Introduction: There are few studies on cognitive impairment in neuromyelitis optica (NMO). The purpose of this study is to assess the factors that may be related with the frequency and level of cognitive impairment in Turkish NMO patients. Methods: 22 patients with the diagnosis of NMO are evaluated retrospectively. Cognitive function was evaluated with Brief Repeatable Battery of Neuropsychological tests (BRB-N), Beck Depression Inventory (BDI) and Addenbrooke Cognitive Evaluation (ACE-R). The groups with and without cognitive impairment were compared according to age, sex, level of education, pathologic findings on cranial MRI, NMO Ig existence and EDSS score. The relation of the clinical, radiological and demographic values and patients’ depression level was evaluated. The specificity and sensitivity of ACE-R test on detecting cognitive impairment were assessed through ACE-R test results. Results: The mean age of the patients was 42.8±10.9.45.5% (n=10) of the patients had cognitive impairment and 50% (n=11) had depression. The group with cognitive impairment had significantly older age, lower educational status, higher EDSS and BDI scores (p
