preventable epilepsy in PWE in areas of T. solium endemicity. This study was conducted to assess the prevalence of NCC in PWE, evaluate the presence of cognitive impairment in PWE, and assess potential contributing factors.

Methods

PWE were recruited within a mental health clinic-based cross-sectional study in rural Southern Tanzania. PWE underwent a detailed neurological examination, and a blood sample was collected for T. solium cysticercosis (CC) serology testing. Patients who were serologically positive for CC and those detected to have prominent neurological deficits apart from epilepsy were invited to receive a cerebral computed tomography (CT) examination.

Results

Out of the 223 people with epilepsy (PWE) recruited, 221 underwent clinical examination. Among these, 26 (11.8 %) had cognitive impairment, and 2 had additional neurological signs or symptoms. Twenty-five of the 223 PWE (11.2 %) tested positive for CC. A total of 36 participants underwent CT scans, with 18 testing positives for CC and 18 negatives. Of the 36 who had CT scans, 8 (22.2 %) were diagnosed with NCC; 7 were CC positive, and 1 was CC negative. Multivariate logistic regression confirmed that cognitive impairment in PWE was 8.62 times higher for Kongwa participants compared to Chunya, with a statistically significant association (95 % CI: 1.75–156; P<0.037). Additionally, having an education was associated with a 91 % reduction in the odds of NCC (OR=0.09) compared to no education, which was also statistically significant (95 % CI: 0.01 to 0.33; P<0.002).

Conclusion

Our study found a 22.2% prevalence of neurocysticercosis (NCC) among PWE. Cognitive impairment was present in 11.8% of PWE but was not significantly associated with NCC. Socioeconomic and educational factors may play a larger role in cognitive impairment among PWE.