Depression in persons with epilepsy: A comparative study of different tools in Indian population

Depression is an important co-morbidity in persons with epilepsy (PWE) and its timely identification is essential. The aim of the study was to assess and compare the psychometric properties of potentially suitable screening tools of depression in PWE in a tertiary care setting in India.

After ethical clearance, 449 PWE above 18 years of age, on anti-seizure drugs (ASDs), attending epilepsy clinic in neurology outpatient department (OPD) of All India Institute of Medical Sciences, New Delhi, India, were recruited and evaluated for depression using different tools namely: Neurological Disorders Depression Inventory for Epilepsy (NDDI-E), Patient Health Questionnaire (PHQ-9) and Hamilton Depression Rating Scale (HAM-D). Mini International Neuropsychiatric Interview (MINI: Module A, version 6.0.0) was used as reference standard. The association if any of depression with PWE variables was also determined.

A variable percentage of PWE were positive for depression- 40.1% with MINI, 40.5% with NDDI-E, 44.3% with HAM-D and 45.4% with PHQ-9. Suicidal ideation was present in 4.5% of PWE. The sensitivity and specificity of scales using MINI as a reference standard were found to be maximal at scores ≥5, ≥8 and >11 for PHQ-9, HAM-D, and NDDI-E, respectively. The ROC analysis revealed a statistically significant difference among NDDI-E and PHQ-9 (p = 0.0268). Polytherapy in PWE had significant association with risk of depression (p < 0.01) and female PWE had 1.5 times the odds of depression as compared with males (95% CI, 1.02-2.2).

All the tools used in this study were found to be appropriate for use in PWE if cut-off points are validated. The choice of tool can be based on the clinical setting.