Cognitive impairment and posttraumatic stress in breast cancer patients during the first year after diagnosis

Cancer patients frequently report symptoms of cognitive impairment and posttraumatic stress. Until recently, it was assumed that cognitive deteriorations in cancer patients are attributable to neurotoxic effects of chemotherapy. However, new research indicates that cognitive impairment cannot be caused by cancer treatment alone – most likely also cancer-related posttraumatic stress affects cognition. Elucidating the causes of cognitive dysfunction and posttraumatic stress in cancer patients is crucial for prevention and effective psychological intervention. This cumulative dissertation summarizes two publications of the prospective, longitudinal and controlled COGNICARES-study, which were published in peer-reviewed international journals with current impact factors that rank among the top 80% in the Journal Citation Report. COGNICARES is the first large study that applied an extensive neuropsychological test battery and a validated clinical interview at three assessment times, to measure cognitive functioning and posttraumatic stress in women with mamma carcinoma and in a control group. Prior to the start of any cancer treatment, limited cognitive impairment was found in cancer patients, which was mediated by posttraumatic stress. Only few patients were diagnosed with a full-blown acute or posttraumatic stress disorder (ASD, PTSD) but shortly after the cancer diagnosis, more than 80% of patients experienced symptoms of PTSD, which did not completely resolve during the first year after cancer diagnosis in the majority of patients. Implications of the findings are discussed in the context of the recently published Diagnostic and Statistical Manual of Mental Diseases-V (DSM-V).