Cognitive Function in Patients Undergoing Chemotherapy: a Systematic Review

Abstract

Introduction: Studies suggest that, in addition to the systemic effects, chemotherapy can lead to cognitive alterations in patients. These changes have had increasing attention due to the repercussion that these effects cause in patients who survive a cancer treatment. Objective: To study the domains of cognitive function impaired in patients who underwent chemotherapy, by means of a systematic review of the evaluation methods used to identify the presence of these alterations and their possible mechanisms of occurrence. Method: A systematic review was conducted from a bibliographic survey of articles from the last 10 years, in the Lilacs, Medline and Pubmed database. the key words were randomly combined in Portuguese: “quimioterapia”, “cognicao”, “neurotoxicidade”, “antineoplasicos”, “cancer”, and in English "chemobrain", "Neurocognitive function", "chemofog." Results: The cognitive function presented itself impaired after chemotherapy was carried out. A large array of evaluation methods of the cognitive function was found, highlighting the lack of standardization. The possible mechanisms for which chemotheraphy provokes impairment are related to the capacity of crossing the blood-brain barrier; DNA damage, regulation of cytokines, neural repair, genetic alteration of neurotransmitters, and changes in the levels of estrogen and testosterone hormones. Conclusion: The following cognitive domains: verbal memory, working memory, executive function, attention, concentration, language and motor speed are the most affected in patients undergoing chemotherapy.