Abstracts

Rationale: Caffeine is a central nervous stimulant which acts by blocking of A1 and A2 adenosine receptors. Animal studies indicate that caffeine may induce seizures, and there are anecdotal reports of patients with seizures after ingestion of drinks with high caffeine content. We wished to study the role of caffeine as a seizure precipitant in a clinical settingMethods: Patients hospitalized for epileptic seizures (n=174) were interviewed concerning their caffeine consumption during 24 h prior to admission and their habitual caffeine intake. Caffeine consumption during 24 h was also recorded at a later telephone interview on a seizure free day (n=154, median 15 weeks after admission). Beverages containing caffeine were recorded as units defined as cups of coffee and tea and small bottles of caffeine containing soft drinks/energy drinks. Categorized data were analyzed using the Wilcoxons signed-ranks test. Results: Epilepsy was diagnosed in 123 patients. Brain abnormalities and/or localized EEG findings indicated seizures with focal onset in 101 patients. No difference was found between the 24 h intake of caffeine prior to the seizure and the reported habitual consumption (p=0.37), or the consumption on a seizure free day (p=0.13). There was also no significant difference between the reported habitual intake and the intake on a seizure free day (p=0.23). Nevertheless eight patients had increased their caffeine intake by at least 5 units (mean 6,8) on the day of the seizure. Conclusions: The average intake of caffeine was not increased during the last 24 h prior to a seizure in this study. Caffeine does not appear to be a common seizure precipitant, but may in some patients be a contributing factor.