Psychosis in epilepsy patients and other chronic medically ill patients and the role of cerebral pathology in the onset of psychosis: A clinical epidemiological study

SummaryBackgroundIn a 3-year epidemiological survey (N = 2623) prevalence of psychosis in epilepsy patients as compared with other chronic medically ill patients is assessed.AimTo explore the role of cerebral pathology as compared to the role of chronic burden of disease in the onset of psychosis.MethodOne thousand seven hundred fifty two patients with chronic medical disorders admitted to an Academic Hospital and 901 patients with epilepsy admitted to a tertiary care epilepsy clinic were assessed by CIDI, MINI and clinical psychiatric interview in a two stage screening survey. Medical files were searched for MRI scans about cerebral pathology. Poisson regression analysis was performed to estimate the relative risk for psychosis in both groups.ResultsIn total, 52 patients with prevalent psychosis were found: 49 (5.4%) in the epilepsy clinic and 3 (0.17%) in the Academic Hospital. Age range (18–88), mean age (42) and gender distribution (equal) were similar in both samples. RR is 8.37 (2.74, 25.52). In 16 of the 49 epilepsy patients, cerebral pathology existed with mainly temporal and frontal localisation and of childhood-onset vascular or infectious origin.ConclusionsThis finding suggests that in the onset of psychosis in epilepsy patients, the role of cerebral pathology, especially localized left temporal and frontal, is of strong etiological importance. The following epilepsy endophenotypes should be explored as factors in vulnerability for psychosis as well: frequent and severe epileptic activity; and psychotic reactions to certain AEDs, such as Topiramate and Lamotrigine. Burden of disease does not seem to play an important role.