BACKGROUND: Mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS) is the most prevalent type of surgically remediable epilepsy and highly associated with psychiatric comorbidities. This study aimed to evaluate Hospital anxiety and depression scale-anxiety subscale (HADS-A) and The State-Trait Anxiety Inventory - Trait subscale (STAI-T) accuracy for detection of anxiety disorders in patients with drug-resistant MTLE-HS.
METHODS: One hundred three consecutive patients with drug-resistant MTLE-HS were enrolled. Diagnosis was based on the anamnesis, neurological examination, video-electroencephalogram (VEEG) analyses, and magnetic resonance imaging (MRI). Psychiatric interviews were based on DSM-IV-TR criteria and ILAE Commission of Psychobiology classification as a gold standard; HADS-A and STAI-T were used as psychometric diagnostic tests, and receiver operating characteristic (ROC) curves were used to determine the optimal threshold scores.
RESULTS: The areas under the curve (AUCs) were higher than 0.7 (0.6-0.8) for both scales. The STAI-T cutoff point of ˃53 and the HADS-A cutoff point of ˃7 showed both around of 80% (44.4-97.7) sensitivity and 80% (66.9-86.9) and 60% (46.5-68.6) of specificity, respectively. In this sample the prevalence of anxiety disorders was 11.7% and both scales showed a high negative predictive value such as 96% (87.1-99.0) but low positive predictive value such as 30% (22.1-45.2) and 20% (15.0-27.2) respectively.
LIMITATIONS: The small number of cases in the diagnostic population; the results are only applied to drug resistant MTLE-HS; the psychiatric diagnosis were not based on a structured psychiatric interview; possible observer bias in 7 illiterate patients; the antidepressant treatment was not controlled.
CONCLUSIONS: In MTLE-HS, STAI-T and HADS-A had a similar and low positive predictive value and high negative predictive value. The implications for the HADS-A and STAI-T usefulness for anxiety disorders screening in patients with other epilepsies types deserve further investigations. If replicated in other populations, these findings may have important relevance for the presurgical screening of anxiety disorders in MTLE-HS patients who are candidates to epilepsy surgery.