Prevalence and associated risk factors of undiagnosed depression among people with epilepsy in a multiethnic society

BACKGROUND: Depression is the most frequent psychiatric comorbidity of epilepsy. However, clinicians often neglect to screen for depressive symptoms among patients with epilepsy and, therefore, fail to detect depression. Many studies have described the risks associated with depression in patients with epilepsy, but few studies have elaborated whether these risks are similar in those with undiagnosed depression, especially in a multiethnic community.

METHODS: In the present cross-sectional study conducted at a tertiary teaching hospital, we aimed to investigate the prevalence and associated risk factors of undiagnosed depression in patients with epilepsy. We recruited patients with epilepsy aged 18-65 years after excluding those with background illnesses that may have contributed to the depressive symptoms. In total, 129 participants were recruited. We collected their demographic and clinical details before interviewing them using two questionnaires-the Neurological Disorders Depression Inventory for Epilepsy and Beck's Depression Inventory-II. Subsequently, if a participant screened positive for depression, the diagnosis was confirmed using the Diagnostic and Statistical Manual of Mental Disorders questionnaire, and a psychiatric clinic referral was offered.

RESULTS: Among the 129 participants, 9.3 % had undiagnosed major depressive disorder, and there was a female preponderance (66.7 %). The risk factors for undiagnosed depression among patients with epilepsy included low socioeconomic background (p = 0.026), generalized epilepsy (p = 0.036), and temporal lobe epilepsy (p = 0.010). Other variables such as being underweight and unmarried were more common among patients diagnosed with depression than without but no statistically significant relationship was found.

CONCLUSION: The prevalence of undiagnosed depression among patients with epilepsy was higher than that in population-based studies conducted in Western countries. Although questionnaires to screen for depression are widely available, some clinicians rarely use them and, therefore, fail to identify patients who may benefit from psychosocial support and treatment that would improve their disease outcomes and quality of life. The present study indicated that clinicians should use screening questionnaires to identify undiagnosed depression in people with epilepsy.