title: Self-reports are not related to objective assessments of cognitive function and sedation in patients with cancer pain admitted to a palliative care unit.
abstract: Cancer patients often report complaints of cognitive impairment and sedation. It is not well known if subjective complaints reflect objective assessments of cognitive function (CF) and sedation. We obtained self-reports of sedation and CF from 29 patients admitted to a palliative care unit and receiving morphine treatment. Sedation was reported on a verbal rating scale (VRS) and CF was reported using the EORTC QLQ-C30 health-related quality-of-life questionnaire CF scale. The self-reports were compared with objective assessments of sedation and CF by applying the Observer's Assessment of Alertness/Sedation (OAA/S) scale and Mini Mental State Examination (MMS), respectively. The assessments were repeated for seven patients who were readmitted to the palliative care unit. The patient self-reports of memory, concentration and sedation were dichotomized into noncomplainers and complainers. The percentages of complainers were 54%, 46% and 37% for memory, concentration and sedation, respectively. Patients who complained from difficulties with concentration or memory did not score differently from noncomplainers on objective assessments of CF (MMS score), but had a significantly higher level of fatigue. Patients complaining from sedation did not score differently from noncomplainers on objective assessments of sedation (OAA/S score). We observed no significant correlations between EORTC QLQ-C30 CF scale scores and MMS scores, or between VRS sedation scores and OAA/S scores. The study demonstrates a lack of relationship between patient self-reports and objective methods for assessing sedation and cognitive failure. This finding illustrates the importance of differentiating between observations and patient self-reports. The results also question the validity of patient self-reports for measurements of cognitive failure and sedation.
authors.affiliation: Department of Anesthesia and Medical Imaging, Norwegian University of Science and Technology, Trondheim. pal.klepstad@medisin.ntnu.no
authors.forename: Pål
authors.initials: P
authors.lastname: Klepstad
authors.forename: Priscilla
authors.initials: P
authors.lastname: Hilton
authors.forename: Jorunn
authors.initials: J
authors.lastname: Moen
authors.forename: Bjørn
authors.initials: B
authors.lastname: Fougner
authors.forename: Petter C
authors.initials: PC
authors.lastname: Borchgrevink
authors.forename: Stein
authors.initials: S
authors.lastname: Kaasa
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000701:Analgesics, Opioid / Q000627:therapeutic use*; D003071:Cognition / Q000187:drug effects*; D003243:Consciousness / Q000187:drug effects*; D005221:Fatigue; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009020:Morphine / Q000627:therapeutic use*; D009369:Neoplasms / Q000150:complications; D010146:Pain / Q000188:drug therapy* / Q000209:etiology; D010166:Palliative Care; D011446:Prospective Studies
chemical_list: D000701:Analgesics, Opioid; D009020:Morphine