Risk factors for depression in patients with epilepsy

PURPOSE: Symptoms of depression are present in 40 to 60 percent of patients with epilepsy. Prior research indicated significant correlation between the incidence and frequency of focal seizures and clinical depression, especially in patients with temporal lobe epilepsy. Anticonvulsive drugs and psychosocial factors contribute to the occurrence of depression as well. The aim of the study was to determine the major depression risk factors in patients with epilepsy. METHODS: The research was conducted on 203 patients with epilepsy (117 females and 86 males), aged 18 to 50 years, with total time of illness ranging from 60 to 580 months. All subjects underwent the same research protocol, which was applied interictally. Interictal depression was diagnosed according to ICD-10 diagnostic criteria for affective and delusional disorders. The diagnosis was supported by Beck Depression Inventory (BDI), Hamilton Depression Rating Scale (HAM-D) and Montgomery-Asberg Depression Rating Scale (MADRS). Statistical analysis included chi2 test, Fisher's exact test and stepwise logical regression model analysis. RESULTS: In our study 100 patients with epilepsy out of 203 suffered from concurrent depression (49.2%); 76 of them had severe depression (37.4%) and 24 patients had mild depression (11.8%). Complex partial seizures and absence of secondary generalized tonic-clonic seizures were found to be the risk factors for depression. Treatment with clonazepam, frequent hospitalizations (drug-resistancy) and lack of occupational activity were revealed to be additional significant contributing factors. CONCLUSIONS: Depression in patients with epilepsy is a serious medical and social problem since it afflicts almost one half of all patients treated in epilepsy referral centers. It seems to be correlated with certain types of epileptic seizures, with high frequency of seizures, sub-optimal pharmacologic treatment and lack of occupational and social activity.