Course and prognosis of adult-onset epilepsy in Brazil: A cohort study.

BACKGROUND

Most of the epilepsy longitudinal studies have analyzed children. However, in endemic regions, such as Brazil, neurocysticercosis accounts for many adult-onset epilepsy cases. So, the main objective of this study was to identify the clinical predictors associated with drug-resistant adult-onset epilepsy in Brazil during a long-term follow-up.

METHODS

We followed 302 individuals with adult-onset epilepsy for 9.8 years in our University Hospital. Structured questionnaires about drug-resistant epilepsy were applied. The presence of drug-resistant epilepsy was the primary outcome. We used multilevel linear modeling in our data analysis.

RESULTS

Overall 47 (15.6%) individuals presented drug-resistant epilepsy and the etiology was structural in 70.2% of them, while infectious etiology was present in 8.5% of this group. Infectious etiology occurred in 25.9% (n = 66) of the patients from the nondrug-resistant group. Those with developmental delay were two times more likely to present seizures. Structural epilepsy etiology was associated with an increased chance of relapsing. Poor school performance and abnormal electroencephalogram were also associated with an increased chance of seizures.

CONCLUSION

The course of epilepsy was favorable in the majority of our patients, and drug-resistant epilepsy rates were similar to those found in other studies, although we evaluated older individuals with higher levels of infectious etiology. Also, we found that neurocysticercosis was associated with well-controlled epilepsy, while structural epilepsy was directly related to the occurrence of seizures. We also hypothesized that the smaller size of lesions found in neurocysticercosis could contribute to better treatment response.