The role of cognitive functions in symptomatic remission and treatment resistant schizophrenia

THE ROLE OF COGNITIVE FUNCTIONS IN SYMPTOMATIC REMISSION AND TREATMENT RESISTANT SCHIZOPHRENIADr. Ahmet Yiğit AKTENERDokuz Eylul University Faculty of Medicine Deparment of PsychiatrySupervisor: Prof. Dr. Berna Binnur AKDEDEObjectives: Clinical concepts such as response, remission, recovery, relapse and treatment resistance are not well defined in schizophrenia. Symptomatic remission (SR) is the most well defined concept. Studies have shown many factors to be associated with SR but the association of cognitive functions is not well studied. Similarly, the relation of cognitive dysfuntion and treatment resistant schizophrenia (TRS) is poorly understood. Therefore the objectives of this study were the investigation of the association between cognitive functions and SR/TRS and to define the descriptive role of cognitive dysfunction in these clinical concepts.Methods: 122 patients diagnosed with schizophrenia were differentiated into patients in SR (N= 56) and patients not in SR (N= 66). The latter group was differentiated into patients with TRS (N= 29) and patients without TRS (N= 37). Neurocognitive functions were measured after clinical evaluation.Results: Patients in SR showed better overall performance in neurocognitive tests. Results were corrected according to years of education, a confounding factor. Although reduced, significant difference in cognitive functions amongst the groups persisted. Cognitive function comparison of the TRS/Non-TRS group revealed no difference.Conclusions: The findings of this study indicate that schizophrenia patients in SR have improved cognitive flexibility, abstraction, working memory, visual processing speed and semantic memory in comparison to patients not in SR. Better premorbid and perimorbid factors reveal the SR patients as a distinct group in the heterogenous disease we call schizophrenia.Key Words: Schizophrenia, cognitive functions, symptomatic remission, treatment resistant schizophrenia