A house-to-house survey of epileptic seizures in an urban community of Rio de Janeiro, Brazil

OBJECTIVE: To carry out a prevalence study about epileptic seizures and epilepsy in an urban low-income population. METHOD: Prevalence study in a two-phase model: screening and diagnosis confirmation. It was applied a structured questionnaire in 982 people all effectively resident on March 1rst 2000 based on a population census previously carried out by the Nurse Faculty. One neurologist interviewed all the suspected cases. RESULTS: It was detected 176 suspected cases of epileptic seizures: 156 with non-epileptic events, and 20 with epileptic seizures. The lifetime point prevalence was of 16.3 cases per 1000 inhabitants, and of active epilepsy, 5.1 / 1000. If we consider false negative diagnosis from the screening procedures, the lifetime point-prevalence rates until 20.8/1000. CONCLUSION: The prevalence data of epilepsy shows less impressive than in other Latin-American studies and even some Brazilian, but similar to other Brazilian studies. This suggests geographical diversity and/or methodological differences among studies. Anyway, probably the epilepsy prevalence in Rio de Janeiro is not so high as that found in the Latin countries rural areas

Inferences from a community study about non-epileptic events

OBJECTIVE: To demonstrate the epidemiological importance of the different types of non-epileptic events (NEE) in a low-income urban community. METHOD: The patients suspected of having epilepsy, who were detected in the first phase (screening one) of this prevalence study, were interviewed by a neurologist in a non-structured neurological interview. These NEE were classified as physiological and psychogenic, subdivided by various types. The psychogenic NEE were classified according to the DSM-IV criteria. RESULTS: We compared the cases suspected of having epilepsy (n=176) with those not suspected (n=806) and discovered that those cases suspected of having epilepsy had a greater median age (<0.01) and female predominance (p<0.01). Among the cases suspected of having epilepsy there were different diagnosis: epileptic events without identifiable cause (n=20) or with identifiable causes (e.g., febrile convulsions and eclampsia). The most prevalent diagnosis for those suspected of having epilepsy was syncope (n=63; 35.8 percent). In terms of physiological events, the most frequent were: epileptic seizures, paroxysmal toxic phenomena (including alcoholism) and brain trauma, besides syncope; in terms of psychogenic events the most frequent were: dissociative and anxiety disorders. Regarding gender differences, paroxysmal toxic problems were significantly more prevalent in men (p= 0.02), and dissociative disorders (p=0.01) in women. CONCLUSION: This survey confirms the epidemiological importance of syncope in a populational sample with NEE. However, among the psychogenic disorders of this NEE sample, the most frequent were dissociative and anxiety phenomena. This finding contrasts with the literature based on samples from tertiary epileptic centers with video-EEG resources, which found somatoform disorders to be more prevalent than dissociative and anxiety phenomena