ObjectivesWe aimed to determine age-specific rates of delirium and associated factors in acute medicine, and the impact of delirium on mortality and re-admission on long-term follow-up.DesignObservational study. Consecutive patients over two 8-week periods (2010, 2012) were screened for delirium on admission, using the confusion assessment method (CAM), and reviewed daily thereafter. Delirium diagnosis was made using the Diagnostic and Statistical Manual Fourth Edition (DSM IV) criteria. For patients aged ≥65 years, potentially important covariables identified in previous studies were collected with follow-up for death and re-admission until January 2014.Participants503 consecutive patients (age median=72, range 16–99 years, 236 (48%) male).SettingAcute general medicine.ResultsDelirium occurred in 101/503 (20%) (71 on admission, 30 during admission, 17 both), with risk increasing from 3% (6/195) at <65 years to 14% (10/74) for 65–74 years and 36% (85/234) at ≥75 years (p<0.0001). Among 308 patients aged >65 years, after adjustment for age, delirium was associated with previous falls (OR=2.47, 95% CI 1.45 to 4.22, p=0.001), prior dementia (2.08, 1.10 to 3.93, p=0.024), dependency (2.58, 1.48 to 4.48, p=0.001), low cognitive score (5.00, 2.50 to 9.99, p<0.0001), dehydration (3.53, 1.91 to 6.53, p<0.0001), severe illness (1.98, 1.17 to 3.38, p=0.011), pressure sore risk (5.56, 2.60 to 11.88, p<0.0001) and infection (4.88, 2.85 to 8.36, p<0.0001). Patients with delirium were more likely to fall (OR=4.55, 1.47 to 14.05, p=0.008), be incontinent of urine (3.76, 2.15 to 6.58, p<0.0001) or faeces (3.49, 1.81–6.73, p=0.0002) and be catheterised (5.08, 2.44 to 10.54, p<0.0001); and delirium was associated with stay >7 days (2.82, 1.68 to 4.75, p<0.0001), death (4.56, 1.71 to 12.17, p=0.003) and an increase in dependency among survivors (2.56, 1.37 to 4.76, p=0.003) with excess mortality still evident at 2-year follow-up. Patients with delirium had fewer re-admissions within 30-days (OR=0.32, 95% CI 0.09 to 1.1, p=0.07) and in total (median, IQR total re-admissions=0, 0–1 vs 1, 0–2, p=0.01).ConclusionsDelirium affected a fifth of acute medical admissions and a third of those aged ≥75 years, and was associated with increased mortality, institutionalisation and dependency, but not with increased risk of re-admission on follow-up.

The stronger relationship between impairment on the MoCA with hypertensive arteriopathy, independent of age, indicates a greater sensitivity for vascular-origin cognitive impairment. Use of MoCA should improve sensitivity for cognitive impairment and treatment effects in future studies.

Background We determined the impact of a system-wide multicomponent intervention to improve recognition and documentation of cognitive frailty syndromes on hospital administrative coding for delirium. Methods A multicomponent intervention including introduction of structured patient assessment including cognitive/delirium screen, regular audit/feedback and educational seminars was undertaken (2012-17). Sensitivity and specificity of administrative International Classification of Diseases, 10th revision (ICD-10) delirium codes for the gold standard of prospectively clinically diagnosed delirium were calculated in consecutive patients admitted to acute medicine over five 8-week cycles (2010-18). Results Among 1,281 consecutive unselected admissions to acute medicine overall (mean / standard deviation age = 70.0/19.2 years; n=615 (48.0%) male), 320 had clinical delirium diagnosis (n=220 delirium only; n=100 delirium on dementia). Sensitivity of delirium coding increased from 12.8% (95% confidence interval (CI) 5.6-26.7) in 2010 to 60.2% (95% CI 50.1-69.7; p trend <0.0001) in 2018 while specificity remained at >99% throughout. Conclusion A multicomponent intervention increased sensitivity of hospital administrative diagnostic coding for delirium almost six-fold without increasing the false positive diagnosis rate.

Background: reliable delirium risk stratification will aid recognition, anticipation and prevention and will facilitate targeting of resources in clinical practice as well as identification of at-risk patients for research. Delirium risk scores have been derived for acute medicine, but none has been prospectively validated in external cohorts. We therefore aimed to determine the reliability of externally derived risk scores in a consecutive cohort of older acute medicine patients.Methods: consecutive patients aged ≥65 over two 8-week periods (2010, 2012) were screened prospectively for delirium using the Confusion Assessment Method (CAM), and delirium was diagnosed using the DSM IV criteria. The reliability of existing delirium risk scores derived in acute medicine cohorts and simplified for use in routine clinical practice (USA, n = 2; Spain, n = 1; Indonesia, n = 1) was determined by the area under the receiver operating characteristic curve (AUC). Delirium was defined as prevalent (on admission), incident (occurring during admission) and any (prevalent + incident) delirium.Results: among 308 consecutive patients aged ≥65 (mean age/SD = 81/8 years, 164 (54%) female), existing delirium risk scores had AUCs for delirium similar to those reported in their original internal validations ranging from 0.69 to 0.76 for any delirium and 0.73 to 0.83 for incident delirium. All scores performed better than chance but no one score was clearly superior.Conclusions: externally derived delirium risk scores performed well in our independent acute medicine population with reliability unaffected by simplification and might therefore facilitate targeting of multicomponent interventions in routine clinical practice.