title: The cognitive effects of opioids in cancer: a systematic review.
abstract: OBJECTIVE
  In order to better understand the effects of opioids on the cognitive function in cancer pain patients, a literature search was performed in PubMed, EMBASE, PsycInfo, CINAHL and Lilacs databases. Ten controlled trials were selected and classified according to the study design, the level of evidence, and opioid regimen.
  
  
  RESULTS
  Six studies reported association between poor cognitive performance (reaction time, attention, balance, and memory) and opioid use.
  
  
  CONCLUSIONS
  These cognitive deficits were captured with neuropsychological tests; however, their clinical relevance is still uncertain.
authors.affiliation: Multidisciplinary Pain Centre, Dept. 7612, Rigshospitalet, Blegdamsvej 9, 2100, Copenhagen, Denmark. geana@rh.regionh.dk
authors.forename: Geana Paula
authors.initials: GP
authors.lastname: Kurita
authors.forename: Lena
authors.initials: L
authors.lastname: Lundorff
authors.forename: Cibele Andrucioli de Mattos
authors.initials: CA
authors.lastname: Pimenta
authors.forename: Per
authors.initials: P
authors.lastname: Sjøgren