Prevalence of psychiatric disorders in Thai patients with epilepsy

Many studies have shown that the prevalence of psychiatric disorders in patients with epilepsy (PWE) appears higher than that in general population. However, most epidemiological studies regarding psychiatric comorbidities among PWE were conducted in Western countries. This work aimed to determine the prevalence of psychiatric disorders in Thai PWE, including potential variables that could be associated with psychiatric disorders.

A cross-sectional study was conducted at Ramathibodi Hospital. A total of 170 patients (aged 18 years or older) diagnosed as having epilepsy by a neurologist were recruited at the outpatient neurology clinic. Demographic and clinical characteristics were collected. Participants were evaluated for any psychiatric disorders according to the Diagnostic and Statistical Manual of Mental Disorders, 4th edition, using a structured diagnostic interview. The prevalence of psychiatric disorders was determined. The associations between potential variables and the presence of psychiatric disorders in PWE were analyzed using chi-square or Fisher's exact tests, t-test, and logistic regression.

Among 170 patients, 43 (25.3%) fulfilled diagnostic criteria for one or more psychiatric disorders. The prevalence of depressive disorders was shown to be highest at 17.1%, followed by psychotic disorders (8.2%), bipolar disorder (7.1%), anxiety disorders (5.3%), and obsessive-compulsive disorder (OCD) (2.9%). Electroencephalogram (EEG) abnormalities in the temporal lobe was found to be a significant predictor of having psychiatric disorders in PWE (adjusted odds ratio (OR): 4.01, 95% confidence interval (CI): 1.47-10.92, P-value = 0.007).

The prevalence of psychiatric disorders among Thai PWE was higher than that in general population. Screening for psychiatric disorders in PWE is recommended, especially among those who have EEG abnormalities in the temporal lobe.