A systematic review of studies reporting on neuropsychological and functional domains used for assessment of recovery from delirium in acute hospital patients

Objectives: Assessing for recovery in delirium is essential in guiding ongoing investigation and treatment. Yet, there is little scrutiny and no research or clinical consensus on how recovery should be measured. We reviewed studies which used tests of neuropsychological domains and functional ability to track recovery of delirium longitudinally in acute hospital settings.Methods/Design: We systematically searched databases (MEDLINE, PsycInfo, CINAHL, Embase, ClinicalTrials.gov, Cochrane Central Register of Controlled Trials), from inception to October 14th, 2022. Inclusion criteria were: adult acute hospital patients (≥18 years) diagnosed with delirium by a validated tool; 1+ repeat assessment using an assessment tool measuring domains of delirium/functional recovery ≤7 days from baseline. Two reviewers independently screened articles, performed data extraction, and assessed risk of bias. A narrative data synthesis was completed. Results: From 6,533 screened citations, we included 39 papers (reporting 32 studies), with 2,370 participants with delirium. Studies reported 21 tools with an average of four repeat assessments including baseline (range 2-10 assessments within ≤7 days), measuring 15 specific domains. General cognition, functional ability, arousal, attention and psychotic features were most commonly assessed for longitudinal change. Risk of bias was moderate to high for most studies.Conclusions: There was no standard approach for tracking change in specific domains of delirium. The methodological heterogeneity of studies was too high to draw firm conclusions on the effectiveness of assessment tools to measure delirium recovery. This highlights the need for standardised methods for assessing recovery from delirium.