Anxiety disorders, subsyndromic depressive episodes, and major depressive episodes: do they differ on their impact on the quality of life of patients with epilepsy?

AIMS OF THE STUDY: To compare the impact of anxiety disorders, major depressive episodes (MDEs), and subsyndromic depressive episodes (SSDEs) on the quality of life of patients with epilepsy (PWEs), and to identify the variables predictive of poor quality of life.
METHODS: A psychiatric diagnosis according to DSM-IV-TR criteria was established in 188 consecutive PWEs with the MINI International Neuropsychiatric Interview. Patients also completed the Beck Depression Inventory-II (BDI-II), the Centers for Epidemiologic Studies-Depression (CES-D), and the Quality of Life in Epilepsy-89 (QOLIE-89). A diagnosis of SSDE was made in any patient with total scores of the BDI-II >12 or CES-D >16 in the absence of any DSM-IV diagnosis of mood disorder according to the MINI.
RESULTS: Patients with SSDEs (n = 26) had a worse quality of life than asymptomatic patients (n = 103). This finding was also observed among patients with MDEs only (n = 10), anxiety disorders only (n = 21), or mixed MDEs/anxiety disorders (n = 28). Furthermore, having mixed SSDEs/anxiety disorders yielded a worse quality of life than having only SSDEs. Independent predictors of poor quality of life included having a psychiatric disorder and persistent epileptic seizures in the last 6 months.
CONCLUSIONS: Although isolated mood and anxiety disorders, including SSDE, have a comparable negative impact on the quality of life of PWEs; the comorbid occurrence of mood and anxiety disorders yields a worse impact. In addition, seizure freedom in the previous 6 months predicts a better quality of life.