Alcohol as the cause of epileptic seizures
Evidence Summaries
The prevalence of epilepsy in alcohol-dependent patients of western industrialised countries may be at least triple that in the general population. During withdrawal from alcohol, usually 6–48 hours after the cessation of drinking, seizures may occur. Alcohol abuse is a major precipitant of status epilepticus (9–25% of cases).
A systematic review and meta-analysis 2 analyzing the association between alcohol consumption and epilepsy included 6 case-control studies. A strong and consistent association between alcohol consumption and epilepsy/unprovoked seizures was found with an overall relative risk (RR) of 2.19 (95% CI 1.83 to 2.63). There was a dose-response relationship between the amount of alcohol consumed daily and the probability of the onset of epilepsy. Individuals consuming an average of 4, 6, and 8 drinks daily had RRs of 1.81 (95% CI 1.59 to 2.07), 2.44 (95% CI 2.00 to 2.97), and 3.27 (95% CI 2.52 to 4.26), respectively, compared to nondrinkers. Most of the relevant studies found that a high percentage of alcohol users with epilepsy would qualify for the criteria of alcohol dependence. Data were inconclusive regarding a threshold for the effect of alcohol, but most studies suggest that the effect may only hold for heavy drinking (4 and more drinks daily).
Comment: The quality of evidence is downgraded study limitations (case-control studies) and upgraded by a clear dose-response gradient.